Emerson 1805 Instruction Manual

Instruction Manual
Form 1211

October 2011

1805 Series Relief Valves

WARNING

!

Failure to follow these instructions or
to properly install and maintain this
equipment could result in an explosion

and/or re causing property damage and

personal injury or death.

Fisher® relief valves must be installed,
operated and maintained in accordance
with federal, state, and local codes, rules

and regulations, and Emerson Process
Management Regulator Technologies,

Inc. instructions.

If a leak develops or if the outlet

continually vents gas, service to the unit

may be required.

1805 Series

Failure to correct trouble could result in

a hazardous condition. Only a qualied

person must install or service the unit.

Call a gas service person to service the
unit. Only a qualied person must install

or service the 1805 Series Relief Valves.

Introduction

Scope of the Manual

This Instruction Manual provides installation,
adjustment, maintenance, and parts ordering
information for 1805 Series relief valves.

Description

The 1805 Series relief valves are primarily designed
for use in farm tap applications where a safety relief

valve is needed between the rst and second stage

regulators. The 1805 Series is suitable for service on

P1026

Figure 1. 1805 Series Relief Valve

natural gas, air, propane, or any operating medium that
is not corrosive to the internal parts. Relief pressure
ranges from 5 to 125 psi / 0,34 to 8,6 bar. Maximum
pressure, including buildup, is 150 psi / 10,3 bar.

Specications

The Specications section lists the specications for

the 1805 Series relief valve. The following information
is stamped on the relief valve at the factory: type
number, date of manufacture, spring range, maximum
inlet pressure, and maximum allowable inlet pressure.

www.sherregulators.com

D100345X012

1805 Series

Specications

Available Constructions

Type 1805-2 - Cast iron spring case, closing cap
with 1/4 NPT vent placed over the adjusting screw.
Available in 3/4 and 1 NPT body sizes.
Type 1805-3 - Cast iron spring case, closing cap
with 1/4 NPT vent placed over the adjusting screw.
Available in 1-1/2 and 2 NPT body sizes.

Body Sizes and End Connection Style

3/4, 1, 1-1/2, or 2 NPT

Maximum Inlet Pressure

150 psig / 10,3 bar including buildup

Relief Valve Set Pressure Ranges

See Table 1

Type 1805-4 - Cast iron spring case. Available in
3/4 and 1 NPT body sizes.
Type 1805-5 - Cast iron spring case.
Available in 1-1/2 and 2 NPT body sizes.
Type 1805-7 - Cast iron spring case, closing cap
with 1/4 NPT vent placed over the adjusting screw,
screen in outlet. Available in 3/4 and 1 NPT
body sizes.

Body Style

Flow and IEC Sizing Coefcients

See Table 2

Temperature Capabilities

-20° to 150°F / -29° to 66°C

Approximate Shipping Weights

3/4 to 1 NPT bodies: 5 pounds / 2 kg
1-1/2 to 2 NPT bodies: 13 pounds / 6 kg

Globe body

1. The pressure/temperature limits in this Instruction Manual or any applicable standard limitation should not be exceeded.

Table 1. Relief Set Pressure Ranges

(1)

(1)

BODY SIZE

3/4 or 1 NPT

1-1/2 or 2 NPT

RELIEF PRESSURE RANGE

SPRING PART NUMBER

psig bar Inches mm Inches mm

5 to 35

10 to 60

20 to 125

5 to 20

10 to 50

35 to 125

0,34 to 2,4
0,69 to 4,1

1,4 to 8,6

0,34 to 1,4
0,69 to 3,5

2,4 to 8,6

1B986027212
1B788327022
1B788427022

1D892327022
1D665927022
1E543627142

SPRING COLOR

CODE

Green

Silver

Blue

Red
Blue

Yellow

SPRING FREE LENGTH

2.25

2.13

1.94

2.94

2.50

2.31

Table 2. Flow and IEC Sizing Coefcients

BODY SIZE C

3/4 to 1 NPT

1-1/2 to 2 NPT 0.94 0.44

1

35 0.79

K

m

X

T

0.73 0.39

SPRING WIRE

DIAMETER

57,2
54,1
49,3

74,7
63,5
58,7

IEC SIZING COEFFICIENTS

0.12

0.14

0.18

0.17

0.22

0.28

F

D

F

0.89

3,05
3,56
4,57

4,32
5,59
7,11

L

2

MXXXX

Type XXXX

UPPER

Type XXXX

Month Year

Type XXXX

INLET PRESSURE
OUTLET PRESSURE
ATMOSPHERIC PRESSURE

SPRING
SEAT

1805 Series

A6671

INLET PRESSURE

OUTLET PRESSURE

ATMOSPHERIC PRESSURE

DIAPHRAGM
HEAD

UNION NUT

O-RING
HOLDER

O-RING WASHER

Figure 2. 1805 Series Operational Schematic

DIAPHRAGM

VALVE GUIDE
ORIFICE

O-RING

BODY

O-RING

Principle of Operation

See Figure 2. Relief valves respond to changes in
upstream pressure. If upstream pressure increases
and exceeds the relief valve setting, the valve will
open and allow gas to vent to the atmosphere. When
upstream pressure returns to normal level (below the
setting of the relief valve), the relief valve automatically
closes and normal system operation resumes.

In the 1805 Series relief valves, the upstream pressure
registers underneath the diaphragm. Gas reaches
the diaphragm through the space between the O-ring

holder and the valve guide orice in 3/4 and 1 NPT

bodies or through registration holes in the valve guide

orice in 1-1/2 and 2 NPT bodies. When the upstream

pressure increases beyond the spring setting, the force
on the diaphragm overcomes spring compression.
The O-ring holder moves upward, carrying the
O-ring away from the valve seat. This opens the

ow line, allows gas to ow to the atmosphere, and

relieves the overpressure condition. When upstream
pressure registered on the diaphragm decreases to
a level below that of the spring setting of the relief
valve, the spring force pushes the diaphragm plate
and O-ring holder toward the valve seat. Contact

between O-ring and valve seat prevents further ow

to atmosphere.

3

1805 Series

TYPE CS200IN
SET AT 8-inches w.c. / 20 mbar

TYPE 1805 SET AT 40 psi /
2,8 bar ROTATE PIPING SO
DISCHARGE FROM RELIEF
VALVE MISSES REGULATOR

TYPE R622 ASSEMBLY
OR 4 SET AT 25 psi / 1,7 bar

INLET PRESSURE UP TO
750 psi / 51,7 bar

TEST GAUGE CONNECTION
PLUGGED-OPTIONAL

HAND VALVE
OR PLUG COCK
OPTIONAL

Figure 3. Typical Farm Tap Installation

Installation

After unpacking, check the relief valve for shipping
damage. Remove pipe scale and other foreign
material from the connecting pipeline. Coat the male
pipe threads with a suitable pipe compound. The unit

can be installed in any position as long as the ow is in

the direction indicated by the arrow cast on the body.

Protect the outlet and vents from entrance of rain,
snow, or other foreign material that may plug them.

Outdoor installations should include a rain cap
over the vents and outlet if they point upward.
Periodically check the openings to ensure that they
are not plugged.

Protect the relief valve against damage from vehicles
or other external sources.

Vents

WARNING

!

Venting gas may accumulate and be

an explosion hazard under enclosed

conditions such as in pit or underground

installations. Install remote vent lines to

carry gas to a safe area.

If remote vent lines are necessary, use the Type 1805-2,

-3, or -7 which have 1/4 NPT vent connections in the
closing cap. Remove the screen, if one is present in
the outlet, and install remote vent lines in the outlet and
closing cap openings. Remote vent lines must have the
largest practical diameter as possible. The vent lines
should be as short as possible with a minimum number
of bends or elbows.

4

1805 Series

Overpressure

Relief pressure ratings are from 5 to 125 psi / 0,34
to 8,6 bar. The maximum inlet pressure, including
buildup, is 150 psi / 10,3 bar. System operation within
these limitations does not eliminate the possibility of
damage from external sources or from debris in the gas
line. The relief valve should be inspected for damage
regularly and after any overpressure condition.

Startup

Key numbers are shown in Figure 4. With proper
installation completed and system equipment properly
adjusted, close any vent valves, and slowly open the
upstream shut-off valve while using pressure gauges to
monitor pressure.

If set pressure adjustment is necessary, monitor the inlet
pressure with a gauge during the adjustment procedure.

Adjustment

The range of allowable pressure settings is stamped
on the spring case (Types 1805-2, -4, and -7) or on
the nameplate (Types 1805-3 and -5). If a pressure
setting beyond the indicated range is required,
substitute the appropriate spring. Be sure to label
the relief valve to indicate the new pressure range.
Always use a pressure gauge to monitor pressure
when making adjustments.

1. On Types 1805-2, -3, and -7 remove the closing
cap (key 17).

2. Loosen hex nut (key 15).

3. To increase the relief setting, turn the adjusting
screw (key 14) clockwise. To decrease the relief
setting, turn the adjusting screw counterclockwise.

4. Tighten the hex nut.

Shutdown

Due to normal wear that may occur in relief valves, the
O-rings and diaphragm must be inspected periodically
and replaced as necessary. The frequency of
inspection and replacement depends upon the severity
of service conditions or the requirements of state
and federal laws. Instructions are given below for
disassembly of the relief valve and replacement of the
O-rings and diaphragm. The 1805 Series relief valves
do not have to be removed from the pipeline to inspect
internal parts. Refer to Figure 4 while servicing the
relief valves.

Disassembly/Assembly

1. To ease spring compression, remove the closing
cap (key 17, Types 1805-2, -3, and -7), loosen
the hex nut (key 15), and turn the adjusting screw
(key 14) counterclockwise.

2. Unscrew the union nut (key 16) and remove it with
the spring case (key 13), spring (key 11), and
upper spring seat (key 12).

3. Pull the O-ring holder (key 4) out of the valve guide

orice (key 2).

4. Remove the diaphragm cap screw (key 10) from
the O-ring holder. Take off the diaphragm plate
(key 9) and inspect the diaphragm (key 8).

5. Take the machine screw (key 7) out of the opposite
end of O-ring holder, remove the O-ring washer
(key 6) and inspect the O-ring (key 5).

6. Remove the valve guide orice (key 2) from the

body and check the Tetraseal® O-ring (key 3).

7. Reassemble the relief valve in reverse order of
the above steps. To ensure proper slack in the

diaphragm, tighten the union nut nger-tight only.

Turn the adjusting screw clockwise to apply some
spring force to the diaphragm. Complete the
tightening of the union nut.

Close the upstream shut-off valve, and release all
pressure from the relief valve.

Maintenance

WARNING

!

To avoid personal injury and
equipment damage, isolate the relief

valve from all pressure. Cautiously
release pressure from the relief valve

before attempting disassembly.

Tetraseal® is a mark owned by of Goshen Rubber Company.

Parts Ordering

When corresponding with your local Sales Ofce or

the factory concerning these relief valves, include
the type number and all other pertinent information
stamped on the spring case, closing cap, or on the
nameplate. Specify the eleven-character part number
when ordering new parts from the following parts list.

When ordering replacement parts, reference the key
number of each needed part as found in the following
parts list. Separate kit containing all recommended
spare parts is available.

5

1805 Series

17

14

15

13

12

18

19

11

10

9

BE9481_D

16

8

2

4

5

3

6

1

Figure 4. Type 1805-3 Relief Valve Assembly (Also typical of 1805 relief valves)

7

6

Parts List

Key Description Part Number

Parts kit
(included are keys 3, 5, and 8)
3/4 and 1 NPT body sizes R1805X00012
1-1/2 and 2 NPT body sizes R1805X00022

1 Valve Body
Types 1805-2 and -4
3/4 NPT
Cast iron 1E621119012
Ductile iron (NACE) 1F192019062
1 NPT
Cast iron 1E621219012
Ductile iron (NACE) 1F192119062
Types 1805-3 and -5
1-1/2 NPT Cast iron 1E824019012
2 NPT Cast iron 1E824319012
Type 1805-7
3/4 NPT Cast iron 1H242519012
1 NPT Cast iron 1H242619012

2 Valve Guide Orice, Aluminum

3/4 and 1 NPT body sizes 1K314709012
1-1/2 and 2 NPT body sizes 1N939909012
3* Tetraseal®/O-ring, Nitrile (NBR)
3/4 and 1 NPT body sizes 1K314806992
1-1/2 and 2 NPT body sizes 1N940306562
4 O-Ring Holder, Aluminum
3/4 and 1 NPT body sizes 1E621609092
1-1/2 and 2 NPT body sizes 1E824609092
5* O-Ring, Nitrile (NBR)
3/4 and 1 NPT body sizes 1D288806992
1-1/2 and 2 NPT body sizes 1C5622X0022
6 O-Ring Washer Stainless steel
3/4 and 1 NPT body sizes 1D335935072
1-1/2 and 2 NPT body sizes 1E824235072
7 Machine Screw, Steel
3/4 and 1 NPT body sizes 16A0429X012
1-1/2 and 2 NPT body sizes 1B420428982
8* Diaphragm, Nitrile (NBR)
3/4 and 1 NPT body sizes 1E621702052
1-1/2 and 2 NPT body sizes 1E824102052
9 Diaphragm Plate, Brass
3/4 and 1 NPT body sizes 1E621814012
1-1/2 and 2 NPT body sizes 1E824714012

1805 Series

Key Description Part Number

10 Cap Screw, Zinc-plated steel
3/4 and 1 NPT body sizes 1B290524052
1-1/2 and 2 NPT body sizes 1E760324052
11 Spring, Zinc-plated steel
3/4 and 1 NPT body sizes
5 to 35 psig / 0,34 to 2,4 bar 1B986027212
10 to 60 psig / 0,69 to 4,1 bar 1B788327022
20 to 125 psig / 1,4 to 8,6 bar 1B788427022
1-1/2 and 2 NPT body sizes
5 to 20 psig / 0,34 to 1,4 bar 1D892327022
10 to 50 psig / 0,69 to 3,5 bar 1D665927022
35 to 125 psig / 2,4 to 8,6 bar 1E543627142
12 Upper Spring Seat, Steel
3/4 and 1 NPT body sizes 1B798525062
1-1/2 and 2 NPT body sizes 1D667125072
13 Spring Case, Cast Iron
3/4 and 1 NPT body sizes 2E770819012
1-1/2 and 2 NPT body sizes 2E824919042
14 Adjusting Screw, Brass
3/4 and 1 NPT body sizes 1E770914012
1-1/2 and 2 NPT body sizes 1E543214012
15 Hex Nut, Zinc-plated steel
3/4 and 1 NPT body sizes 1A946324122
1-1/2 and 2 NPT body sizes 1D667728982
16 Union Nut, Ductile iron
3/4 and 1 NPT body sizes 1E471119062
1-1/2 and 2 NPT body sizes 1E766619062
17 Closing Cap, Brass
Types 1805-2 and -7 1E770614012
Type 1805-3 1E823914012
19 Drive Screw, Steel (4 required)
1-1/2 and 2 NPT body sizes 1E501728982
20 Screen, Stainless steel (not shown)
Type 1805-7 1E564843122
21 Snap Ring, 302 Stainles steel (not shown)
Type 1805-7 1E564937022
22 NACE Tag, 18-8 Stainless steel (not shown) 19A6034X012
23 Tag Wire, 304 Stainless steel (not shown) 1U7581X0022
24 Pipe Plug, Alloy-plated steel 1C333528992

* Recommended spare part.

Tetraseal® is a mark owned by of Goshen Rubber Company.

7

1805 Series

Industrial Regulators

Emerson Process Management
Regulator Technologies, Inc.

USA - Headquarters
McKinney, Texas 75069-1872, USA
Tel: [phone]
Outside U.S. [phone]

Asia-Pacic

Shanghai 201206, China
Tel: [phone]

Europe
Bologna 40013, Italy
Tel: [phone]

Middle East and Africa
Dubai, United Arab Emirates
Tel: [phone]

For further information visit www.sherregulators.com

The Emerson logo is a trademark and service mark of Emerson Electric Co. All other marks are the property of their prospective owners. Fisher is a mark owned by Fisher Controls International LLC,
a business of Emerson Process Management.

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. We reserve the right to modify or improve the designs or specications of such
products at any time without notice.

Emerson Process Management does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Emerson
Process Management product remains solely with the purchaser.

Natural Gas Technologies

Emerson Process Management
Regulator Technologies, Inc.

USA - Headquarters
McKinney, Texas 75069-1872, USA
Tel: [phone]
Outside U.S. [phone]

Asia-Pacic

Singapore 128461, Singapore
Tel: [phone]

Europe
Bologna 40013, Italy
Tel: [phone]
Gallardon 28320, France
Tel: [phone]

TESCOM

Emerson Process Management
Tescom Corporation

USA - Headquarters
Elk River, Minnesota 55330-2445, USA
Tels: [phone]
[phone]

Europe
Selmsdorf 23923, Germany
Tel: [phone]

Asia-Pacic

Shanghai 201206, China
Tel: [phone]

©Emerson Process Management Regulator Technologies, Inc., 1975, 2011; All Rights Reserved