Emerson Anderson greenwood marvac 121 series User manual

ANDERSON GREENWOOD MARVAC FIGURE 121 PRESSURE AND VACUUM RELIEF VALVE

INSTALLATION AND MAINTENANCE INSTRUCTIONS

SAFETY PRECAUTIONS

Read and understand this instruction manual

before installing, operating or performing

maintenance on Figure 121 pressure and

vacuum relief valves. Follow all precautions

and warnings noted herein when installing,

operating or performing maintenance on this

equipment.

NOTE

This manual is issued for guidance only and does not

affect our standard terms and conditions and our

product limited warranty, all of which are available on

request.

Read Anderson Greenwood Marvac general instructions before continuing

1 INSTALLATION

Figure 121 pressure and vacuum relief valves

must be mated with the appropriate flange.

1. These valves must be gasketed and bolted

to a flat machined horizontal flange. Bolts

must be tightened uniformly to ensure a

good seal.

2. This valve does not contain any internal

packing. Therefore, internal checks should

not be necessary.

3. It is recommended that carbon steel valves

be given a coat of paint immediately after

installation is complete. Apply paint to

external surfaces only.

2 MAINTENANCE

(during atmospheric venting period)

WARNING

The relief valve must be isolated from tank

pressure before servicing. All gas must be

blocked and pressure vented safely. Wear

appropriate gloves and/or breathing apparatus if

hazardous vapors are present.

Refer to Figure 1

1. Remove weather hood (item 3) and vacuum

cover (item 7), inspect O-ring in vacuum

cover for damage and replace if necessary.

2. Remove pallet assembly to inspect pallet

seating for wear and replace if necessary.

3. To replace damaged/worn items from pallet

assembly (see recommended spares):

a. remove nut from pallet stem, remove

support disc, diaphragm and backing disc

b. clean pallet surface and threads

c. replace with new parts

d. reassemble in reverse order

4. Inspect valve seat (item 2) for wear and

regrind or replace where necessary.

5. Clean seating surface thoroughly with

suitable solvent and apply a thin smear of

light spindle oil.

6. Generally clean the inside of the valve,

remove all foreign matter and repaint

exterior where possible to prevent

corrosion.

7. Replace pressure pallet on pressure seat

and vacuum pallet (with lead disc if fitted).

8. Replace weather hood, secure with hand

nuts.

9. Replace vacuum cover and replace sealing

washers if necessary, secure with screws.

NOTE

The efficiency of the valve depends on maintaining

good seating surfaces. Therefore, maintenance

periods should be adjusted to suit service conditions.

ANDERSON GREENWOOD MARVAC FIGURE 121 PRESSURE AND VACUUM RELIEF VALVE

INSTALLATION AND MAINTENANCE INSTRUCTIONS

3 RECOMMENDED SPARES

1. Item 10 Nitrile o-ring

2. Item 9 Sealing washers

3. Item 14 Spacer disc (non-asbestos fiber)

4. Item 15 Diaphragm backing disc

(non-asbestos fiber)

5. Item 16 Diaphragm (PTFE)

PARTS LIST

Item Description Alum spec. C.steel SS spec

1Valve body Aluminum W.C.B. 316 SS

2Removable seat Aluminum 316 SS 316 SS

3Weather hood Aluminum C.Steel 316 SS

4Handle nuts Phenolic Phenolic Phenolic

5Screen ring Aluminum C.Steel 316 SS

6Screen Galv St Galv St 18/8 SS

7Cover Aluminum W.C.B. 316 SS

8Cover screws ZP Steel ZP Steel 18/8 SS

9Sealing washers G Fiber G Fiber G Fiber

10 O-ring seal Nitrile Nitrile Nitrile

11 Pallet 316 SS 316 SS 316 SS

12 Pallet stem 316 SS 316 SS 316 SS

13 Pallet guide posts 316 SS 316 SS 316 SS

14 Spacer disc Non-asbestos Non-asbestos Non-asbestos

15 Diaphragm back.disc Non-asbestos Non-asbestos Non-asbestos

16 Diaphragm PTFE PTFE PTFE

17 Diaphragm supp.disc 316 SS 316 SS 316 SS

Neither Emerson, Emerson Automation Solutions, nor any of their affiliated entities assumes responsibility for the selection, use or maintenance of any product.

Responsibility for proper selection, use, and maintenance of any product remains solely with the purchaser and end user.

Anderson Greenwood is a mark owned by one of the companies in the Emerson Automation Solutions business unit of Emerson Electric Co. Emerson Automation

Solutions, Emerson and the Emerson logo are trademarks and service marks of Emerson Electric Co. All other marks are the property of their respective owners.

The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not to be

construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. All sales are governed by

our terms and conditions, which are available upon request. We reserve the right to modify or improve the designs or specifications of such products at any time without

notice.

Emerson.com/FinalControl

FIGURE 1

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