Emerson VAREC Series, 2020B, 3500B, 2010B, Varec 2010B Series Instruction, Operation And Maintenance Manual

VAREC SERIES 2010B/2020B/3500B PRESSURE AND VACUUM RELIEF VALVE

INSTRUCTION, OPERATION AND MAINTENANCE MANUAL

Before installation these instructions must be fully read and understood

2010B

2020B

3500B

DISCLAIMER OF WARRANTIES

The contract between VAREC Vapor ControlInc.
and our customer states VAREC’s entire
obligation. The contents of this instruction
manual shall not become part of or modify
any prior or existing agreement, commitment
or relationship between VAREC Vapor Control
Inc. and our customer. There are no express
or implied warranties set out in this instruction
manual. The only warranties that apply are
those in the existing contract between VAREC
Vapor Control Inc. and our customer.

The VAREC Vapor Control Inc.
2010B/2020B/3500B Series pressure and/or
vacuum relief valves have not been tested by
VAREC Vapor Control Inc. under all possible
operational conditions, and VAREC Vapor
Control Inc. does not have all the data relative
to your application. The information in this
instruction manual is not all inclusive and
does not and cannot take into account all
unique situations. Consequently, you should
review this product literature in view of your
application. Ifyou have any further questions,
please contact VAREC Vapor Control Inc. for
assistance.

LIMITATIONS OF SELLER’S LIABILITY

If it is determined that this instruction manual
created some new warranties, VAREC Vapor
Control Inc. liability shall be limited to repair
or replacement under the standard warranty
clause. In no case shall VAREC Vapor Control
Inc. liability exceed that stated as limitations of
remedy in the contract between VAREC Vapor
Control Inc. and our customer

33-11516 Rev. E

Emerson.com/FinalControl © 2017 Emerson. All rights reserved. VCIOM-03769-EN 18/08

VAREC SERIES 2010B/2020B/3500B PRESSURE AND VACUUM RELIEF VALVE

INSTRUCTION, OPERATION AND MAINTENANCE MANUAL

SAFETY PRECAUTIONS

Read and understand this instruction manual
before installing, operating or performing
maintenance on Varec Vapor Control Inc.
2010B/2020B/3500B series pressure and/or
vacuum relief valve. Follow all precautions
and warnings noted herein when installing,
operating or performing maintenance on this
equipment.

WARNING

Relief valve must be isolated from tank pressure
before servicing. All gas must be blocked and
pressure safely vented.

SAFETY PRECAUTION DEFINITIONS

CAUTION

Damage to equipment may result if this
precaution is disregarded.

WARNING

Direct injury to personnel or damage to
equipment which can cause injury to personnel
may result if this precaution is not followed.

GENERAL INFORMATION

The 2010B/2020B/3500B Series pressure
and/or vacuum relief valves are designed to
protect low pressure storage tanks, sludge
digesters and gas holders from excessive
pressure and/or vacuum. The valve is installed
on the storage tank roof or digester cover.
It may be used in combination with a VAREC
Vapor Control Inc. flame arrester.
The 2010B Series valve relieves pressure
directly to the atmosphere. A weatherhood and
mesh screen protect the pressure pallet and
guideposts. Vacuum pressure is relieved by
inbreathing ambient air.
The 2020B Series valve relieves pressure
through an enclosed outlet adapter. Product
vapors may be piped away rather than relieving
directly to the atmosphere. Vacuum pressure is
relieved by inbreathing ambient air.
The 3500B Series valve is a vacuum relief valve
that relieves negative pressure by inbreathing
ambient air.

CONSTRUCTION

Standard materials of construction include
cast body and cover(s). Pallets are dead weight
loaded with lead or coated steel weights and
include a flexible membrane sealing insert.
The pallet is loosely guided through a center
stem and pallet guide posts.
The “All-Weather” Models 2011B, 2021B and
3501B Series include a special coating on
portions of the pallets, seat rings and guides to
eliminate ice accumulation.

OPERATION

When the internal tank pressure approaches
the valve setting, the pressure pallet begins to
lift. As the pressure exceeds the valve setting,
the pressure pallet lifts off the seat ring.
Excess product vapor is allowed to vent to the
atmosphere or through the pipe away system
adapter, relieving the over pressure condition.
The pallet automatically re-seats as the tank
pressure drops below the valve setting.
If a vacuum within the tank approaches the
valve setting, the vacuum pallet begins to
lift. As the vacuum exceeds the valve setting,
the vacuum pallet lifts off the seat ring.
Atmospheric air is allowed to flow into the
tank, relieving the excess vacuum condition.
The pallet automatically re-seats as the
vacuum drops below the valve setting.

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VAREC SERIES 2010B/2020B/3500B PRESSURE AND VACUUM RELIEF VALVE

INSTRUCTION, OPERATION AND MAINTENANCE MANUAL

INSTALLATION

2010B/2020B/3500B Series pressure and
vacuum relief valves must be mated with the
appropriate flange(s). The nozzle must be
plumb and the inlet flange face level to ensure
proper operation of the relief valve.

1. Remove the valve from the shipping
container. Check to see if extra loading
weights were bagged and packed
separately.

2. Remove the weatherhood and/or cover(s)
and all packing material above the pallets
and within the valve.

CAUTION

Whenever the weatherhood and/or cover(s)
is removed and reinstalled, the end of the
pallet stem must engage the stem guide in the
weatherhood and/or the stem guide chamber
in the cover(s) for proper seating and valve
operation.

Note: spun sheet metal pallets have a
compensating weight on top of the pallet.
Donot remove this weight. Refer to Table 1
forincremental weight information.

3. To load vacuum pallet weights, perform the
following:

a. With vacuum cover and gasket removed,

remove vacuum pallet assembly

frombody.
b. Remove grip ring from pallet stem.
c. Non-variable setting: locate weight

marked “VACUUM” and place on top

of compensating weight and/or pallet.

Secure with grip ring.
Note: if setting is less than 2” WC,

weightwill be pre-loaded on the pallet.
d. Variable setting: each lead weight

is calibrated from 1” WC increment.

(Increments of ¼” WC and ½” WC may

be supplied on special order). Those

weights necessary for the initial specified

setting will be tagged separately from

any extra weight provided. Remove the

packaging on the weights tagged from

the initial specified setting and place

the weights on top of the compensating

weight. Secure with grip ring. Store

remaining weights for future use (in case

the setting needs to be increased).
e. Weigh entire pallet assembly (including

installed weights). Using Table 1, confirm

that the assembly is the proper weight to

achieve the required setting. Allowable

weight tolerance is +5%,-5%.
f. Remove any remaining packing material

from valve body. Wipe vacuum seat ring,

guide posts and pallet assembly with a

soft cloth to remove any material which

could affect valve operation.

g. Place pallet assembly on valve body seat.

Ensure that pallet moves freely within
guide posts and rests flat on the seat
ring.

h. Replace the cover gasket and cover.

Tighten cover screws uniformly.

CAUTION

The end of the pallet stem must engage the stem
guide chamber in the cover for proper seating and
valve operation.

Note: spun sheet metal pallets have a
compensating weight on top of the pallet.
Donot remove this weight. Refer to Table 1
forincremental weight information.

4. To load pressure pallet weights, perform the
following:

a. With weatherhood from Model 2010B, or

pipe away adapter cover and gasket from
Model 2020B removed, remove pressure

pallet assembly from body.
b. Remove grip ring from pallet stem.
c. Non-variable setting: locate weight

marked “PRESSURE” and place on top

of compensating weight and/or pallet.

Secure with grip ring. If setting is less

than 2” WC, weight will be pre-loaded

onthe pallet.
d. Variable setting: each lead weight

is calibrated from 1” WC increment.

(Increments of ¼” WC and ½” WC may

be supplied on special order). Those

weights necessary for the initial specified

setting will be tagged separately from

any extra weight provided. Remove the

packaging on the weights tagged from

the initial specified setting and place

the weights on top of the compensating

weight. Secure with grip ring. Store

remaining weights for future use (in case

the setting needs to be increased).
e. Weigh entire pallet assembly (including

installed weights). Using Table 1, confirm

that the assembly is the proper weight to

achieve the required setting. Allowable

weight tolerance is +5%,-5%.
f. Remove any remaining packing material

from valve body. Wipe pressure seat ring,

guide posts and pallet assembly with a

soft cloth to remove any material which

could affect valve operation.
g. Place pallet assembly on seat. Ensure

that pallet moves freely within guide

posts and rests flat on the seat ring.
h. Replace the weatherhood on

Model2010B or the pressure cover and

gasket on Model 2020B. Tighten all nuts

and screws uniformly.

3

VAREC SERIES 2010B/2020B/3500B PRESSURE AND VACUUM RELIEF VALVE

INSTRUCTION, OPERATION AND MAINTENANCE MANUAL

CAUTION

The end of the pallet stem must engage the
stem guide in the weatherhood or the stem guide
chamber in the cover for proper seating and valve
operation.

5. Place the valve in a level position. Reach up
through the inlet flange and carefully push
up on the pressure pallet, then lower it onto
the seat. Pallet should move up and down
freely and rest flat on the seat ring.

6. Check the vacuum pallet by using a non­sparking tool which will pass through the
center of the mesh screen. Push up on the
vacuum pallet, then lower it onto the seat.
Pallet should move freely and rest flat on
the seat ring.

7. Mount the valve on the flanged nozzle or
flame arrester using the appropriate full
faced gasket.

CAUTION

Do not mate a flat face flange to a raised face
flange.
If it necessary to mate an ANSI Class 125 F.F.
Flange with an ANSI Class 150 R.F. Flange, use
the proper spacer to convert the raised face to
aflat face.

8. Verify that the valve is level to permit proper
operation of the pallets. Install mounting
hardware, and tighten uniformly.

9. When using Model 2020B Series, install
connecting piping (if required) to outlet
flange. Use a full faced gasket and tighten
all mounting hardware uniformly.

Note: it is recommended that steel and iron
valves be given a coat of paint immediately
after installation is completed. Apply paint
toexternal surfaces only.

MAINTENANCE

The valve should be inspected and cleaned
at periodic intervals. The first inspection
should be made approximately 30 days after
commissioning. Subsequent inspections should
be made every 30 days. The user may adjust the
schedule for his own convenience and safety,
depending upon the product being stored.

WARNING

• Relief valve must be isolated from tank pressure

before servicing. All gas must be blocked and
pressure safely vented. If no isolation valve
is present, carefully open vacuum cover or
lift pressure pallet, allowing pressure to vent
slowly.

• Wear appropriate gloves and/or breathing

apparatus if hazardous vapors are present.

1. To inspect valve proceed as follows:
a. Remove the weatherhood and/or

cover(s).

b. Remove pallets one at a time. Identify the

pallets to ensure they are returned tothe
correct valve seat.

c. Inspect pallet inserts for ripples, tears,

or nicks, as well as seating surfaces for
debris, abrasion or pitting. Pallet edges
and guide posts should be free or burrs,
corrosion or other obvious damage.
Clean all components, replacing any
showing excess wear or damage. On the
“All-Weather” versions, inspect the PTFE
coating for any damage that wouldaffect
operation.

d. Reassemble in reverse order.

CAUTION

The end of the pallet stem must engage the stem
guide in the weatherhood and/or the stem guide
chamber in the cover(s) for proper seating and
valve operation.

CAUTION

During periods of freezing weather, extra
maintenance is required for Models
2010B/2020B/3500B. Either remove the pallets or
apply generous portions of silicone grease to the
pallets, seat rings and guide posts. When using
silicone grease, inspect valves at least weekly.
This procedure is not required for “All-Weather”
Models 2011B, 2021B or 3501B.

2. To replace pallet insert proceed as follows:
a. Remove weatherhood and/or cover(s)

and then pallet assembly.

b. Remove nut from base of pallet stem.

Remove retainer plate and insert.
Clean all surfaces and threads. Install
new insert, handling carefully to avoid
damaging insert or pallet.

c. Reassemble pallet and place on seat

of valve body. Ensure pallet assembly
moves freely within guide posts and
rests flat on seat ring.

d. Reinstall weatherhood and/or cover(s).

CAUTION

The end of the pallet stem must engage the stem
guide in the weatherhood and/or the stem guide
chamber in the cover(s) for proper seating and
valve operation.

4

VAREC SERIES 2010B/2020B/3500B PRESSURE AND VACUUM RELIEF VALVE

INSTRUCTION, OPERATION AND MAINTENANCE MANUAL

3. To replace pressure seat ring perform the
following:

a For Model 2010B, remove weatherhood,

screen, spacer ring, pallet assembly and
guide posts. For Model 2020B, remove
pressure cover, spacer (high setting),
gaskets, pallet assembly, outlet adapter,
and guide posts.

b. Remove seat ring and O-Ring from valve

body. Clean body, outlet adapter mating
surfaces and O-Ring Groove.

c. Install new O-Ring into groove; insure

that the O-Ring stays properly in groove
while installing seat ring.

d. Install new seat ring carefully to avoid

distortion. Reassemble guide posts
(2010B) or outlet adapter (2020B) to
secure seat. Ensure that seat is flush

and level with valve body.
e. Reassemble guide posts (2020B).
f. Place pallet assembly on valve body

seat.Ensure pallet assembly moves

freely within guide posts and rest flat

onseat ring.
g. Reassemble remaining parts in reverse

order.

CAUTION

The end of the pallet stem must engage the stem
guide in the weatherhood and/or the stem guide
chamber in the cover(s) for proper seating and
valve operation.

4. To replace vacuum seat ring perform the

following:

a. Remove vacuum cover, spacer (high

setting), gaskets, pallet assembly,

screen retainer, screen and guide posts.
b. Remove seat ring and O-Ring from valve

body. Clean body mating surface and

O-Ring groove.

c. Install new O-Ring into groove; insure

that the O-Ring stays properly in groove
while installing seat ring.

d. Install new seat ring carefully to avoid

distortion. Reassemble screen and
retaining ring to secure seat ring.
Ensurethat seat is flush and level with

valve body.
e. Reassemble guide posts.
f. Place pallet assembly on valve body seat.

Ensure pallet assembly moves freely

within guide posts and rests flat on seat

ring.
g. Reassemble spacer, cover and gaskets.

CAUTION

The end of the pallet stem must engage the stem
guide chamber in the cover for proper seating and
valve operation.

5. Seat ring repair:
a. Seat may be ground or ground and

lapped (in place) to improve seal. Use a

lapping plate and medium valve grinding

compound, applying light pressure.
b. Finish lapping with a fine compound.

Avoid scoring or removing excessive

amounts of material.
c. Clean all compound from valve parts.
d. Hand buff seat with a medium grade

`Scotch-Brite’ (#7447) pad and light oil.

CAUTION

Whenever the weatherhood and/or cover(s)
is removed and reinstalled, the end of the
pallet stem must engage the stem guide in the
weatherhood and/or the stem guide chamber
in the cover(s) for proper seating and valve
operation.

CALIBRATION

To verify setting, calculate the total necessary weight using the table below. Check this value
against the actual weight of the pallet assembly (including loading weights). Adjust loading
weights as required.

PALLET LOADING (INCLUDES WEIGHT OF PALLET)

Valve
size

2” 8.3 4.8
3” 16.8 9.7
4” 22.1 12.8
6” 43.4 25.1
8” 72.7 42.0
10” 120.1 69.4

12” 179.9 104.0
Weight tolerance: + 5%/- 5%
Setting tolerance: + 0%/- 10%

Ounces of weight required

perounce of setting

Ounces of weight required

perinch of WC setting

5