bray/ vaas bidirectional - industrial valves | control valves & … knife gate... · 2017. 8....

Bray/ VAASBidirectional - Perimeter Seat Series Knife Gate Valve

740/752/755/755P/755R SeriesOperation and Maintenance Manual

Table of Contents

Definition of Terms 1

Safety Instructions 1

Introduction 2

Unpacking 2

Storage 2

Installation 3

Commissioning 3

Cylinder-Operated Valves 3

Manual Valves 3

Maintenance 4

Lubrication 4

Packing Replacement 5

Seal Replacement 6

Series 740 6

Series 752/755 7

Actuator Maintenance 8

Spare Parts 8

Packing Details 8

Troubleshooting 10

For information on this product and other Bray products please visit us at our web page - www.bray.com.

Bidirectional - Perimeter Seat Series

Operations and Maintenance Manual

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Bidirectional - Perimeter Seat SeriesOperation and Maintenance Manual

Definition of Terms - Safety Instructions

READ AND FOLLOW THESE INSTRUCTIONSSAVE THESE INSTRUCTIONS

DEFINITION OF TERMS

Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury

Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury

NOTICE Used without the safety alert symbol indicates a potential situation which, if not avoided, may result in an undesirable result or state, including property damage

HAZARD-FREE USEThis device left the factory in proper condition to be safely installed and operated in a hazard-free manner The notes and warnings in this document must be observed by the user if this safe condition is to be maintained and hazard-free opera-tion of the device assured

Take all necessary precautions to prevent damage to the valve due to rough handling, impact, or improper storage Do not use abrasive compounds to clean the valve, or scrape metal surfaces with any objects

The control systems in which the valve is installed must have proper safeguards to prevent injury to personnel, or damage to equipment, should failure of system components occur

QUALIFIED PERSONNEL• A qualified person in terms of this document is one who is familiar with the installation, commissioning, and operation

of the device and who has appropriate qualifications, such as:

• Is trained in the operation and maintenance of electrical equipment and systems in accordance with established safety practices

• Is trained or authorized to energize, de-energize, ground, tag, and lock electrical circuits and equipment in accordance with established safety practices

• Is trained in the proper use and care of personal protective equipment (PPE) in accordance with established safety practices

• Is trained in first aid

• In cases where the device is installed in a potentially explosive (hazardous) location – is trained in the commissioning, operation, and maintenance of equipment in hazardous locations

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The valve must only be installed, commissioned, operated, and repaired by qualified personnel.

The device generates a large mechanical force during normal operation.

All installation, commissioning, operation, and maintenance must be performed under strict observation of all applicable codes, standards, and safety regulations.

Observe all applicable safety regulations for valves installed in potentially explosive (hazardous) locations.

INTRODUCTIONThe Bray/ VAAS Series 740/752/755/755P/755R provides repeatable bidirectional shutoff in a rugged cast body

Featuring soft seating, the Bray/ VAAS Bidirectional - Perimeter Seat gate valve caters to all types of bidirectional sealing requirements across a wide range of industries

Additional information about Bidirectional - Perimeter Seat Series valves – including application data, engineering specifica-tions, and actuator selection is available from your Bray/ VAAS distributor or sales representative

UNPACKINGEnsure the box is not damaged externally Remove the valve from the packaging and check for any damage to the valve and its components during transit

Valve size and brief material specification of body (markings such as “SS” or “DI”) are marked on the valve body Stainless steel nameplate (below) fixed on to the yoke of valve contains most of the relevant information on the valve including Bray/VAAS work order number and unique serial number of the valve These details should be quoted for all requirements of service and spares

SERIAL NUMBER

SIZE MODEL FLG. DRILL BODY GATE

SEAT PACKING CWP MAX TEMP

STORAGEWrap the valve with a polyethylene cover Cover the ports for pneumatic actuator/accessories with plastic caps Store these valves in the same packing indoors and without direct exposure to the environment

If the valve is to be stored for a long period of time before installation, it should be stored in a vertical position (preferable) and in a cool, clean area to prevent damaging effects on the packing

Gate should be off the seat to prevent compression set

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INSTALLATION

• Valves can be mounted with flow in both directions

• On horizontal lines, if there is a possibility of particles/solids settling at the bottom, it is preferable to install the valve so that the stem is above horizontal/inclined/vertical

• Install the valve between flanges using fasteners & gaskets

• Bolt holes in the chest area are always blind tapped and care should be taken not to bottom the bolts while tightening Refer to GA Drawing/ Technical Bulletin for quantity and size of blind tapped holes on valve chest area If the correct size bolts are not available, use studs and nuts for chest area bolts to avoid damage of body

Support should be used for valves size 8” and over when installed in vertical pipe Failure to do so can result in improper valve operation and/or valve failure

COMMISSIONING GUIDELINES

• Gland packing is tightened to hold the specified pressure and tested for no leakage before dispatch However, this may require some adjustment at site due to loosening in transit etc

• Check for gland leakage after the valve is subjected to pressure and if any leak is observed, tighten the gland uniformly in a cris-cross pattern until the leakage stops

Wrong electrical supply to accessories will damage the equipment Do not over tighten the gland nuts as this may cause excessive friction and premature damage to packing

Cylinder Operated Valves1 Connect instrument quality air, preferably through an air filter/regulator of adequate size The recommended air pres-

sure is 80-120 psi (5-8 bar) Refer to the appropriate bulletin/drawing for port and cylinder size details 2 Ensure the supply air is free from moisture, dirt, and other foreign particles Drain the filter regulator before operating

the actuator so that pipe rust and dirt if any in the air line will be removed before actuation 3 If valves are supplied with electrical accessories like limit switch and solenoid valve, ensure wiring is done as per local

electrical safety codes and regulations Ensure correct electrical supply is given to electrical accessories for proper func-tioning and safety of the equipment

4 Open the valve by energizing the solenoid valve/giving air supply to cylinder and operate the valve 2-3 times

Manual valvesOpen/Close the valve manually and observe valve operation

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MAINTENANCE

NOTICE

Any modification or use of unauthorized parts voids any and all warranty considerations

LubricationThe manual valve stem should be lubricated at regular intervals for smooth operation of the valve A lubrication nipple is provided on the collar Cylinder operated valves do not require routine lubrication

NOTICE

If the cylinder actuator is disassembled for repair, the cylinder wall and seals need to be lubricated with a lithium-based grease prior to reassembly

Manual Valve Stem Cylinder Actuator

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Packing Replacement

Relieve line pressure before loosening gland nuts to avoid injury and/or equipment damage

1 Relieve the line pressure

2 Fully close the valve

3 Ensure the line is empty, and flush if necessary

Manual Valves1 Ensure the valve is fully closed

2 Disconnect the stem from the gate (6) by removing the clevis bolts & nuts (5)

3 Rotate the handwheel (1) counter-clockwise by holding the stem from rotation, so that the stem retracts fully from the gate

4 If valves are supplied with bellows, ensure stem is not rotating, as rotation will damage the bellows

5 Remove the gland nuts (2) and the gland (3)

6 Remove the old packing (4) from the packing chamber, one layer at a time, using a long thin tool to pry it out

7 Install the new packing (4), one at a time, to fit along each side of the gate The ends must be square cut Wrap the ends with TFE tape to prevent fraying The packing should be a perfect fit in the seal & gate area on both sides

8 Install the packing gland (3) and gland nuts (2)

9 Ensure the gap betweem the gland and the gate is uniform all around

10 Tighten the gland nuts finger tight plus one half turn

11 Lower the stem by rotating the handwheel clockwise while hold-ing the stem and fasten the stem to the gate with nuts & bolts (5)

Cylinder operated valves1 Switch off the electrical supply to the solenoid and limit switches

2 Remove the cylinder tubing and vent the air inside the cylinder

3 Disconnect the piston rod from the gate by removing the clevis bolts & nuts

4 Apply air slightly to the bottom port of the actuator so that the piston rod is retracted from the gate

5 Remove the actuator assembly from the valve by removing the fasteners connecting the yokes to the valve body

6 Remove the gland nuts (2) and the gland (3)

7 Remove the old packing (4) from the packing chamber, one layer at a time, using a long thin tool to pry it out

8 Install the new packing (4), one at a time, to fit along each side of the gate The ends must be square cut Wrap the ends with TFE tape to prevent fraying The packing should be a perfect fit in the seal & gate area on both sides

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9 Install the packing gland (3) and gland nuts (2)

10 Ensure the gap betweem the gland and the gate is uniform all around

11 Tighten the gland nuts finger tight plus one half turn

12 Mount the actuator assembly to the valve by attaching fasteners connecting the yokes to the valve body

NOTICEIf leakage is observed from the packing area after installing the valve in the pipeline and the valve is pressurized or charged with media, tighten the gland nuts evenly side to side just enough to stop leakage Do not over-tighten the gland nuts

Seal Replacement

Relieve line pressure before attempting to remove the valve from the line to avoid personnel injury and/or equipment damage If the valve has a pneumatic actuator, solenoid valve, limit switches, or other accessories, disconnect electrical and pneumatic supply

Series 740

1 Relieve the line pressure and close the valve Flush the line if neces-sary

2 Remove the valve from the line by loosening the flange mounting bolts, studs, and nuts

3 Clamp the valve in the vertical position to a fixture Do not block the valve port when clamping the valve An overhead hoist may be needed for larger size valves

4 Disconnect the stem from the gate by removing the clevis, bolts, and nuts (1)

5 Remove the actuator and superstructure from the valve

6 Remove the gland nuts (2), gland (3), and gland packing (4) from the valve

7 Remove the gate (5) carefully from the valve body Clean the gate and smooth out any rough surfaces

8 Remove the seal (6) by pulling it out of the top of the valve body

9 Clean and inspect the body (7) for any damage, particularly sharp edges that may cut the seal Smooth out if necessary

10 Saturate the body seal groove area with a good water–soluble lubri-cant that will not affect the seal or process

11 Inspect the new seal (6) and saturate both ends of the seal

12 Insert one end of the seal from the top side Reach into the port area and pull the seal through the groove of the port area and pull the seal from the top of the body Ensure the seal is not overstretched

13 Install the gate (5) and mount the actuator or handwheel

14 Operate the gate to seat the seal into the bottom groove and cycle several

Valve Size Maximum Length

Up to 8” 20 mm

10” - 16” 25 mm

18” and Up 30 mm

Table 1

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times With the seal forced fully into the seal groove, cut each end of the seal off to the required extended length Refer to Table 1

15 While leaving the gate in the closed position, retract the actuator to the open position

16 Install the PTFE wiiper and repack the valve

17 Adjust the packing for tight shutoff when the valve is installed and pres-surized to operating pressure

Series 752/755/755P/755R

1 Relieve the line pressure and close the valve Flush the line if necessary

2 Remove the valve from the line by loosening the flange mounting bolts, studs, and nuts

3 Clamp the valve in the vertical position to a fixture Do not block the valve port when clamping the valve An overhead hoist may be needed for larger size valves

4 Disconnect the stem from the gate by removing the clevis bolts and nuts (1)

5 Remove the actuator and superstructure from the valve

6 Remove the gland nut (2) and gland (3) , and glandpacking (4) from the valve

7 Remove the gate (5) carefully from the valve body Clean the gate and smooth out any rough surfaces

8 Place the valve in a horizontal position and remove the valve body fas-teners

9 Split the valve body assembly

10 Remove the U-seal (6)

11 Clean and inspect the new U-seal

12 Inspect the bore liner (8) and insert it into the body as shown (Applicable for Series 755)

13 Place the U-seal onto the slot provided and ensure 2mm clearance is avail-able before inserting the gate above the pocket as shown at right

14 Slide the gate as shown below and place the second body over the first body and loosely tighten the bolts and nuts

15 Flip the body to vertical position and press the gate downwards towards the U-seal and tighten the fasteners to the torques listed in Table 2

16 Repack the valve

Series 755 Bore Liner

8

2 mm

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17 Adjust the packing for tight shutoff when the valve is installed and pressurized to operating pressure

ACTUATOR MAINTENANCE

Pneumatic CylinderThe Bray/VAAS pneumatic cylinder actuator is a low maintenance design and does not require routine maintenance It has an FRP tube which is lubricated for life with a special coating on the inside wall Filtered dry, instrument quality air (non-lubricated) should be used for its operation at the specified air supply pressure

Recommended Spare PartsFollowing are parts recommended as spares, which may be stocked Following are general recommended spares for valves Provide the valve serial number and work order number from the nameplate for proper parts

• Gland packing

• Spare Seal

• Cylinder repair kit

PACKING DETAILSSeries 740

Valve size (in ) Packing Size (mm) Length, mm No of layers

2 Sq 8 75 3

3 Sq 10 110 3

4 Sq 10 130 3

5 Sq 10 180 3

6 Sq 10 200 3

8 Sq 10 235 3

10 Sq 10 300 3

12 Sq 10 350 3

14 Sq 12 7 400 3

16 Sq 12 7 450 3

18 Sq 16 500 3

20 Sq 16 550 4

24 Sq 16 650 4

Bolt Size

(mm)

Torque

N-m ft -lb

M8 15 11

M10 30 22

M12 55 41

M16 130 96

M20 255 188

M24 440 325

M30 875 645

M36 1530 1128

M42 2445 1803

Table 2

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Series 752/755/755P/755R (CWP-10 & 16)

Valve size (in ) Packing Size (mm)Length (mm)

Packing Layer

Quad Seal Layer

Total Layers

2 Sq 8 180 2 1 3

3 Sq 10 245 2 1 3

4 Sq 10 320 2 1 3

5 Sq 10 395 2 1 3

6 Sq 10 490 2 1 3

8 Sq 10 580 2 1 3

10 Sq 10 675 2 1 3

12 Sq 12 7 975 2 1 3

14 Sq 12 7 975 2 1 3

16 Sq 16 990 2 1 3

18 Sq 16 1120 3 1 4

20 Sq 16 1200 3 1 4

24 Sq 16 1440 3 1 4

Series 752/755/755P/755R (CWP-20)

Valve size (in ) Packing Size (mm)Length (mm)

Packing Layer

Quad Seal Layer

Total Layers

2 Sq 8 180 2 1 3

3 Sq 10 245 2 1 3

4 Sq 10 320 2 1 3

5 Sq 10 395 2 1 3

6 Sq 10 490 2 1 3

8 Sq 10 580 2 1 3

10 Sq 12 7 700 2 1 3

12 Sq 16 800 2 1 3

14 Sq 16 900 2 1 3

16 Sq 16 1050 2 1 3

18 Sq 19 1120 3 1 4

20 Sq 19 1200 3 1 4

24 Sq 19 1440 3 1 4

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All statements, technical information, and recommendations in this bulletin are for general use only Consult Bray/VAAS representatives or factory for the specific requirements and material selection for your intended application The right to change or modify product design or product without prior notice is reserved Patents issued and applied for worldwide

Bray® is a registered trademark ofBray International, Inc © 2015 Bray International, Inc All rights reserved

OM_Biderectional - Perimeter Seat Series_12_20_2016

Bray/VAASDivision of Bray International, Inc 13333 Westland East Blvd Houston, Texas 77041Tel: 281 894 5454 • www bray com

Troubleshooting

Trouble Possible cause Solution

Media oozing out of gland packing Packing deteriorated Replace packing

In fully closed position, valve leaks

Seat is worn out or torn Replace seat

Gate is scratched Replace gate

High torque during valve seating and unseating

Misalignment between gate and stem

a) Remove the clevis fastenersb) Loosen the superstructure fastenersc) Adjust the alignment of the stem and

gated) Connect the clevis fastenerse) Retighten superstructure fasteners

Packing is not tighten properly Adjust gland nuts

Valve jerks during open and close

Superstructure fasteners loosen Tighten the super structure fasteners

Insufficient air supplyPneumatic operated valves: Increase supply pressure

Solenoid valve dust accumulation Remove and clean solenoid valve

Piston rod seal damaged Replace seal

bray/ vaas bidirectional - industrial valves | control valves & … knife gate... · 2017. 8....

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