Fisher 912, 912H Installation Guide Manuals & Guides

Installation Guide
D100317X014

English – June 2010

912N Series

Introduction

This installation guide provides instructions for installation, startup
and adjustment. To receive a copy of the instruction manual, contact
your local Sales Office or view a copy at www.fisher.com. For further
information, refer to: 912N Series Instruction Manual, D100317X012.

PED Category

This product may be used as a pressure accessory with pressure
equipment in the following Pressure Equipment Directive categories.
It may also be used outside of the Pressure Equipment Directive
using sound engineering practice (SEP) per table below. For
information on the current PED revision, see Bulletin: D103053X012.

PRODUCT SIZE CATEGORIES FLUID TYPE

1/4 and 3/8 NPT SEP 1

Specifications

Body Sizes and End Connection Styles

Inlet: 1/4 NPT
Outlet: 1/4 or 3/8 NPT

Maximum Allowable Inlet Pressure

(1)

17.2 bar / 250 psig

Outlet Pressure Ranges

(1)

See Table 1

Maximum Allowable Outlet Pressure

(1)

Emergency Outlet Pressure: 1.4 bar / 20 psig
Recommended Outlet Pressure to Avoid Internal Part
Damage: 0.21 bar d / 3 psid above outlet pressure setting;

provide external relief if start-to-discharge point exceeds

0.21 bar d / 3 psid

Proof Test Pressure

All Pressure Retaining Components have been proof tested
per Directive.

Temperature Capabilities

(1)

-29 to 71°C / -20 to 160°F

Installation

WARNING

!

Only qualified personnel should install or service
regulator. Regulators should be installed,
operated and maintained in accordance with
international and applicable codes and regulations
and Emerson Process Management Regulator
Technologies, Inc. instructions.

If the regulator vents fluid or a leak develops in
the system, it indicates that service is required.
Failure to take the regulator out of service
immediately may create a hazardous condition.

Personal injury, equipment damage, or leakage
due to escaping fluid or bursting of pressure­containing parts may result if this regulator
is overpressured or is installed where service
conditions could exceed the limits given in the
Specifications section, or where conditions
exceed any ratings of the adjacent piping or
piping connections.

Table 1. Outlet Pressure Ranges

APPROXIMATE POINT ABOVE

AVAILABLE

CONFIGURATION

912N Series

912N Series

with handwheel

1. Internal Relief Performance is only adequate for relieving minor build-up situations.
External relief is required if start-to-discharge point exceeds 0.21 bar d / 3 psid.

OUTLET PRESSURE RANGE

mbar In. w.c. mbar In. w.c.

7 to 17
12 to 25
23 to 32
30 to 60

0.03 to 0.18 bar

0.18 to 0.34 bar

20 to 60

0.18 to 0.34 bar

3 to 7

5 to 10

9.25 to 13
12 to 24

0.5 to 2.7 psig

2.7 to 5 psig

8 to 24

2.7 to 5 psig

OUTLET PRESSURE SETTING

AT WHICH INTERNAL RELIEF

STARTS TO DISCHARGE

12 to 52
20 to 75
40 to 97

40 to 210

0.05 to 0.47 bar

0.26 to 0.86 bar

75 to 88

0.37 to 0.46 bar

17 to 3 psig

(1)

0.7 to 6.8 psig

(1)

3.8 to 12.5 psig

30.3 to 35.4

(1)

5.4 to 6.7 psig

5 to 21
8 to 30

16 to 39

(1)

To avoid such injury or damage, provide pressure­relieving or pressure-limiting devices (as required
by the appropriate code, regulation or standard) to
prevent service conditions from exceeding limits.

Additionally, physical damage to the regulator
could result in personal injury and property
damage due to escaping fluid. To avoid such injury
and damage, install the backpressure regulator in
a safe location.

Clean out all pipelines before installation of the regulator and check
to be sure the regulator has not been damaged or has collected
foreign material during shipping. For NPT bodies, apply pipe
compound to the external pipe threads. For flanged bodies, use
suitable line gaskets and approved piping and bolting practices.
Install the regulator in any position desired, unless otherwise
specified, but be sure flow through the body is in the direction
indicated by the arrow on the body.

Note

It is important that the backpressure regulator
be installed so that the vent hole in the spring
case is unobstructed at all times. For outdoor
installations, the backpressure regulator should be
located away from vehicular traffic and positioned
so that water, ice, and other foreign materials
cannot enter the spring case through the vent.
Avoid placing the backpressure regulator beneath
eaves or downspouts, and be sure it is above the
probable snow level.

Overpressure Protection

The recommended pressure limitations are stamped on the
regulator nameplate. Some type of overpressure protection
is needed if the actual inlet pressure exceeds the maximum
operating outlet pressure rating. Overpressure protection should
also be provided if the regulator inlet pressure is greater than the
safe working pressure of the downstream equipment.

Regulator operation below the maximum pressure limitations
does not preclude the possibility of damage from external
sources or debris in the line. The regulator should be inspected
for damage after any overpressure condition.

(1)

(1)

1. The pressure/temperature limits in this installation guide and any applicable standard
or code limitation should not be exceeded.

912N Series

Startup

The regulator is factory set at approximately the midpoint of the
spring range or the pressure requested, so an initial adjustment
may be required to give the desired results. With proper installation
completed and relief valves properly adjusted, slowly open the
upstream and downstream shutoff valves.

Adjustment

To change the outlet pressure, remove closing cap or loosen the
locknut and turn the adjusting screw clockwise to increase outlet
pressure or counterclockwise to decrease pressure. Monitor the
outlet pressure with a test gauge during the adjustment. Replace
closing cap or tighten the locknut to maintain the desired setting.

Taking Out of Service (Shutdown)

WARNING

!

To avoid personal injury resulting from sudden
release of pressure, isolate the regulator from all
pressure before attempting disassembly.

Parts List

Key Description

1 Regulator Body
2 Spring Case
3 Closing Cap
4 Adjusting Screw
5 Regulator Spring
6 Relief Valve Spring
7 Spring Seat
8 Pin
9 Relief Valve Seat
10 Diaphragm Plate
11 Disk Holder
12 Fulcrum Rod
13 Machine Screw

*Recommended spare part

Key Description

14 Machine Screw
15 Diaphragm
16 Vent Screen
17* Closing Cap Gasket
18 Closing Spring, for 912N Series

with handwheel only

19 Spacer Ring, for 912N Series

with handwheel only

20 Lockwheel, for 912N Series

with handwheel only

25 Spring Seat, for 912N Series

with handwheel only

29* Disk

1/8 NPT

BB7822

3

4

2

7

6

16

15

29

12

91

11

17

8

24

5

10

13

FOR TYPE 912H
ONLY (LOCATE
PER T10895)

14

Figure 1. 912N Series Pressure Regulator Assembly

4

20

3

19

2

7

6

14

15

BC2347

1/8 NPT

25

8

5

10

13

16

29

19111218

Figure 2. 912N Series with Handwheel Construction Assembly

[e-mail]

Fisher.com

Emerson Automation Solutions

Americas
McKinney, Texas 75070 USA
T [phone]

[phone]

Europe
Bologna 40013, Italy
T [phone]

For further information on the current
PED revision see Bulletin: D103053X012
or scan the QR code.

Facebook.com/EmersonAutomationSolutions

LinkedIn.com/company/emerson-automation-solutions

Twitter.com/emr_automation

Asia Pacic

Singapore 128461, Singapore
T [phone]

Middle East and Africa

Dubai, United Arab Emirates
T [phone]

D100317X014 © 2002, 2019 Emerson Process Management Regulator
Technologies, Inc. All rights reserved. 04/19.
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