mr p k shrivastava valve_presentation rev1

ValvesValves User’s Perspective & Expectations

Petroleum Refinery and Petrochemicals

By P.K.Shrivastava (Reliance Engineering Associates Limited)

Introduction

Reliance has recently completed major projects comprising of integrated Petroleum Refinery & Petrochemical complex ( JERP )along with Deep Sea Oil & Gas production systems ( KGD6 ).

Installed and put into operation more than 350,000 valves Similar quantum of valves are in use in the existing plants of

RIL group companies which are being maintained .Used almost all types of valve, viz. Gate, Globe, Check,

Butterfly, Ball, Plug etc. Valves for new projects are procured from domestic as well as international markets. (Onshore scope is about 60% for cast steel valves & 5% for forged valves)

Valve Vendor evaluation checklist

Almost all the valves are procured directly from the manufacturers. The vendors were evaluated on the following checkpoints prior to consideration for Order placement :

Design Capability & Technical tie-up/back –ups Range of valves manufactured (Size/MOC & service – wise) ISO 9001 accreditation & API monograms List of Satisfactory clients Service tenure of the valves Manufacturing capacity (including inspection facilities,

Hydro/Pneumatic testing facilities, painting, material identification facilities, etc.)

Casting sourcing procedures Third party Agency & consultants used

Types of Valves Used

Ball5.1%

Butterfly3.7% Check

8.5%

Gate78.3%

Globe3.8%

Plug0.5%

Types of Special Valves Used

Over and above the basic types of valves specified in the earlier slide, following special valves are used :

Metal seated triple offset butterfly valve for general hydrocarbons service in the size range of 10” to 72”

Nozzle check valves Plate type check valves for gas /air services

Cryogenic Gate /Globe /Ball valves with extended spindles

Angle Valves

Needle Valves

Plate type Check Valve

The major advantages of the plate type check valves are :

Reliable and rapid closing action upon or before flow reversal

Minimal pressure drop

Long service life even in pulsating flow environments

Low maintenance

Low Noise

Smooth operation at different duty points

Variable installation position

Compliance with international Standards and directives

Material of Construction used

Carbon Steel86%

LTCS3%

Stainless Steel5%

Alloy Steel4%

Bronze2%

Body Construction types used

Casting39%

Forging61%

MOC wise break-up of Castings

Carbon Steel84%

LTCS5%

Bronze1%

Alloy Steel4%

SS6%

MOC-wise breakup of Forgings

Carbon Steel87%

Bronze2%

Alloy Steel4%

LTCS2%

SS5%

Sizes of Valves used

176,104

42,408

32,444

16,559

6,3281,204

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

1/2" - 1.1/2" 2" 3"-6" 8"-12" 14"-24" 24"-84"

64%

15%

12%

6% 2% 1%

Material of Construction used in KGD6 – Onshore Application

MOC-wise breakup details of 26596 used in KGD6 – Onshore Application

6Mo SS0.9%

SS13.5%

LTCS27.4%

Duplex SS1.6%

Carbon Steel56.5%

Size-Range of valves used in KGD6 – Onshore Application

% Size-wise breakup of 26,596 valves used in KGD6- Onshore Application

1/2" - 1.1/2"49.4%2"-10"

48.5%

>10"2.1%

Size Range UOM Carbon Steel Duplex SS SS LTCS 6Mo SS Total

1/2" - 1.1/2" Each 7924 144 1717 3277 72 13134

2"-10" Each 6682 290 1814 3951 165 12902

>10" Each 429 0 51 72 8 560

Problems Experienced

While there has been some perceived improvement as compared to the quality of valves procured in our earlier Petroleum / Petrochemical projects, there is sufficient scope for the enhancement in the design and overall quality system for the domestic suppliers to focus on.

Major observations related to design and quality of the valves have been illustrated in the subsequent slides. These findings have been summarized on the basis of the problems reported at Jamnagar site from the recently commissioned Jamnagar Export Refinery Project.

Problems encountered in Globe Valves

In case of unidirectional Globe valves designed for flow from over the disc and tested in the same direction Problems were experienced with large size (>10”) valves which could not take the test pressure in the conventional direction. These sort of cases pose operational hazards because these valves may not block the flow from both directions. Our Our suggestion in this regard is to design the valve, with suitable disc profile suggestion in this regard is to design the valve, with suitable disc profile and stem material, such that these could hold the pressure from both the and stem material, such that these could hold the pressure from both the directions.directions.

In case of unidirectional Globe Valves, It may also be noted that the valves designed for flow from under the disc are inherently suitable for flow from both the sides; however, the reverse is not possible unless the valves are designed and tested from both the directions. The subsequent slide comprising of a typical globe valve design in accordance to BS 1873 shall lend more clarity to this point.

Problems encountered in Globe Valve

Problems encountered in Globe Valves

Gland Leakage

Leakage from Seat / Bonnet joints identified during hydrotest prior to plant start-up.

Operational / functional problems during project start-up

Mismatch in body MOC identified during PMI tests at site

Broken stems

Gear Box problems

It may be noted that this sort of problems identified prior to plant start-up had a major impact on meeting the project schedule at the eleventh hour.

Sample case of Problem encountered in a Globe Valve used in By-pass line

One sample case of a failure encountered in a 12” Class 300 Globe valve in a Control Valve By-pass line is worth mentioning as the leakage of the fluid (LCGO) through its gland led eventually led to a fire as shown below :

Sample case of Problem encountered in a Globe Valve used in By-pass line

The major observations on dismantling this valve are listed below:

There were no gland packing which could have been blown away during the leak and subsequent fire.

The guide rod at the bottom was missing – The construction was flimsy even the weld to disc appeared inadequate as checked on another valve of same make.

The bush on which the back seat sits could be opened by hand indicate poor fabrication practice.

The body/bonnet gasket was of grafoil only instead of spiral wool SS316 as per data sheet.

The stem didn’t bend and no scoring marks at gland area.

The disc was in position and remote possibilities of its rotation on its own and flow reduction.

There was also no proof of third party inspection of this valve during hydro-test at the Vendor shop. The inspected valves scope did not mention this valve as part of third party inspection.

Sample case of Problem encountered in a Globe Valve used in By-pass lineThe snaps of the valve internals specified below will give

a better insight to the findings of the failure of the globe valve :

Problems encountered in Gate Valves Gland Leakage and Leakage thru’ bonnet stuffing box found on account of broken packing rings.

Damaged Wedge seating area & damaged guides accounting for problematic wedge movement. There were also cases screwed seat rings which should actually have been seal welded.

Operational / functional problems during project start-up


Castings were not of radiographic quality as Pin-holes in bonnet / Blow holes in body were commonly observed.

Gear Box problems

Body flange thickness was often found to be on the lower side when compared with the dimensional standards. Problems were also faced at site related to the bolting of the flanges as the same were not machined properly.

Problems encountered in Gate Valves

Casting Defects - Blow holes found on new valve bodies

Problems encountered in Ball Valves

Gland Leakage & Leakage through sealant connections.

Gearbox body movement during operation.

Development of cracks near the handle

No Operation –Handle free rotation / Bent spindle

Other operational problems like noise/friction during operation. It is to be noted that these problems of ball valves were all identified in sizes of 10” only.

In case of ball valves for sizes up to 3/4“ installation at site was problematic as the mating flange studs were fouling with valve body bolting .

Problems encountered in Ball Valves

Crack near the handle

Improper bolting leading to improper gasket compression

Problems encountered in Butterfly Valves

Problem of improper lining on body/seat/disc for large size valves (>24” NPS), e.g.. Many cases of liners not extended to the flange face were identifiedFrequent problem of damaged liners, improper bonding of liner with body/discEffective bonding procedure for the EPDM lining on body/disc to be developed Metallurgical issues need to be addressed due to highly corrosive nature of seawater. It may be noted that Cu-based alloys cause problem of galvanic corrosion in the CS pipelines with saline service


Soft Seat coming out of position during opening after hydrotest of a 42” butterfly valve

Poor quality of coating on the disc, coating could not take even a gentle tapping by hand. Lining problems also exist with body lining.


Case of a recent Valve Rubber Lining Failure encountered in JERP


Bolting not possible at tapped holes.Damaged liners & lining problems leading to leakage from seat.Seat passing even at low pressures.Automatic Valve closure without any manual intervention when left in open condition.Operational / functional problems which can pose a severe threat specially in the Fire water lines during emergencies.These problems were identified in valves in the size range from 12” to 72”.

Problems encountered in Check Valves

Wafer type design is not recommended for hydrocarbon services on account of associated leakage hazard in case of accidental fire (due to differential expansion of studs on high temperature services and studs getting exposed to external fire) on account of which there was a requirement of Dual Plate Double Flanged Check Valves where we faced a problem of sourcing the same from domestic market.

As a minimum, where the flanged design is not possible as per API594 due to dimensional limitations, extended face to face dimensions to accommodate fastening of the bolts to be looked into

Retainer-less design should be developed to meet low fugitive emission requirements and also to preclude any leakage hazard

Rubber lined check valves pose similar problems of damage to body/disc lining, as explained in the previous slides for lined butterfly valves


Typical Check Valve designs (API 594) required / Supplied

Required Double Flanged Design

Supplied Wafer Type Design

Suggested Solid Lug Design where dimensional limitations are involved


Seat leakage, Leakage from damper, leakage of hyd oil thru damper were some common leakage problems faced pertaining to Check Valves during the start-up of the Jamnagar Export Refinery Project.

Pin hole / Blow-Hole observed in the valve body.


Operational / Functional problemsSpring & Shaft failure of Nozzle check Valve on the outlet of reciprocating compressor on account of fluctuation of fluid flow.

Sample case of problems in 16", 600# ,Dual Plate Check Valve

The following observations in a 16", 600# ,Dual Plate Check Valve (Body and Disc -SA216 WCB+STL6 Overlay) operating in a Pump discharge line is worth mentioning –A through and through hole at 1 to 2 ‘o’clock position was observed at back side of valve disc.The water jet impingement through disc hole also further eroded the valve body. Radiography of the whole disc was carried and casting defects like shrinkage cracks, porosity and sand inclusion were observed. Taking cue from these findings similar checks were carried on other valves of the same make for this project where the findings were similar at other discs at similar location.The snaps of these valve in the next slide will lend more clarity to this case

Sample case of problems in 16", 600# ,Dual Plate Check Valve

Spring & Shaft failure of Nozzle check Valve

Quality System

The existing system of Quality Control & management at the Vendor’s place seems inadequate/deficient, particularly when it comes to large scale production of quality valves.

There have been many instances of failure at various levels of manufacturing, as mentioned below:

Mix up of metallurgy in alloy steel valves. Many cases have been noticed at the PMI tests conducted at site where the body/bonnet metallurgy are different between what was specified in the requirement and the actual receipt at site. This indicates lack of traceability at shop level and may result in severe accidents once installed in Petrochemical / Petroleum sites involving a fair degree of hazardous services.

Lack of traceability of trim materials’ metallurgy

Perceived failure/inadequacy of final inspection at manufacturer shop level by qualified inspectors using fool-proof inspection techniques.

Quality System

The instances Multiple Failures of valves during hydrotest at site (seat/body) are very high, and this causes concern on shop level testingImproper packaging and preservation system before dispatch, which results in damages to valves rendering them unsuitable for application on receipt at site in the course of which the project schedule completion gets affected.Casting Defects have been a major concern. Radiographic quality castings should be a norm. Whereby Castings are out-sourced to other foundries, qualified vendor’s quality control inspector should supervise the entire process to ensure the quality of the castings.Radiography/NDE facilities for higher rated valves having high thickness need to be developed

Valve Installation SOP work-flow

Design Development & Facility Enhancement Scope

With the increasing plant capacities, current technologies require large size and high rated valves for which there is limitation on available capacity in India. Subsequent to execution of many Mega Projects, we feel that there is a need for more R&D for the development of high performance valves and valves having special feature, as specified below :

Dual plate wafer type check valves with retainer-less design to address fugitive emission issuesDual plate check valves with double flanged/solid lug type designSwing check valves cast-in hinge arrangementLarge size swing check valves with actuated/hydraulic dampening devices

Design Development & Facility Enhancement Scope

Triple offset butterfly valves in large sizes (>54” NPS)Triple offset butterfly valves with solid metal disc-seat ringLarge size (>24” NPS) butterfly valves for seawater service, requiring rubber liningImproved Competiveness & Capacity for forged valves Guided disc feature must be included in all Globe valvesDevelopment of Ball and Spring type check valvesUWL certification of valvesDesign of valves with extension spindle Chain wheel operated valvesLimitation in availability of ball valves manufacturing facilitiesDevelopment of Nozzle Check ValvesImprovement in Site Support System

Future Projects & Our Expectations

Keeping in view the fast track nature of projects, we expect the Domestic Valve industry to come forward with the three pronged challenges of : Manufacturing quality valves in the shortest possible delivery lead time. Competitive pricing without compromising on quality (lest, India may loose out on the market like China). Effective Service – after –sales, which can go a long way in the smooth commissioning of the projects.

Thank You

mr p k shrivastava valve_presentation rev1

Documents

special valves

basic types of valves

cast steel valves

inspection facilities

major projects

castingcarbon steel83

general hydrocarbons

sizemoc service wiseiso