32-samss-021

Previous Issue: 6 September 2008 Next Planned Update: 18 January 2015 of 41 Primary contact: Anizi, Salamah Salem on 966-3-8760203

Copyright©Saudi Aramco 2010. All rights reserved.

Materials System Specification

32-SAMSS-021 18 January 2010

Manufacture of Industrial Boilers

Heat Transfer Equipment Standards Committee Members Anizi, Salamah Salem, Chairman Bagawi, Jamil Jarallah, Vice Chairman Anezi, Mohammed Ali Dossary, Musfir Abdullah Fernandez, Gabriel Thomas Gahtani, Moraya Saif Guthami, Mohammed Mohsen Hamam, Ibrahim Hassan Harbi, Abdullah Mohammed Saeed Mansour, Khalid Mohammad Naffaa, Mahmoud Youniss Rumaih, Abdullah Mohammad

Saudi Aramco DeskTop Standards Table of Contents 1 Scope............................................................. 2 2 Conflicts and Deviations................................. 2 3 References..................................................... 2 4 Definitions and Abbreviations......................... 5 5 Responsibilities............................................... 6 6 Proposals........................................................ 6 7 Design............................................................ 8 8 Sootblowers.................................................. 18 9 Air Preheaters............................................... 21 10 Economizers................................................. 21 11 Firing System Equipment............................. 22 12 Forced Draft Fans........................................ 26 13 Ductwork...................................................... 28 14 Stacks........................................................... 29 15 Insulation and Refractories.......................... 29

Document Responsibility: Heat Transfer Equipment 32-SAMSS-021

Issue Date: 18 January 2010

Next Planned Update: 18 January 2015 Manufacture of Industrial Boilers

of 2

Table of Contents (cont'd)

16 Noise Attenuation......................................... 30 17 Connections, Boiler Trim and Instruments... 30 18 Burner Management Systems...................... 34 19 Painting........................................................ 34 20 Fabrication.................................................... 34 21 Nondestructive Testing................................. 35 22 Postweld Heat Treatment............................. 36 23 Inspection and Equipment Testing............... 36 24 Nameplates and Stampings......................... 38 25 Preparation for Shipment............................. 38 26 Drawings, Calculations and Data................. 40 27 Life Cycle Cost Evaluation........................... 40

1 Scope

1.1 This specification covers the minimum mandatory requirements for the

manufacture of industrial type watertube fire, (herein referred to as boilers), that

are fueled by either oil, or gas.

1.2 This specification includes requirements for the thermal sizing, mechanical

design, shop fabrication, field fabrication, installation, and testing of boilers.

1.3 The requirements in this specification are in addition to and supplement the

requirements of the Boiler and Pressure Vessel Code, ASME SEC I, (herein

referred to as the Code).

2 Conflicts and Deviations

2.1 Any conflicts between this specification and other applicable Saudi Aramco

Materials Systems Specifications (SAMSSs), Saudi Aramco Engineering

Standards (SAESs), Standard Drawings (SASDs), or industry standards, codes,

and forms shall be resolved in writing by the Company or Buyer Representative

through the Manager, Consulting Services Department of Saudi Aramco,

Dhahran.

2.2 Direct all requests to deviate from this specification in writing to the Company or

Buyer Representative, who shall follow internal company procedure SAEP-302

and forward such requests to the Manager, Consulting Services Department of

Saudi Aramco, Dhahran.

http://standards/docs/SAEP/PDF/SAEP-302.PDF




of 3

3 References

Materials or equipment supplied to this specification shall comply with the latest edition

of the references listed below, unless otherwise noted.

3.1 Saudi Aramco References

Saudi Aramco Engineering Procedures

SAEP-302 Instructions for Obtaining a Waiver of a

Mandatory Saudi Aramco Engineering

Requirement

SAEP-341 Equipment Life Cycle Cost Procedure

Saudi Aramco Engineering Standards

SAES-A-004 Pressure Testing

SAES-A-005 Safety Instruction Sheet

SAES-A-102 Air Pollutant Emission Source Control

SAES-A-112 Meteorological and Seismic Design Data

SAES-B-054 Access, Egress, and Material Handling for Plant

Facilities

SAES-H-001 Selection Requirements for Industrial Coatings

SAES-H-100 Painting Requirements for Industrial Facilities

SAES-H-101 Approved Protective Coating Systems

SAES-J-602 Burner Management, Combustion, and Waterside

Control Systems for Watertube Boilers

SAES-N-001 Basic Criteria, External Insulation

SAES-N-100 Refractory Systems

SAES-N-110 Installation Requirements - Castable Refractory

SAES-N-130 Installation Requirements - Fireclay Bricks

SAES-N-140 Installation Requirements - Refractory Ceramic

Fiber

Saudi Aramco Materials System Specifications

17-SAMSS-503 NEMA Frame Motors

32-SAMSS-009 General Purpose Steam Turbines



http://standards/docs/SAES/PDF/SAES-A-004.PDF




http://standards/docs/SAES/PDF/SAES-B-054.PDF

http://standards/docs/SAES/PDF/SAES-H-001.PDF



http://standards/docs/SAES/PDF/SAES-J-602.PDF

http://standards/docs/SAES/PDF/SAES-N-001.PDF





http://standards/docs/SAMSS/PDF/17-SAMSS-503.PDF





of 4

34-SAMSS-611 Safety Relief Valves, Conventional and Balanced

Types

34-SAMSS-617 Fire Monitoring Systems

34-SAMSS-619 Flame Monitoring and Burner Management

Systems

34-SAMSS-830 Programmable Logic Controllers

Saudi Aramco Inspection Requirements

Form 175-321300 Boiler: Power; Water Tube

Saudi Aramco Forms and Data Sheets

Form 7305-ENG Equipment Noise Data Sheet

Form 9570-ENG Safety Instruction Sheet

Form SDS-ME 9550 Watertube Boiler Smart Data Sheets

Form SA-F-002 Pre-commissioning Boilers

Form NMR-7913 Non-material Requirements for Industrial

Watertube Boilers

3.2 Industry Codes and Standards

American Institute of Steel Construction

AISC 325 Steel Construction Manual

AISC 326 Detailing for Steel Construction

Air Movement and Control Association, Inc.

AMCA 210 Laboratory Methods of Testing Fans for Rating

American Society of Civil Engineers

ASCE 7 Minimum Design Loads for Buildings and Other

Structures

American Society of Mechanical Engineers

ASME PTC 4 Steam Generating Units

ASME SEC I Power Boilers

ASME SEC II Material, Part D

ASME SEC V Nondestructive Examination

ASME SEC VIII Rules for Construction of Pressure Vessels





http://standards/docs/Inspection_Requirements/PDF/175-321300.PDF

http://standards/docs/Forms_Data_Sheets/XLS/SA-7305.XLS


http://standards/docs/Smart_Data_Sheets/XLS/SDS-ME-09550.XLS

http://standards/docs/Precommissioning/DOC/SA-F-002.DOC

http://standards/docs/Nonmaterial_Requirements/PDF/SA-7913.PDF




of 5

ASME SEC IX Welding and Brazing Qualifications

American Society for Testing and Materials

ASTM A20 General Requirement for Steel Plates for Pressure

Vessels

ASTM A435 Straight-Beam Ultrasonic Examination of Steel

Plate

ASTM D1066 Standard Practice for Sampling Steam

National Fire Protection Association

NFPA 85 Boiler and Combustion System Hazard Code

4 Definitions and Abbreviations

Definitions

Boiler: Within the scope of ASME SEC I, Power Boilers, and this specification.

Boiler Power Piping: Within the scope of ASME SEC I, Power Boilers, Figures PG-

58.3.1 and PG-58.3.2, and this specification.

Boiler Supplier: The Company responsible for manufacturing boilers in accordance

with the requirements of this specification.

Engineering Company: The company responsible for specifying the design

requirements for boilers on the data sheet

EPRS: Effective projected radiant surface, is the projected area of the walls, roof, and

floor of the furnace enclosure, including the furnace exit area.

Furnace Volume: The cubic contents of space provided for the combustion of fuels.

Heating Surface: The flat projected area, excluding refractory covered surfaces.

Saudi Aramco Engineer: The Supervisor of the Heat Transfer Systems Unit,

Consulting Services Department, Dhahran.

Saudi Aramco Inspector: The person or company authorized by the Saudi Aramco

Inspection Department to inspect boilers to the requirements of this specification.

Flame Impingement: Direct contact between a flame and a tube.

ADCT: Acid Dew point Calculated Temperature. It shall be calculated on the basis of

5% conversion of sulfur dioxide to sulfur trioxide.




of 6

Abbreviations (Levels and Rating)

HHWL: High-High Water Level ESD

HWL: High Water Level Alarm

LLWL: Low-Low Water Level ESD

LWL: Low Water Level Alarm

MCR: Maximum Continuous Rating

NLL: Normal Water Level

5 Responsibilities

5.1 The Boiler Supplier is responsible for the thermal design, mechanical design,

(Code and structural calculations), supply of all materials, fabrication,

inspection, testing, and preparation for shipment, in accordance with the Code,

the completed data sheet and this specification.

5.2 The Engineering Company is responsible for specifying the design requirements

for boilers, as noted on the data sheet. The balance of boiler instrumentation in

accordance with SAES-J-602, for both field and control room instruments

including the following shall be supplied by the Boiler Supplier:

1) Combustion and feedwater regulatory controls

2) Burner management systems

3) Steam drum level indication and shutdown instruments

4) Sootblower controls

5) Combustion and waterside analyzers

6) Desuperheater controls

7) Flue gas analyzers (CO, NOx, O2)

8) All instrument connections

9) Combustion air flow elements

10) Connections for flame monitors, including: scanners, receivers and

mountings for junction boxes

11) Soot Blower hardware

12) Thermowells

6 Proposals

6.1 General





of 7

6.1.1 The Boiler Supplier proposal shall be based on details for individual

boilers as outlined on the data sheet.

6.1.2 The Boiler Supplier may offer an alternative design, but must quote on

the base inquiry documents.

6.1.3 The Boiler Supplier proposal shall include a detailed description of any

exception to the requirements of this specification and referenced

industry standards herein.

6.1.4 The Boiler Supplier shall advise the Saudi Aramco Engineer when Boiler

Supplier has any part of a stress analysis executed by a third party.

6.1.5 No proof testing shall be permitted unless specifically approved by the

Saudi Aramco Engineer.

6.1.6 Application of Code Cases to the Supplier of boilers requires approval of

the Saudi Aramco Engineer.

6.2 Detailed Requirements

The Boiler Supplier is to supply the following information with the proposal.

This information is necessary and will be used to complete the technical

evaluation of the quotation. The quotation will be technically unacceptable if

any of the information required is not included.

1) A completed data sheet.

2) A complete boiler supplier performance sheet including heat libration

calculation for furnace sizing at 25%, 50%, 75%, and 100% MCR.

3) Minimum and average Circulation ratios for all circuit diagrams.

4) A list of users operating boilers of the same design and under similar

operating conditions.

5) Sizes of observation ports.

6) The pressure and flowrate required for desuperheater spraywater.

7) Dimensional drawing(s) showing typical internals of drums, materials of

drums and headers, inside diameters, drum and header thicknesses, water

and steam circuit arrangements, furnace configuration, burner locations,

flue gas and air duct arrangements.

8) Typical cross-sectional sketch of steam drums showing the location of

internals, all water levels, and the highest downcomer. The sketch shall




of 8

also show the useful water volume in the steam drum below the NWL,

LWL, and LLWL ESD.

9) Locations of access doors, observation ports, platforms, stairways, and

ladders on a general arrangement type drawing.

10) Acid dewpoint temperature against acid dew point corrosion.

11) Maximum Flame profile dimensions for all specified fuels or combination

of fuels

12) Typical Burner general arrangement drawings with a turn down ratio.

13) Maximum Atomizing steam flow and steam/oil pressure differential

requirements.

14) A completed noise data sheet (Form 7305-ENG) with a detailed

description of acoustical design.

6.3 Performance Guarantees

The following shall be guaranteed for the length of the warranty period specified

in the purchase order or contract documents:

1) Superheater outlet pressure and temperature downstream of the non-return

valve as specified on the data sheet operating between 25% and 100% MCR.

2) Efficiency at 25%, 50%, 75% and 100% MCR with steam conditions and

fuels fired as specified.

3) Unless otherwise specified on the data sheet, a maximum concentration of

100 ppb (parts per billion) total dissolved solids (TDS) and 20 ppb each of

sodium and silica in saturated steam at any load within a boiler's controlled

range when firing any fuel or combination of fuels specified on the data

sheet, provided that ASME BFW quality is met.

4) A controlled flame at all loads to comply with definition of flame

impingement.

5) Stable flame within operation of the boiler from start-up to 100% MCR.

when firing any of the fuels specified on the data sheet.

6) Maximum % load achievable with stable flame- when firing any fuel or

combination of fuels specified and with one burner out of service.

7) Smooth operation in either direction with a stable flame over the complete

operating range with a rate of change in steam demand of 10% MCR per

minute, and without actuating of the LLWL ESD or HHWL ESD.





of 9

8) Flue gas emission levels at operating range of 25% to 100% MCR.

9) Sound levels at normal operating conditions.

7 Design

7.1 General

7.1.1 The design of boilers, boiler piping, and associated equipment shall

conform to the Code, and the completed data sheet.

7.1.2 Equipment and components of standard manufacture shall be provided

to ensure the availability of spare parts. Components need not be

products of the Boiler Supplier, however, the Boiler Supplier shall

assume full responsibility for all components supplied regardless of

their source.

7.1.3 The design of boilers auxiliary components located outdoors shall be

suitable for continuous operation at the summer design temperature for

the site, as specified in SAES-A-112.

7.1.4 Regardless of climatic conditions, all external surfaces shall be self-

draining and protected against corrosion. Open covers (roof and sides

only) shall be provided over firing aisles.

7.1.5 Boilers shall be designed to operate continuously in the automatic

control mode, but with manual control override capabilities, under all

conditions specified on the data sheets.

7.1.6 Boilers and auxiliaries, including control instrumentation, shall be

designed for continuous operation during electrical power outages

through an uninterrupted power supply system (to be provided by

others). The Boiler Manufacturer shall submit an estimate of the

electrical power required.

7.1.7 Boiler auxiliaries shall be capable of sustained operation in automatic

control mode between 25% and 100% MCR for a minimum period of

two years between shutdowns required for the complete testing and

inspection (T&I) of a boiler.

7.1.8 Boilers and auxiliaries shall be capable of accommodating a rate of

change of 10% MCR per minute over the control range of the boiler,

for both an increasing and decreasing steam demand, without causing a

level shutdown or water carryover during the transient condition.





of 10

7.1.9 Circulation calculations at100% MCR shall be prepared and submitted

by the Boiler Supplier for review.

7.1.10 For shipping shop-assembled units (packaged boilers), the boiler,

burners, all necessary appurtenances, and auxiliary equipment (except

fans, drivers, air preheater, economizer, panels for local controls and

burner management systems) shall be mounted on an integral steel

base to provide a complete, self-contained steam generating unit. All

vibration-sensitive equipment shall be shock-mounted.

7.1.11 Furnaces and gas passes shall be designed to prevent dead-ended or

poorly ventilated pockets where combustibles might accumulate and

cause an explosion upon ignition.

7.1.12 Gas passes through furnaces, superheaters and convective heat transfer

surfaces, as well as air and flue gas ducts, shall be designed and

arranged to prevent vibrations from vortex shedding, sootblower

impact loadings, and turbulence. Boiler Supplier shall submit vibration

calculations including flow induced and acoustical vibration.

7.1.13 All outside water walls and furnace division walls shall be of the

membrane wall design.

7.1.14 Gaps between tubes shall be proportional to the tube OD, and shall not

exceed 25 mm in the firebox. Fins (strips) shall be at least 6 mm thick.

Tangent tube welded walls are not acceptable. Any deviation in fin

dimensions shall be identified in the proposal and shall be supported by

fin temperature gradient and stress calculations in the design phase.

7.1.15 All water, steam and fuel piping shall extend 1.0 m beyond the battery

limits of the boiler, exact locations shall be specified by the

Engineering Company.

7.1.16 Space and access shall be provided for the inspection, cleaning,

removal, and maintenance of tube bundles, headers, retractable burner

parts, valves, pumps, fans, turbines, and motor drivers. The boiler

floor casing shall be a minimum of 1 m above grade.

7.1.17 Guards or personal protection type insulation shall be provided around

operating areas where exposed surfaces are hotter than 65°C.

7.1.18 Facilities shall be provided for the complete draining of all water from

the fire side of boiler units after washing. Drains openings shall be a

minimum of 75 mm diameter and be sealed against overheating and

escape of flue gases.




of 11

7.1.19 Enclosures for instrumentation and electrical equipment shall be

selected for the area classification specified on the data sheet.

7.2 Corrosion Allowances

Pressure components other than tubes shall have a minimum corrosion

allowance of 1.0 mm.

7.3 Furnaces

7.3.1 The dimensions and design of furnaces shall be such that complete

combustion of fuels take place within the furnace limits without flame

impingement on sidewalls, roofs, and front walls.

7.3.2 Based on the highest heating values of the fuels, the maximum heat

release at 100% MCR in a furnace of watertube boiler type shall be

designed within the following parameters:

1) The net heat liberation within a furnace volume shall not exceed

620-kW/ m³ (60,000 Btu/hr-ft³) for liquid fuels, 15 API gravity

and heavier, or 820-kW/m³ (80,000 Btu/hr-ft³) for gaseous fuels

and liquid fuels, lighter than 15 API gravity.

2) The net heat absorption rate shall not exceed 470 kW/m²

(150,000 Btu/hr-ft²) of the effective projected radiant surface

(EPRS) for all fuels.

3) Credit for tile-covered floor tubes shall not exceed 10% of the

projected floor area.

7.3.3 Self-closing observation ports having minimum dimensions of 50 x

100 mm or a 100 mm in diameter shall be provided. Ports shall be of

the guillotine design and shall be air-purged for self-cleaning and

cooling.

7.3.4 The number, size, and location of ports shall ensure the visibility of all

burner tips, furnace rear walls, side walls, furnace exit areas, and

furnace roofs.

7.4 Superheaters

7.4.1 Superheaters shall be located such that inlet tubes are not located in

regions of highest flue gas temperatures.

7.4.2 Superheaters may be an all-welded convection or radiant-convection,

located outside furnaces. When located within direct view of burners a




of 12

minimum of two rows of staggered screen tubes shall be provided

between the superheater and furnace.

7.4.3 Flow equalization through superheater tubes shall be achieved by the

sizing of tubes, inlet header, and outlet headers. Tube inlet restrictions,

including swaging, is not permitted.

7.4.4 Desuperheater water flow should not exceed 5% of steam flow. In

case where more percentage is required the steam temperature down

stream the attemperator shall be higher by 10C above saturation

temperature.

7.4.5 Superheater elements shall be located and supported to prevent

vibration, sagging, and misalignment.

7.4.6 Superheater headers shall be located outside gas spaces.

Superheater interconnecting piping shall be provided with,

thermowell,and temperature transmitter. Superheater outlet piping

shall be provided with connections for safety valves and startup vent,

test gage, pressure transmitter, thermowell, temperature transmitter and

pressure gage connections. All superheater outlet piping connections

shall be located upstream ofthe start up vent.

7.4.7 The startup vent and its discharge stack shall be sized for not less than

25% MCR steam flow, and shall be provided with a silencer. Silencers

shall be provided with suitable drains for condensate removal, and

piped to sewer.

7.4.8 Superheater tubes shall be arranged so that sootblowers can effectively

remove soot from the outside surfaces of tubes. Superheater tubes

shall be arranged to prevent soot bridging and plugging gas passages.

7.5 Desuperheaters

7.5.1 Desuperheaters shall be of the water-spray design.

7.5.2 A spray-type desuperheater mixing chamber with an alloy steel liner

shall be provided.

7.6 Steam Generating and Superheater Tubes

7.6.1 All tubes shall be seamless steel or electric resistance welded (ERW)

steel. ERW tubes shall not be used in superheaters.

7.6.2 All tubes shall have a minimum outside diameter of 38 mm.




of 13

7.6.3 Tube material shall be selected based on the highest anticipated metal

temperatures and flue gas composition.

7.6.4 Tube configurations shall allow the free natural circulation of water

and steam, in the proper direction, at all loads, and installed to allow

complete draining of each tube.

7.6.5 Tubes to boiler drums shall be attached by rolling for drums.

7.6.6 All vertical tubes shall be supported or guided, or both, to prevent

bowing and vibration, and to permit expansion.

7.6.7 The minimum wall thicknesses of tubes shall be: 4 mm for 3" OD

tubes and 3 mm for 2"OD tubes and below.

7.6.8 Exposed portions of drums and headers shall be covered with

firebricks or castable refractory.

7.6.9 Horizontal (less than 3 degrees) tubes located in furnace floors shall be

covered by firebricks, 50 mm minimum thickness.

7.7 Baffles

7.7.1 The use of baffles shall be minimized and refractory baffles are

prohibited.

7.7.2 Baffles shall be manufactured of heat-resistant alloy steel and capable

of withstanding gas temperatures and sulfur content under maximum

load conditions.

7.7.3 Baffle walls shall be designed with gas-tight design to prevent gas

bypassing.

7.7.4 All baffles shall be accessible for inspection and repair without

dismantling of casings.

7.8 Drums and Headers

7.8.1 Design pressure shall be at least 5% or 100 kPa (15 psig), above

maximum operating drum pressure, whichever is the greater.

7.8.2 Downcomers and internals shall be designed to ensure positive

circulation under all loads.

7.8.3 Steam drum sizing shall satisfy the following criteria:




of 14

1) The steam space shall be adequately sized to contain steam

separation equipment necessary to attain the guaranteed steam

purity specified throughout the control range.

2) The water holding capacity between the LWL and LLWL shall

be sufficient to sustain one minute evaporation at MCR with no

feedwater flow.

3) The LLWL shall be located not less than 50 mm above the top of

the highest downcomer.

4) A rise in water level (swell) above the NWL resulting from the

requirements specified in paragraph 7.1.9 shall not cause a

carryover or actuation of the HWL alarm.

5) A fall in water level (shrinkage) below the NWL resulting from

the requirements specified in paragraph 7.1.9 shall not cause the

actuation of the LWL alarm.

7.8.4 When intermediate headers are required within a circulating circuit,

restrictions to boiler circulation caused by headers shall be considered.

Headers shall be protected from direct heat or radiant heat from flue

gases.

7.8.5 Drum connections shall be a minimum of ¾ inch NPS.

7.8.6 The wall thickness of connections up to and including 2 inch NPS shall

be schedule 160 minimum.

7.8.7 Pipe sizes of 1¼ inch, 5 inch, and 7 inch NPS shall not be used.

7.8.8 A manway shall be provided at both ends of steam and water drums

and provided with hinged covers.

7.8.9 Header handholes shall be provided.

7.8.10 Drum connections shall be in accordance with Table 1.

Table 1 – Drum Connections

Service Description Design Pressure Type of

End-Connection

Steam outlets All Welded

Safety valves All Flanged

Chemical feed with thermal sleeve

All Flanged




of 15

Service Description Design Pressure Type of

End-Connection

Feedwater inlet with thermal sleeve

All Welded

Water columns, lower connection with thermal sleeve

Under 4.48 MPa (650 psig) 4.48 MPa (650 psi) and above

Welded

Steam pressure gages Under 4.48 MPa (650 psig) 4.48 MPa (650 psi) and above

Flanged Welded

Vents Under 4.48 MPa (650 psig) 4.48 MPa (650 psi) and above

Flanged Welded

Sampling connections Under 4.48 MPa (650 psig) 4.48 MPa (650 psi) and above

Flanged Welded

Continuous and intermittent blowdown

Under 4.48 MPa (650 psig) 4.48 MPa (650 psi) and above

Welded

7.8.11 The facings of flanged connections shall be raised face type.

7.8.12 Steam and water drums shall be welded, postweld heat treated, and

100% radiographically tested in accordance with the Code.

7.8.13 Headers shall be constructed of seamless steel pipe.

7.8.14 Drums with wall thicknesses 50 mm and thicker shall have nozzle

connections as follows:

1) Connections 6 inch NPS and larger per Figures PW-16.1 (q-1),

(q-2), (q-3), or (q-4 ). [100% radiography test to be guaranteed

for (a,) (b), (c), (g), or (h)]

2) Connections 4 inch and less as per (1) above or Figure PW-16.1

(a), (b), (c), (g), or (h)

7.9 Steam Drum Internals

7.9.1 Steam drum internals shall consist of equipment for steam separation,

feedwater distribution, chemical feed distribution, and blowdown.

7.9.2 Steam separation equipment shall consist of centrifugal separators for

boilers above 20 bar operating pressure followed by dryers section

designed to meet the purity of steam specified on the data sheet.

7.9.3 Proposals for other types of steam separation equipment must be

included in the Boiler Manufacturer's proposal and must be

substantiated with test results from commercial units that the steam

purity entering the superheater will not exceed those specified on the

data sheet.




of 16

7.9.4 All internals shall be designed such that they can be removed without

cutting.

7.9.5 The design of chemical feed distribution piping shall comply with the

following:

1) Be extended through steam drums and be of sufficient length to

ensure proper mixing of chemicals

2) Be perforated

3) Closed at the far end with a threaded cap

4) Provided with a thermal sleeve

5) Located in the steam drum to avoid short-circuiting of chemicals

into the continuous blowdown collection system.

7.9.6 Boiler feedwater distribution piping shall be provided with a thermal

sleeve and be extended through the steam drum to assure proper

mixing of the feedwater with the saturated recirculated water so that

thermal shock is avoided.

7.9.7 The design of continuous blowdown internal piping shall comply with

the following:

1) Located in the area with the highest concentration of boiler water

impurities

2) Be extended as far as possible

3) Be perforated with holes not smaller than 10 mm or V-notched

on the top.

7.10 Water Drum Intermittent Blowdown

7.10.1 Intermittent blowdown nozzles shall be located on the lowest point of

water drums. The size shall be based on water quality and operation,

but shall not be less than 1½ inch nor greater than 2 inch NPS.

7.10.2 Separate drain valves shall be provided at the lowest point of water

drums as a means for the draining of boilers.

7.11 Settings and Casings

7.11.1 Drains shall be provided at the low-points of furnaces and bank areas

in order to remove flue gas deposits by water washing.




of 17

7.11.2 Boiler enclosures, including air and gas ducting, shall be weatherproof

and shall be pressure tight without buckling or bowing when subjected

to an internal pressure transient of 1.5 times the furnace operating

pressure.

7.11.3 Bolted access doors shall be provided as required for ready access to

all parts of the equipment for cleaning, inspecting, repairing, and

replacing the tubes and headers. Access to the furnace through burner

openings is not acceptable. Access doors shall be easy to enter from

floor levels or platforms, and shall be clear of all obstructions.

7.12 Structural Steel

7.12.1 The Boiler Supplier shall supply the structural steel necessary to

support the entire operating weight of all parts of a boiler, including

future sootblowers and platforming.

7.12.2 Wind speeds, and seismic forces shall be in accordance with

SAES-A-112.

7.12.3 Boilers shall be designed for wind and earthquake loads in accordance

with ASCE 7.

With reference to ASCE 7, the wind Category Classification to be used

in the calculations of wind loads shall be Category III, and the Seismic

Hazard Exposure Group to be used in calculations of earthquake loads

shall be Group III.

Wind pressures shall be assumed to act on the projected surface area and

shall include due allowances for platforms, ladders, piping, insulation,

and supported equipment.

7.12.4 The design metal temperatures of structures shall be the maximum

calculated metal temperature expected for all operating modes with an

average ambient temperature specified in accordance with SAES-A-112.

7.12.5 Structural steel shall be designed and detailed in accordance with

AISC 325 and AISC 326.

7.12.6 Refractory shall not be used to support structural loads.

7.12.7 Platforms with stairways or ladders shall be in accordance with the

requirements of SAES-B-054, and this specification.

7.12.8 As a minimum platforms with stairways or ladders that are not

accessible from ground level shall be provided for the following:



http://standards/docs/SAES/PDF/SAES-B-054.PDF




of 18

1) All stop and non-return valves

2) Superheater, and economizer safety valves

3) Vent, blowdown, drain, and shutoff valves

4) Flue gas draft control and guillotine dampers

5) Access doors, handholes, and manways

6) Burners, sootblowers, and observation ports

7) Fans and fan drivers

8) Instrument and control valves

9) Electrical equipment

10) Stack sampling or monitoring

11) Draft gages

12) Steam Drum instrumentation

7.12.9 Burner platforms shall be provided with at least one stairway and have

access to all other platforms.

7.12.10 Burner platforms shall be arranged to provide easy removal of burner

guns.

7.12.11 Where several levels of burners are installed, each level shall be

provided with a separate platform, with minimum headroom of 2.1 m.

7.13 Materials

7.13.1 All materials shall be in accordance with the ASME SEC II part D and

the selection criteria in this specification for individual components.

7.13.2 Cast iron, or cast steel fittings are not permitted.

7.13.3 When tube support design temperatures exceed 600°C and fuels

contain a vanadium/sodium ratio between 3:1 and 18:1, tube supports

shall be fabricated from high alloy materials: 60% Chromium-40%

Nickel or 50% Chromium-50% Nickel materials. High alloy

components shall not be welded to carbon steel components.

7.14 Valves

Boiler Valves

7.14.1 The selection of gate, globe and check valves shall be in accordance

with the Code.




of 19

Fuel System Valves

7.14.2 All fuel shutoff valves shall be slow-opening, quick-closing, tight shut-

off valves, and shall be certified fire-safe.

7.14.3 Fuel gas and fuel oil shut-off valves shall be either ball or non-

lubricated plug types.

7.14.4 Position indicator handles shall be supplied for all ball and plug type

valves.

8 Sootblowers

8.1 General

8.1.1 When boiler fuels are specified on the data sheet as oil or a

combination of oil and gas, sootblowers shall be provided. When the

fuel is specified as gas only, spaces for the future addition of

sootblowers shall be provided in boiler convection sections.

8.1.2 Rotary sootblowers shall be used in flue gas passes when flue gas

temperature is below 650°C.

8.1.3 Retractable sootblowers shall be used in flue gas passes when flue gas

temperature is above 650°C.

8.1.4 The Boiler Supplier is responsible for providing a complete and

effective sootblowing system designed to remove soot and other

unfused deposits from all convective heat transfer surfaces.

8.1.5 Sootblowers shall be fully automatic with selected sequential control

and manual override capabilities for individual sootblowers.

8.1.6 Each sootblower shall be easily maintainable, with accessible

lubrication fittings at all required lubrication points.

8.1.7 Sootblower entrance ports shall be protected with 3 mm Type 304

stainless steel sleeves.

8.1.8 The sootblower manufacturer's design shall be substantiated by at least

two years of satisfactory experience in comparable service.

8.1.9 A steam flow measuring device as designed by the Design Engineer

shall be installed in sootblower steam supply lines to each boiler.




of 20

8.1.10 Sootblowers shall be provided with connections for water washing of

boilers.

8.2 Piping

8.2.1 The design of sootblower piping shall be arranged so that condensate

buildup drains away from sootblower heads.

8.2.2 Drain valves shall be interlocked with the control valve to ensure that

upstream condensate is drained during warm-up and prior to the

operation of sootblowers.

8.3 Instrumentation and Controls

8.3.1 Each sootblower shall be provided with individual controls to allow the

selection of either manual or automatic operation.

8.3.2 Automatic control shall be obtained via a programmable logic

controller designed and specified by the Design Engineer in

accordance with 34-SAMSS-830.

8.3.3 Initiation of operating modes shall be prevented until steam supply

systems have warmed-up, all condensate has been drained, and steam

pressure has been established upstream of the sootblower control

valves.

8.3.4 The system shall be provided to prevent the start of a sootblower cycle

until any other operating sootblower has completed its cycle.

8.3.5 Automatic mode of operation shall incorporate the following functions:

1) Enable the lockout of any sootblower from normal operating

sequence.

2) Enable the sequence to be "held" at any point in the sequence by

operator intervention, and allow sootblowers to operate in the

manual or local mode during that "hold" period. On re-selection

of the automatic mode, the sootblower sequence shall continue

from where it was interrupted.

3) After two minutes from the initiation of any emergency stop

signal, automatically retracts any operating retractable

sootblower and shuts down the system to a safe condition.

8.3.6 The following are the minimum indications of system status that shall

be provided:





of 21

1) The mode of operation selected

2) When the system is running under automatic sequential control

3) Individual sootblower in operation

4) The direction of travel for individual retractable sootblower

during operation

5) Steam system warm-up period is in progress

6) Steam system warm-up period is completed

7) Any sootblower(s) locked out of the normal operating sequence

8) Open/closed positions of main supply valve

9) Open/closed positions of individual boiler steam supply shutoff

valves

8.3.7 The following are the minimum indications of alarm status:

1) Elapsed time

2) Motor overload

3) Steam pressure

4) Out of sequence

8.3.8 The following shall be provided in control rooms:

1) Alarms and status indications

2) Automatic and manual mode pushbuttons

3) Sootblower selector switches

9 Air Preheaters

9.1 Air preheaters, if cost effective, shall be of the fixed tubesheet recuperative

design.

9.2 Air preheaters shall be shop-prefabricated to minimize field assembly.

9.3 The materials of construction of tubes and tubesheets shall be selected based on

the acid dewpoint corrosion temperature (ADCT) plus 28°C. (The value of the

ADCT shall be calculated on the basis of a 5% conversion of sulfur dioxide to

sulfur trioxide).

9.4 The selection of all other air preheater materials shall be based on flue gas

composition and metal temperatures developed during minimum load operation

at minimum ambient air temperature.




of 22

9.5 All pipe and pipe fittings shall be of steel construction.

10 Economizers

10.1 General

10.1.1 Economizers shall be provided and designed to avoid steaming at all

loads.

10.1.3 Economizers shall be made of Carbon Steel.

10.1.4 Water bypass with double block valves shall be provided for the

economizer to allow emergency operation of the boiler in cases where

the economizer is out of service. Economizer shall be provided with a

block valve and a safety valve.

10.2 Economizer Tubes and Tubesheets

10.2.1 Tubes shall be arranged in either staggered or in-line rows to allow for

higher boiler performance.

10.2.2 Finned tubes, with a maximum of six fins per 25 mm, shall be used.

The fins shall be attached by high-frequency continuous resistance

welding. The fin thickness shall be a minimum of 1.25 mm and the fin

height shall not exceed 25 mm.

10.2.3 Finned tubes with a maximum of 4 fins per 25 mm shall be used when

firing liquid fuels.

10.2.4 Serrated fins shall not be used when firing liquid fuel.

10.2.5 The minimum design metal temperature of tubes and tubesheets shall

be 15°C above the calculated ADCT.

10.3 Enclosures

10.3.1 Where size and shipping facilities permit, economizers and enclosures

shall be prefabricated to allow for field installation with minimum

assembly and welding.

10.3.2 Coil supports may be manufactured from carbon steel when the design

metal temperature is less than 425°C and flue gas is sulfur-free.

11 Firing System Equipment

11.1 General




of 23

11.1.1 Burners shall be of the forced draft type designed to operate

continuously over the specified turndown range.

11.1.2 Flame profiles of all burners shall be contained within the confines of

the furnace without flame impingement on walls, roof, floor, or exit

screen, and without flame penetration through the exit screen to the

superheater space. Take ABMA's definition and put it instead and we

will add it in the definitions section.

11.1.3 The Boiler Supplier shall provide optical flame scanners to each of the

burner assemblies as detailed by the Design Engineer in accordance

with SAES-J-602 and 34-SAMSS-617.

11.1.4 Burners shall be capable of covering all boiler loads from start up to

100% MCR with stable flame. Turndown shall be achieved

automatically, without changing burner tips or impairing flame

stability.

11.1.5 Burners controls shall be designed to facilitate rapid changeover

between fuel types.

11.1.6 Flue gas shall satisfy emission requirements as specified in the data

sheet at operating conditions between 25% to 100% MCR.

11.1.7 Burner and fuel system design shall permit safe fuel switching during

operation and sudden trip of a burner.

11.1.8 Burners shall be designed to minimize exposure to furnace radiation.

Burner components exposed to furnace radiation shall be fabricated

from heat-resistant alloys.

11.1.9 All burner hardware (including piping, tubing, hoses, valves, and

cocks) shall be of steel construction. Cast iron, copper alloys, and

aluminum alloys, are not permitted.

11.1.10 The proposed burner design shall be compatible with the burner

management system in accordance with this specification.

11.1.11 Burners shall be designed to meet sound level limitations as specified

in this specification.

11.1.12 Connections shall be provided to verify combustion air and fuel

balances between burners.

11.1.13 Burner curves shall be submitted and shall show the fuel consumption

over the burner turndown range against fuel pressure required at the






of 24

burner, and burner draft loss (Register Draft Loss) requirement excess

air vs. load, and pressure vs. load, burner pressure vs. MMbtu's.

11.1.14 The air leakage through a closed air register at the rated load shall be a

maximum of 10%

11.1.15 All safety shutoff and vent valves on burner/pilots shall be as specified

by the Design Engineer in accordance with NFPA 85.

11.2 Oil Burner Assembly

11.2.1 Oil burners shall be the high efficiency, with maximum ratio of steam

to fuel oil flow of 1 to 3, atomizing type, and provide uniform

atomization throughout the burner turndown range with an excess air

not more than 15% at MCR

11.2.2 Burners shall not require more than 1034 kPag (150 psig) oil pressure

at the burner.

11.2.3 If the fuel oils specified on the data sheet will require different burner

tips, the burner design shall be such that the only operator action

required to change a burner tip is the withdrawal of a gun after

isolation of the fuel supply.

11.2.4 Positioning and removal of oil gun assemblies shall prevent flashback

when exchanging burner guns.

11.2.5 Oil gun assemblies shall be provided with flexible stainless steel hoses

for fuel oil and atomizing steam.

11.2.6 Air diffusers (swirler) located at the ends of burner positioning pipes

shall be fabricated from heat-resistant alloy.

11.3 Gas Burner Assembly

11.3.1 Gas burners shall be capable of efficiently burning the specified fuels

within the specified range of heating values throughout the burner

turndown range.

11.3.2 Gas burners shall be the high efficiency throughout the burner

turndown range with an excess air not more than 10% at MCR

11.3.3 Gas burners shall be of the multiport design.

11.4 Air Registers

11.4.1 Air register "open" setting shall provide equal distribution of




of 25

combustion air to each burner to assure optimum flame conditions for

the fuel(s) being fired over the turndown range of the burner.

11.4.2 All parts of air registers shall be shielded from furnace radiation and

protected against conducted heat as covered in NFPA 85.

11.5 Pilots

11.5.1 Class 2 or Class 3 gas igniters, as defined in NFPA 85 shall be

supplied.

11.5.2 Pilots shall be the automatic air and gas type, complete with an electric

spark igniter and designed to utilize combustion air supplied by the

main forced draft fan, as specified in NFPA 85.

11.5.3 Pilots shall be blowout proof and capable of attaining ignition while

maximum combustion air flows through the burner.

11.5.4 Pilots shall be designed to resist furnace radiation with the air registers

closed and main burners in operation without cooling air.

11.6 Burner Windboxes

11.6.1 Burner shall be furnished with windboxes, with bolted access doors,

and acoustic insulation where required.

11.6.2 Windboxes shall be provided to assure equal distribution of

combustion air to air registers for each burner.

11.6.3 Where a windbox supplies combustion air to more than two burners,

the Boiler Supplier shall demonstrate the effectiveness of the air

distribution.

11.6.4 A minimum thickness of 5mm is required for the wind box.

11.6.5 All stiffners to the the wind box shall be continuously welded.

11.7 Burner Piping

11.7.1 Burner piping required for oil, gas, and steam including shut-off valves

shall be supplied by the Boiler Supplier.

11.7.2 Tie-ins shall be from the tops of headers.

11.7.3 Fuel headers shall be supplied with blow-down connections.

11.7.4 All piping and valving shall be located, from a single-point entry, for




of 26

each fuel to the fuel rack.

11.7.5 Fuel oil shut-off valves shall be located as close as possible to headers

with no dead legs.

11.7.6 Unless otherwise specified, a strainer with block and bypass valves

shall be supplied for liquid fuels, located in the supply lines to each

boiler. The size of mesh shall be not larger than half of the smallest

orifice diameter in the burner guns.

11.7.7 Hoses shall only be used for atomizing steam and liquid fuels heavier

than 68° API, (0.709 relative density). The design and materials of

hoses shall be as follows:

1) Three ply construction comprising of the following:

a) An inner hose of close pitch corrugated tubing

b) A middle layer of type 321 stainless steel braid

c) An outer layer of interlocked stainless steel armor

2) Either weld-end or flanged connections

3) Hoses are to be installed such that the hose manufacturer's

minimum bend radius is not exceeded, or any moment is applied

while in service.

11.7.8 Piping shall be arranged to ensure that all manually operated valves are

in easy access. Supervisory manually operated valves for each fuel

shall be the last valve before burners and located so that the valve

operator can view the burner flame through the burner observation

ports while operating the valve as per NFPA 85.

11.8 Burner Testing

For non standard burner design a production model of each burner shall be

tested for capacity, flame profile, stability within the turndown range with a

reference list of users. Witness of the test firing is at the discretion of the Saudi

Aramco Inspector.

12 Forced Draft Fans

12.1 General

12.1.1 Fans shall be, low speed type connected to drivers by flexible

couplings with coupling guards.




of 27

12.1.2 Forced draft fans shall be located at ground level and located to permit

easy access to the interior of fan casings and to allow easy removal of

rotors.

12.2 Fan Design

12.2.1 Fans shall be designed for not less than the following conditions:

1) Air flow rated capacity shall be 105% of air flow required for

maximum continuous rating with 15% excess air for fuel oil and

10% excess air for fuel gas.

2) Maximum ambient design temperature and humidity as per

SAES-A-112.

3) Static head shall be 110% of the head required at MCR with 15%

excess air firing for fuel oil and 10% excess air for fuel gas.

4) Operating horsepower, as determined from items (1), (2), and (3)

corrected for density at the minimum ambient design

temperature.

12.2.2 Fans shall be furnished with inlet guide vanes and with a vane drive

arm for connection to the operating source.

12.2.3 Vanes shall be provided with a mechanical stop to prevent airflow

from falling below 25% MCR.

12.2.4 Fans shall be furnished with a double extended shaft, unless specified

otherwise on the data sheet.

12.2.5 Fan housings shall be a minimum of 5 mm thick. The housing shall be

of all-welded construction and shall be equipped with a cleanout door

and a 2 inch NPS drain. Housings shall be constructed to allow for

rotor removal.

12.2.6 Fans shall be provided with split-sleeve bearings and be self-aligning,

oil lubricated, with independent pedestals and soleplates, or antifriction

bearings may be offered as an alternative.

12.2.7 Air intakes of fans located outdoors shall be provided with bird screens

and with means to avoid pickup of rain and wind-driven sand. The

inlet shall also be designed to avoid wind effects on combustion

airflow measuring devices.

12.2.8 If required, air intake and discharge ducts shall be provided with

silencers in order to meet the noise level limitations specified.





of 28

12.3 Fan Drivers

12.3.1 Drivers shall be as specified on the data sheet and shall be in

accordance with the specified electric power supply and steam

conditions.

12.3.2 Turbine drivers shall conform with the requirements of 32-SAMSS-009.

12.3.3 Motor drivers shall conform with the requirements of 17-SAMSS-503.

12.3.4 Geared drives shall be separately coupled units with a minimum

service factor of 1.5. Gear shafts shall be equipped with split-sleeve

bearings. A torsional analysis shall be prepared for geared units.

13 Ductwork

13.1 General

13.1.1 The Boiler supplier shall furnish a complete ductwork system for

combustion air travel from air intake fans to burner windboxes.

13.1.2 The system shall include supports, expansion joints, hangers, access

doors, dampers, isolation plates, and connections for the measurement

of airflow, temperature, and pressure.

13.1.3 Flue gas ducting from the outlet to the stack, with all the necessary

appurtenances, shall be furnished by the Boiler supplier when specified

on the data sheet.

13.2 Design

13.2.1 Ducts for air and flue gas shall be designed, arranged, and installed in a

manner to prevent vibration, distortion, and undue noise.

13.2.2 Ducts shall be airtight and gastight. The maximum velocity of air and

flue gas shall not exceed 20.0 m/s.

13.2.3 Ducts shall be capable of withstanding an internal transient pressure of

14 kPa (2 psi).

13.2.4 The minimum thickness of flue gas ducts shall be 5 mm and air ducts

shall be 5 mm minimum thickness.

13.2.5 Where more than one boiler exhausts to a common stack, an isolating

plate, complete with davits, and flange spreaders, shall be provided in






of 29

the discharge ducting of each boiler. Isolation plates shall be designed

for tight shut-off and maximum fan discharge pressure.

13.2.6 Flanged connections shall be complete with flanges, erection bolts, and

nuts. Flanges shall be sealwelded in the field.

13.2.7 Ductwork shall be shop-fabricated for field assembly, including the

installation of supports required for external insulation or internal

refractory lining.

13.2.8 An expansion joint shall be provided between force draft fans and the

discharge ducting to boiler.

13.2.9 Internal lining shall be provided where the metal temperature is less

than the calculated value for ADCT. Alternately, external insulation

shall be used where applicable.

14 Stacks

14.1 Stacks shall be furnished by the Boiler Supplier.

14.2 Boilers shall be provided with a common self-supported stack. Unless otherwise

specified on the data sheet, the minimum stack height above grade shall be 45 m.

14.3 The Boiler Supplier shall calculate and guarantee emission rates of nitrogen

oxides and sulfur oxides. The emission rates shall be expressed in Lb/MM

BTU's when the boiler is operated at its design rate firing the fuels specified.

Flue gas emissions (NOx, CO, particulates, hydrocarbons, etc.) shall not exceed

the specified levels as per SAES-A-102.

14.4 Where the stack metal temperature at any operating load can be less than the

calculated value for ADCT a 50 mm castable refractory lining shall be provided.

14.5 All external attachments to the shell shall be continuously welded.

14.6 The design of refractory systems shall be in accordance with SAES-N-100.

15 Insulation and Refractories

15.1 General

15.1.1 Headers, drums, air heaters, economizer casings, windboxes, external

superheater headers, exposed tubes, hot gas ducts, hot air ducts, steam

turbines, and other heated and exposed surfaces shall be insulated in

accordance with SAES-N-001.







of 30

15.1.2 The design of refractory systems shall be in accordance with

SAES-N-100.

15.1.3 Refractory shall be installed in accordance with SAES-N-110,

SAES-N-130, and SAES-N-140.

15.2 Ductwork

15.2.1 Corners of insulation on ductwork shall be protected with metal corner

beading. Insulation on ducts shall be properly supported and securely

fastened.

15.2.2 Clips or welding studs for holding wires and bands shall be spaced a

maximum of 450 mm on center. Exposed supports, duct doors, and

other parts that project through the insulated surfaces shall be insulated

for protection of personnel.

15.2.3 Where the metal temperature of flue gas duct, at any operating load, is

less than the calculated value of the ADCT, a 50 mm castable

refractory lining shall be provided. Alternately, external insulation

shall be used where applicable.

16 Noise Attenuation

16.1 The Engineering company shall specify limits for the sound pressure levels

(SPL) and sound power levels (PWL) at the designated locations, on Form

7305-ENG.

16.2 The boiler supplier shall ensure that the required limits as specified for SPL and

PWL can be achieved by supplying test results of a representative boiler.

16.3 Boilers shall be designed and provided with the acoustical treatment necessary

to meet the specified noise levels. This shall include burner mufflers and

acoustical lining for plenums, ducts, and stacks, vent silencer as required.

17 Connections, Boiler Trim and Instruments

17.1 General

17.1.1 The Boiler supplier shall supply all connections and equipment in

accordance with this specification.

17.1.2 All instrument connections, except thermowells, shall be provided with

separate block valves to permit removal of devices without affecting

other active devices.









of 31

17.1.3 Steam drum connections shall be provided for level instrumentation in

accordance with SAES-J-602.

17.1.4 Connections shall be provided for the chemical cleaning of boilers,

superheaters, and economizers.

17.1.5 Drain connections shall be provided for draining all water after

shutdown or boilout. Valves shall be 2 inch NPS minimum and located

at the lowest point on the water drum to allow complete drainage of

boilers in one hour or less at a pressure of 35 kPa g (5 psig).

17.1.6 Connections shall be provided for the quick draining of all

accumulated water in areas of furnaces, superheaters, boiler banks, and

economizers following water washing of external tube surfaces.

17.1.7 A sealing air system shall be provided from forced draft fan discharge

ducts for all burner removal openings, sootblower wall boxes, and

observation ports. Flexible connections between the sealing system

and air supply lines may be used to compensate for differential

expansion.

17.2 Boiler Trim

The minimum boiler trim requirements to be provided by the Boiler supplier,

shall be as follows:

1) Safety valves for drums, superheater outlets, and economizers in

accordance with the requirements of the Code and 34-SAMSS-611.

Valves shall be complete with discharge piping to a point 3 m above the

nearest platform. Safety valves shall be equipped with lifting levers.

2) A steam outlet stop valve and a screw-down non-return valve, each with a

pressure-sealed bonnet and of approved boiler quality. A pressure-

equalizing warm-up line of not less than 2 inch NPS shall be provided

around stop valve.

3) Intermittent blowdown valves, using two valves in series at each

blowdown nozzle. The outside valve shall be quick-opening, except at

water wall headers.

4) Boiler feedwater shutoff and check valves.

5) Boiler vent valves, using two valves in series at each location.

6) Valves for obtaining representative saturated steam samples, using two

valves in series (double block) at least one down stream of SD and one

superheated steam sample downstream of the SH. If the boiler design






of 32

includes a series of small-diameter tubes between the steam drum and

superheater header, the sample points shall be spaced no more than 1.5 m

apart. Sample connections shall be in accordance with ASTM D1066.

7) Continuous blowdown valves, using two valves in series. The downstream

control valve shall be a hand-operated, V-port valve with a micrometer

indicator or a V-port valve with TDS/conductivity control.

8) Chemical feed valves, using two block valves in series and a check valve.

9) Superheater drain and vent valves, using two valves in series at each

location.

10) Lower header drain valves, using two valves in series for each connection.

11) A sample connection with two valves in series for obtaining representative

water samples. The sample connection shall be located upstream of the

continuous blowdown control valve.

12) Lower drum drain valves, using two valves in series at each location.

13) Three sample coolers (in accordance with ASTM D1066), valving and

drainage trough. The sample piping and valving shall be arranged such

that boiler water, saturated steam, and final steam each have a dedicated

cooler.

14) Desuperheater water shutoff and check valves.

15) Sootblower steam valves, using two valves in series at each location.

16) Economizer outlet stop valve and screwdown non-return valve, where a

water bypass is included.

17) Economizer safety valve (in accordance with the Code) if a bypass is

included.

17.3 Pipework

The minimum piping to be supplied by the Boiler supplier shall be as follows:

1) Steam piping from the superheater outlet header to the main stop valve

2) Interconnecting steam piping between superheater stages and the

desuperheater

3) Saturated steam piping from the steam drum to the superheater inlet header

4) Interconnecting piping from the economizer to the steam drum

5) Boiler feedwater piping from the check valve to the economizer inlet header




of 33

6) Complete piping for the sealing air system, from the FD fan to all users

7) Complete piping for the air system from a single point supply connection

to all users

8) All drain piping from the source to 1 m above grade

17.4 Instrumentation and Safety Relief

17.4.1 The minimum instrument requirements shall be in accordance with the

Code and the following:

1) A combination airflow metering element shall be provided in the

forced draft fan inlet or discharge duct. The flowmeter element

shall be located upstream of any air-heater and be either a

multipoint thermal mass flowmeter or a different head venturi or

airfoil section.

Differential head elements shall be capable of generating a

differential head pressure up to 250 mm water gage at maximum

flow.

2) Sample connections for oxygen and combustible analyzers at the

furnace exit, boiler, economizer, and air preheater outlets.

3) Connections for flame monitoring and scanning.

4) Connections for the measurement of opacity, particulate matter,

sulfur dioxide, nitrogen oxides, oxygen, and carbon monoxide

5) Connections for draft gages at fan inlet and discharge, air outlet

of the air preheater, windbox, furnace, boiler outlet, economizer

outlet, flue gas outlet of the air preheater, and stack entry.

6) Thermocouple wells for measuring the steam temperature after

each stage of superheaters, including the steam temperature

before and after the desuperheater. Thermowells shall also be

provided for measuring the temperature of the feedwater out of

the economizer.

7) Thermocouple wells for measuring flue gas temperatures leaving

the furnace, air preheater, boiler, and economizer thermowells for

measuring air temperatures before and after the air preheater and

in the windbox, with provision for purging. The thermocouple

hot junction shall be located to measure the average flue gas

temperature, and shall be shielded to minimize the cooling effects

of the surrounding surfaces.




of 34

17.4.2 All instrumentation shall be in accordance with the Code, NFPA 85,

and SAES-J-602.

17.4.3 Safety relief devices shall be designed in accordance with the Code.

18 Burner Management Systems

18.1 Unless otherwise specified in the purchase order, boiler supplier shall supply a

burner management system in accordance with NFPA 85, SAES-J-602 and

34-SAMSS-619.

18.2 All nozzles, instrument connections, and thermowells for the burner

management system shall be supplied by the Boiler Supplier.

19 Painting

19.1 All exposed surfaces shall be prepared and painted in accordance with

SAES-H-001, SAES-H-100, and SAES-H-101.

19.2 Gasket contact surfaces shall not be painted.

20 Fabrication

20.1 Forming and Assembly

20.1.1 The layout of shell plates, heads, and head plates shall be made in such

a manner that manways, nozzles and their reinforcement are not

located within any weld seams. Manways, nozzles and their

reinforcement shall not be located within 20 mm of any weld seam.

20.1.2 All nozzles and manways shall be ground flush to the inside curvature

of the drums and headers, and inside diameters shall be radiused

smooth.

20.1.3 Where a split-reinforcing pad is required, the weld joining the pad

sections shall be oriented with the circumferential direction of the

shell. Tapped tell-tale holes ¼ inch NPT shall be provided as follows:

1) One hole in all single piece reinforcing pads.

2) Where a pad is split, each segment shall have at least one tapped

hole.

20.1.4 All internal and external nonpressure-welded attachments shall be fully

seal welded and shall have their radiused corners.










of 35

20.2 Welding

All welding shall be in accordance with the requirements of ASME SEC I.

21 Nondestructive Testing

21.1 General

21.1.1 All Nondestructive Testing (NDT) shall be performed in accordance

with the Boiler supplier written procedure prepared in accordance with

ASME SEC V with the scope of NDT and acceptance/rejection criteria

as defined by the Code and this specification.

21.1.2 All NDT on boiler drums which are to be postweld heat-treated shall

be made after postweld heat treatment.

21.1.3 All pressure and nonpressure welds shall be visually inspected.

21.2 Radiographic Testing

21.2.1 Radiographic testing of tube support castings shall be conducted on

any cracks or other indications exposed by liquid penetrant inspection

that exceeds the quality requirements of ASME SEC I, PG-25.

21.2.2 Areas of stress concentration in corners of castings, especially at

support lugs, shall be radiographically inspected. At least two spot

radiographs shall be taken of the lower flanges of each cast tube

support section.

21.2.3 One random spot radiograph shall be made for circumferential weld

and one random radiograph for longitudinal welds of each stack shell

section. In addition, each longitudinal and circumferential welds

intersection shall be radiographed in the circumferential direction.

21.2.4 All personnel performing field radiography at Saudi Aramco facilities,

sites, and concessionary areas shall be in possession of valid permit to

handle and use radioactive ionization materials and equipment.

21.3 Ultrasonic Testing

21.3.1 All butt-welds on boiler piping, 32 mm wall thickness and thicker shall

be ultrasonically tested. Ultrasonic examination and interpretation

shall be in accordance with ASME SEC VIII.

21.3.2 Tubesheets and forgings 50 mm and thicker shall be ultrasonically

tested in accordance with ASTM A435.




of 36

21.4 Magnetic Particle Testing

21.4.1 Beveled edges of carbon steel plates with thicknesses 25 mm and thicker

and all ferrous alloy plates shall be magnetic particle examined for linear

discontinuities. Defects shall not exceed limits as per ASTM A20.

21.4.2 All internal and external welds for all services made using the SMAW

welding process when the nominal thickness of pressured components

is 25 mm and thicker shall be magnetic particle tested.

21.5 Hardness Testing

Weld hardness testing shall be in accordance with the requirements of

ASME SEC I.

22 Postweld Heat Treatment

22.1 Code exemptions for postweld heat treatment of ferritic materials based on the

use of austenitic or nickel-based electrodes are not permitted.

22.2 The maximum postweld heat treating soaking temperature for carbon steel and

C-½ Mo materials shall not exceed the temperature at which the test pieces were

heat treated, as shown on the Mill Test Certificates or 650°C for carbon steel

and 690°C for C-½ Mo.

22.3 The maximum postweld heat treating soaking temperature for low-chrome alloy

steels shall not exceed the tempering temperature at which test pieces and

components were heat treated as shown on Mill Test Certificates, but shall be

not less than 700°C.

22.4 Postweld heat treatment shall follow all welding and repairs but shall be

performed prior to any hydrotest or other load test.

22.5 Postweld heat treating shall be in accordance with the requirements of

ASME SEC I and ASME SEC IX.

23 Inspection and Equipment Testing

23.1 Inspection

23.1.1 All materials and fabrication shall be subject to inspection by the Saudi

Aramco Inspector in accordance with Saudi Aramco Inspection

Requirements Form 175-321300.

23.1.2 Written reports and evaluations of all inspections performed by the

Boiler Supplier shall be made and submitted to the Saudi Aramco

http://standards/docs/Inspection_Requirements/PDF/175-321300.PDF




of 37

Inspector, at a frequency to be determined by the Saudi Aramco

Inspector.

23.1.3 Written reports and evaluations of all inspections performed by the

Boiler Supplier shall be made and submitted to the Saudi Aramco

Inspector, at a frequency to be determined by the Saudi Aramco

Inspector.

23.1.4 Prior to final inspection and pressure testing, the inside and outside of

boilers shall be thoroughly cleaned of all slag, scale, dirt, grit, weld

spatter, paint, oil, etc.

23.1.5 The Saudi Aramco Inspector shall have free access to the work at all

times.

23.1.6 Refractory linings and materials shall be inspected in accordance with

SAES-N-110, SAES-N-130, and SAES-N-140.

23.2 FD Fan Testing

Fans shall be tested by the Boiler Supplier in accordance with AMCA 210 and

the following:

1) No load, full speed run test

2) One Aerodynamic performance test per FD fan type.

23.3 Boiler Performance Testing

23.3.1 A performance test, shall demonstrate complete and smokeless

combustion without flame impingement on the furnace heating surface

or flame penetration through the furnace exit screen, at all loads within

the turndown range, and with any fuel or combination of fuels

available at the time of the test on each boiler.

23.3.2 Boiler efficiency shall be based on the higher heating value of the fuel,

and the tests shall be made in accordance with ASME PTC 4,

Performance Test Code (Abbreviated Method). If the results of a

performance test do not conform in with the guaranteed values, the

Boiler Supplier shall immediately correct deficiencies.

23.3.3 Unless otherwise specified, the acceptance test shall be performed by

the Boiler Supplier representative after commissioning.

23.3.4 In addition to the Code, the following represent the minimum shop

leak tests:







of 38

Hydrostatic test of all pre-assembled pressure-containing sections, in

accordance with the Code and SAES-A-004.

23.3.5 In addition to the Code, the following represent the minimum field leak

tests:

A hydrostatic test of all pressure parts in accordance with the Code,

prior to installation of the casing.

23.3.6 Field pressure testing shall be in accordance with the Code.

23.3.7 After inspection and testing, boilers shall be completely drained of all

liquids.

24 Nameplates and Stampings

24.1 Boilers shall be Code stamped.

24.2 Nameplates and nameplate mounting bracket shall be located such that they will

not be covered by insulation and is easily readable from grade or a platform.

25 Preparation for Shipment

25.1 General

25.1.1 The Boiler Supplier is responsible for preparing materials for shipment

and assuring their arrival on-site in good condition.

25.1.2 All components shall be packed, securely anchored and satisfactorily

protected for their respective shipment methods.

25.1.3 One complete set of installation, operating, and maintenance

instructions necessary for installation shall be packaged and shipped

with the equipment.

25.1.4 Bracing, supports, and rigging connections shall be provided to prevent

damage during shipment, lifting and unloading.

25.1.5 All instruments and valves, including auxiliary systems, shall be

securely mounted, supported, and/or boxed to avoid damage during

shipment.

25.1.6 All exposed finished and machined surfaces, including bolts, shall be

coated with a rust-inhibiting compound.





of 39

25.1.7 Bearings and seal assemblies shall be fully protected against the entry

of moisture and dirt.

25.1.8 Flanged connections and all other machined surfaces shall be protected

by a coating, which is easily removed in the field. Flanges shall be

fitted with a steel or wood cover, 3 mm thick and neoprene gaskets.

25.1.9 Covers shall be securely attached by a minimum of four bolts equally

spaced. For ocean shipment, flanged connections shall also be covered

with heavy duty plastic bags securely taped to the nozzles.

25.1.10 Markings shall be done with water soluble materials that contain no

harmful substances that would attack or harmfully affect coils at both

ambient and operating temperature.

25.1.11 Marking materials shall be free of lead, sulfur, zinc, cadmium,

mercury, chlorine, or any other halogens.

25.1.12 Threaded connections, shall be protected with threaded plugs.

25.2 Internal Protection

25.2.1 The internals of drums and headers shall be protected from corrosion

by use of a nontoxic vapor phase corrosion inhibitor applied at a rate of

1 kg/m³. Desiccants may only be used with approval of the Saudi

Aramco Engineer.

25.2.2 Drums and headers must be sealed vapor tight using metallic covers,

for inhibitors to be effective.

25.2.3 Alternatively, nitrogen blanketing, temporary coatings or a vapor proof

bag with moisture control may be used.

25.3 External Protection

The protection of external surfaces shall be obtained by using one of the

following:

1) A hard temporary preservative which can be removed at site prior to

surface preparation and application of the Saudi Aramco coating and

painting system.

2) Prepare the surface and apply the complete (primer and final coatings)

Saudi Aramco surface preparation, and coating and painting system in the

shop.




of 40

26 Drawings, Calculations and Data

26.1 The Boiler Supplier shall prepare and submit for approval and review the

preliminary and certified drawings and data detailed on Form NMR-7913.

26.2 Drawings and calculations which are approved by the Design Engineer shall not

relieve the Boiler Supplier of responsibilities to comply with the Code, and this

specification.

26.3 The Engineering Company is responsible for the completion of the Safety

Instruction Sheet Saudi Aramco Form 9570-ENG in accordance with

SAES-A-005 and the data on the Boiler Supplier drawings.

27 Life Cycle Cost Evaluation

Unless otherwise approved by the Coordinator, Mechanical Engineering Division,

Consulting Services Department, Quotations for boilers shall be evaluated on the basis

of Life Cycle Cost (LCC) as explained in SAEP-341. This cost is composed of the

initial purchase cost of the Boilers(s) plus the present worth of the fuel consumption

over an assumed operating period of 15 years. The Life Cycle Cost of the Boiler(s)

shall be determined using the following Life Cycle Cost spreadsheets:

LCC-024, Single Fuel Boilers

LCC-024A, Dual Fuel Boilers

The efficiency of the boiler at 100% of the design heat releases shall be guaranteed. If

the actual efficiency during performance tests is found to be less than the guaranteed

efficiency. If not corrected, then the cost of the boiler(s) shall be reduced by an amount

equal to the difference in fuel consumption (MMBTU/hr) for not meeting the

guaranteed efficiency, multiplied by the Evaluation Factor $-hr/MMBTU as given in the

Provided Life Cycle Cost spreadsheets included with boiler data sheet. The maximum

reduction shall not exceed 15% of the initial cost of the boiler(s).

Mathematically:

Single Fuel:

Efficiency Penalty = [actual efficiency - (guaranteed efficiency-0.01)] * L * EF

Commentary Note:

Efficiency values are in decimal representation. 0.01 in the equation is a 1% test tolerance allowed.

EF = PV * EC * AH

http://standards/docs/Nonmaterial_Requirements/PDF/SA-7913.PDF







of 41

Dual Fuel:

Efficiency Penalty = Sum of Efficiency Penalty of all fuels

For each type of fuel the evaluation factor is defined by

EF = PV * EC * T

Where;

L = Boiler Load (Duty) @ normal condition (MMBTU/hr) will be show

on the data sheet.

EF = Evaluation Factor ($-hr/MMBTU) will be shown on the data sheet

that goes with the quotation request

EC = Energy cost in $/MMBTU for each fuel

AH = Annual operating hours

= OF * 8760

OF = Operating Factor, equal 1

PV = Present value factor = 5.85 based on 15% discount rate expressed as a

decimal number and operating period of 15 years.

T = Operating time for each fuel type, in hours

Revision Summary

18 January 2010 Major revision.

32-samss-021

Documents

equipment testing

testing of boilers

firing system equipment

materials system specification

salamah salem

shop fabrication

field fabrication

minimum mandatory requirements