Groth 1201B User manual

IOM-1201B
Rev. D 12541
Ref. ID: 96337
© 2010 Groth Corporation
Models 1201B, 1202B 1203A, 1221B, 1222B, 1223A, 1261A,
1301A, 1361A, 2301A
Installation, Operation and Maintenance Manual for
Pressure/Vacuum Relief Valves (Spring Loaded)

2
TABLE OF CONTENTS:
INTRODUCTION: 3
DESIGN, FUNCTION & OPERATION 4
GENERAL SAFETY INSTRUCTIONS 5
SAFETY WARNINGS 5
INSPECTION AND INSTALLATION 6
TABLE 1: STUD SELECTION 6
TABLE 2: BOLT TORQUE CHART 6
PREVENTIVE MAINTENANCE 7
RECOMMENDED SPARE PARTS 7
TABLE 3: PART NUMBER FOR RECOMMENDED SOFT GOOD SPARE PARTS 7
TABLE 4: VALVE DIAPHRAGM USAGE, BASED ON SETTING 7
TABLE 5: REPLACEMENT CARBON STEEL SPRING PART NUMBERS 8
TABLE 6: REPLACEMENT STAINLESS STEEL PART NUMBERS 8
DISASSEMBLY 9
TABLE 7: STEM LENGTH 9
TABLE 8: RECOMMENDED PALLET ASSEMBLY TORQUE 9
TESTING AND SETTING PROCEDURE 13
TABLE 9 - NOMINAL PALLET ASSEMBLY WEIGHT PER UNIT OF PRESSURE 13
MODEL INFORMATION 19
PRODUCT LIMITED WARRANTY 19

3
INTRODUCTION:
The Groth Spring-Loaded Pressure / Vacuum Relief Valves (PV) are designed to protect tanks from damage caused
by overpressure or over vacuum conditions. By containing product vapors PV valves reduce costly product
evaporation losses due to normal tank breathing. In addition, atmospheric contamination is reduced by containing
product vapors until tank pressure reaches the set pressure of the PV valve.
All pallets include Groth's special "cushioned air" seating. Fluoropolymer seating diaphragms are standard; they
minimize sticking caused by resinous vapors and atmospheric moisture. The valve has a self draining housing body
and drip rings to protect seating surfaces from condensate and freezing. This design also avoids dangerous pressure
or vacuum buildup due to binding or clogging of the vent. Diaphragms are available in Buna-N, FKM and other
elastomers; metal-to-metal seat can be provided when required.
To insure the proper alignment of seating surfaces, there is both peripheral and stem pallet guidance. As with all
Groth products, every spring loaded valve is factory inspected and tested.
Pressure and Vacuum Relief Valves are preset at the factory in accordance with the purchase order. These settings
are printed on the stainless steel name tag.
All PV valves require regular inspection and maintenance, the frequency depending upon actual conditions. The
gasket between the vent and the nozzle flange should also be regularly inspected.
The valve must be maintained by a knowledgeable valve technician. It should only be assembled under clean
conditions - preferably in a shop environment. Carefully read and understand this Manual before installing or
repairing this valve.
For information not contained in this manual, please contact:
Groth Corporation
13650 N. Promenade Blvd
Stafford, TX 77477
281-295-6800 (Phone)
281-295-6995 (Fax)

4
DESIGN, FUNCTION & OPERATION
Pressure Relief: As the pressure in the storage tank
increases the vacuum pallet is held shut. When the
set pressure is reached the pressure pallet lifts and
relieves to a header (or to atmosphere if it is not a pipe
away valve).
Vacuum Relief: As a vacuum is drawn on the
storage tank (for example, when fluid is being
pumped out), the pressure pallet is held shut by
tank vacuum. When the vacuum setting is
reached, the pallet lifts and air is drawn in from
the atmosphere and flows into the tank.
NOTE 1: Minimum recommended clearance between vacuum inlet port and tank roof is nominal flange bore of valve.
Typical valve installation on a tank or vessel is illustrated in Fig.1 on the next page using a Model 1221A
Pressure/Vacuum Relief Valve. Most tanks will have provision for an operating relief valve, an emergency relief
valve, and a blanketing regulator that maintains a positive gas pressure in the tank.
The combination of these valves and regulator are designed to ensure that the tank is protected from both excess
vacuum and pressure conditions.
Figure 1 - Typical Tank Installation
Tank protection equipment typically includes an operating valve which is designed to provide pressure/vacuum relief
under normal pump in/out and thermal breathing conditions. An emergency relief valve can also provide both
pressure and vacuum relief, normally sized to provide pressure relief if there is a fire in the immediate vicinity of the
tank. It may also be sized by the tank designer to provide protection in the event of equipment failure (such as the
rupture of a process steam line or an inert gas blanketing system failing “wide open”) or operator error.
A typical tank installation is shown in Fig. 1 which includes the following Groth products:
Model 1221B PV’ Valve
Model 3011 Blanket Gas Regulator
Model 2400 Emergency Relief Valve

5
GENERAL SAFETY INSTRUCTIONS
This section is an overview of safety guidelines that should be followed during the installation, operation and
maintenance of Groth Pressure / Vacuum Relief Valves. To understand the context of these instructions and
warnings, it is necessary to completely read and understand the contents of this manual.
The purpose of a pressure/vacuum relief valve is to prevent excessive pressure or vacuum in a tank or process
system. The valve must be designed for the proper MAWP and flow requirements of the system. Consult API
Standard 2000 for tank protection sizing procedures. An improperly specified or functioning relief valve may result in
structural damage to the tank or system, and can cause severe personal injury or death.
SAFETY WARNINGS
PRESSURE/VACUUM CONSERVATION VALVES ARE DESIGNED TO PROVIDE FULL RATED CAPACITY AT
100% OVER-PRESSURE. IF THE VALVE IS TO BE OPERATED AT A REDUCED OVER-PRESSURE, CONSULT
FACTORY FOR ACTUAL FLOW CAPACITY UNDER SPECIFIED CONDITIONS.
THE TANK PRESSURE REQUIRED TO DISCHARGE THE NORMAL OR EMERGENCY VENTING
REQUIREMENTS OF THE TANK WILL BE INCREASED BY THE AMOUNT OF BACK PRESSURE IN THE
DISCHARGE HEADER, ON A PIPE AWAY VALVE CONFIGURATION. MAXIMUM POSSIBLE DISCHARGE
HEADER PRESSURE MUST BE CONSIDERED WHEN SIZING THE PRESSURE RELIEF VALVE.
DO NOT CHANGE PRESSURE RATING BY ADDING ADDITIONAL WEIGHTS TO PALLET ASSEMBLY OR
ADJUSTING SPRING COMPRESSION WITHOUT CONSULTING FACTORY. ADDING WEIGHTS OR
ADJUSTING SPRING COMPRESSION TO A VALVE MAY RESTRICT PALLET LIFT AND REDUCE FLOW
CAPACITY. DO NOT CHANGE PRESSURE RATINGS BY ADDING ADDITIONAL WEIGHTS TO THE PALLET
ASSEMBLY WITHOUT CONSULTING THE FACTORY OR YOUR LOCAL GROTH REPRESENTATIVE. ADDING
WEIGHTS TO A VALVE MAY RESTRICT PALLET LIFT AND REDUCE THE VALVES’ RATED FLOW CAPACITY.
WHEN INSTALLING THE WEIGHT LOADED PALLET ASSEMBLY IN THE VALVE, MAKE SURE THAT THE
STEM IS STRAIGHT AND FITS INTO THE GUIDE IN THE COVER. IF THE STEM IS COCKED, THE PALLET
ASSEMBLY MAY NOT OPEN FULLY AND THE TANK CAN BE OVER-PRESSURED. UNDER THESE
CONDITIONS, THE VALVE WILL NOT PROTECT THE TANK FROM RUPTURING DUE TO CHANGES IN
INTERNAL PRESSURE. TANK FAILURE CAN CAUSE MATERIAL DAMAGE AND LOSS AND RESULT IN
SEVERE PERSONAL INJURY OR DEATH.
DO NOT MIX WEIGHT LOADED PALLET ASSEMBLIES FROM DIFFERENT VALVES. FAILURES TO ENSURE
THAT THE WEIGHT LOADED PALLET ASSEMBLIES ARE INSTALLED IN THE ORIGINAL AND CORRECT
LOCATION CAN CHANGE THE PRESSURE OR VACUUM RELIEF SETTINGS. THIS CAN CAUSE A TANK
FAILURE.
DO NOT LOOSEN HEX NUTS UNTIL ALL SPRING COMPRESSION HAS BEEN RELEASED. SPRING PRE-
LOAD IS SUBSTANTIAL AND COULD CAUSE SEVERE PERSONAL INJURY IF FASTENERS WERE REMOVED
WITH THE SPRING COMPRESSED.
DO NOT ATTEMPT TO REMOVE THE VALVE FROM THE TANK OR PROCESS VESSEL WITHOUT FIRST
BLEEDING ALL PRESSURE FROM THE SYSTEM. ALTERNATIVE MEANS OF PRESSURE RELIEF MUST BE
PROVIDED WHEN THE VALVE IS OUT OF SERVICE.
THE VALVE HAS BEEN EXPOSED TO PROCESS VAPORS WHILE IN SERVICE. OBSERVE ALL PLANT
PROCEDURES AND MATERIAL SAFETY DATA SHEETS (MSDS) FOR THE PRODUCTS IN THE SYSTEM
WHEN INSPECTING, ADJUSTING OR SERVICING THE VALVE. TAKE APPROPRIATE SAFETY
PRECAUTIONS REGARDING EYE PROTECTION, RESPIRATION AND SKIN CONTACT.
DO NOT ADD ANY WEIGHT TO THE PALLET ASSEMBLY, CHANGE THE ADJUSTMENT SCREW (CHANGING
SET PRESSURE OR VACUUM), OR CHANGE PALLET STEM WITHOUT FIRST CONSIDERING THE
ALLOWABLE TANK PRESSURE OR WITHOUT MEASURING DESIGN LIFT TO ENSURE THE LIFT IS NOT
RESTRICTED. RESTRICTING VALVE LIFT COULD “CHOKE” THE VALVE AND NOT ALLOW FOR FULL
RATED CAPACITY. CHANGING THE WEIGHT OR ADJUSTMENT OF A SPRING COULD ALSO RESTRICT THE
LIFT OF A VALVE AT A SPECIFIED OVERPRESSURE, REDUCING THE RATED CAPACITY OF THE VALVE.
UNDER THESE CONDITIONS, THE VALVE WILL NOT PROTECT THE TANK FROM RUPTURING DUE TO
CHANGES IN INTERNAL PRESSURE. TANK FAILURE CAN CAUSE MATERIAL DAMAGE AND LOSS AND
RESULT IN SEVER PERSONAL INJURY OR DEATH.

6
INSPECTION AND INSTALLATION
The pressure/vacuum relief valve is carefully packaged to prevent damage or contamination during shipping. Inspect
all equipment when it is received; report any damage to the carrier immediately. The valve should be protected
during handling and storage. Keep all the ports plugged to prevent intrusion of foreign materials. Before installation,
inspect the unit for indications of physical damage or internal contamination. If these are observed, the valve must be
disassembled, cleaned and repaired before installation.
Groth's spring loaded PV Valves are designed to provide tank protection for set-pressures to 15 PSIG and vacuum to
12 PSIG. The valves provide full rated flow capacity at 100% over-pressure. Consult factory for performance under
other conditions.
The valve should be installed in a vertical position as shown in Figure 1.
Follow the torque guidelines listed in Table 2 to avoid produce damage due to excessive fastener tightening. The
valves are NOT rated for full flange pressure and do not require high bolting torque. Consult factory for special
applications; torque values assume a maximum MAWP of 30 PSIG.
The following guidelines should be observed at installation:
1. Remove any flange protectors and discard all packing material.
2. Inspect the gasket seating surface of the tank nozzle flange. It must be clean, free of scratches, corrosion, tool
marks, and flat.
3. Aluminum valves are furnished with flat face flanges; they should only be installed on a mating flat faced flange
with a full faced gasket.
4. Inspect the gasket; make sure that the material is suitable for the application.
5. Lubricate all studs and nuts with an appropriate thread lubricant. If the valve will see high temperature service or
stainless steel fasteners are used, select an anti-seize compound such as moly-disulfide.
6. Center the gasket within the bolt circle.
7. Set the valve carefully on the nozzle. Install the studs and tighten nuts hand tight. For stud selection for blind
tapped holes see Table 1 below:
TABLE 1: STUD SELECTION
Inlet Flange Thread
Size Recommended Stud Length
2" 5/8" - 11 2.25"
3" 5/8" - 11 2.50"
4" 5/8" - 11 2.50"
6" 3/4" - 10 3.00"
8" 3/4" - 10 3.00"
10" 7/8" - 9 3.50"
12" 7/8" - 9 3.50"
8. Torque all fasteners to half the value listed in the table below in a staggered, alternating pattern.
9. Make sure that the flanges are not distorted and that the gasket is evenly compressed.
10. Make up the final torque and check that no further nut rotation occurs at the specified torque value, as specified in
Table 2.
TABLE 2: BOLT TORQUE CHART, LB-IN [N-m]*
Inlet Flange Raised Face Flat Face Number
Bolts
2" 30 [3.4] 60 [6.8] 4
3" 54 [6.1] 108 [12.2] 4
4" 42 [4.7] 78 [8.8] 8
6" 90 [10.2] 150 [16.9] 8
8" 126 [14.2] 228 [25.8] 8
10" 138 [15.6] 246 [27.8] 12
12" 186 [21.0] 348 [39.3] 12
*Average values based on a nitrile binder synthetic gasket,
1/32" thick and lubricated threads.

7
PREVENTIVE MAINTENANCE
Groth Corporation recommends that all service performed on a pressure/vacuum relief valve be done at the factory or a factory
authorized repair center. Trained mechanics with specialized test equipment will ensure that the valve is properly maintained
and accurately set.
It is important to regularly inspect and clean the diaphragm, guides and seating surfaces for the most effective valve
performance. Frequency of valve inspection and maintenance should be based on the experience gained in each application. It
is recommended that the valve be removed for inspection of wetted components at least once per year. Refer to Fig. 5 which
illustrates a typical Pressure/Vacuum relief valve to disassemble the unit.
RECOMMENDED SPARE PARTS
The following spare parts should be stocked for maintenance purposes:
TABLE 3: PART NUMBER FOR RECOMMENDED SOFT GOOD SPARE PARTS
VALVE
SIZE
FEP Diaphragm
20 mil
(Spring Loaded)
FEP Diaphragm
10 mil
(Weight Loaded)
FEP Diaphragm
20 mil
(Weight Loaded)
Gasket, Outlet
Fluoropolymer
(bottom)
Gasket, Cover
Fluoropolymer
(top)
O-Ring
(machined pallet)
FKM
2" DPH1201027320 DPH1200027310 DPH1200027320 GKT1220027102 GKT1200027101 0267010U2
3" DPH1201037320 DPH1200037310 DPH1200037320 GKT1220037102 GKT1200037101
4" DPH1201047320 DPH1200047310 DPH1200047320 GKT1220047102 GKT1200047101
6" DPH1201067320 DPH1200067310 DPH1200067320 GKT1220067102 GKT1200067101
0267012U2
8" DPH1201087320 DPH1200087310 DPH1200087320 GKT1220087102 GKT1200087101
10" DPH1201107320 DPH1200107310 DPH1200107320 GKT1220107102 GKT1200107101
12" DPH1201127320 DPH1200127310 DPH1200127320 GKT1220127102 GKT1200127101
TABLE 4: VALVE DIAPHRAGM USAGE, BASED ON SETTING
Setting < 4 OSI 4 - 8 OSI > 8 OSI
Diaphragm 10 mil 20 mil 10 mil 20 mil 10 mil 20 mil
Quantity 1 --- --- 1 1 1
* Please provide the valve serial number and pressure/vacuum settings when ordering replacement parts.

8
Replacement Springs
To order original Groth replacement springs, find the desired pressure range from the tables below and select the corresponding
part number for the valve size:
TABLE 5: REPLACEMENT CARBON STEEL SPRING PART NUMBERS
Set
Range
PSIG
Carbon Steel Spring Part Numbers (*)
2" 3" 4" 6" 8" 10" 12"
1.0 to 1.3 SPR1201020120 SPR1201030120 SPR1201040120 SPR1201060120 SPR1201080120 SPR1201100120 SPR1201120120
1.4 to 1.8 SPR1201020220 SPR1201030220 SPR1201040220 SPR1201060220 SPR1201080220 SPR1201100220 SPR1201120220
1.9 to 2.4 SPR1201020320 SPR1201030320 SPR1201040320 SPR1201060320 SPR1201080320 SPR1201100320 SPR1201120320
2.5 to 3.2 SPR1201020420 SPR1201030420 SPR1201040420 SPR1201060420 SPR1201080420 SPR1201100420 SPR1201120420
3.3 to 4.2 SPR1201020520 SPR1201030520 SPR1201040520 SPR1201060520 SPR1201080520 SPR1201100520 SPR1201120520
4.3 to 5.5 SPR1201020620 SPR1201030620 SPR1201040620 SPR1201060620 SPR1201080620 SPR1201100620 SPR1201120620
5.6 to 7.2 SPR1201020720 SPR1201030720 SPR1201040720 SPR1201060720 SPR1201080720 SPR1201100720 SPR1201120720
7.3 to 9.4 SPR1201020820 SPR1201030820 SPR1201040820 SPR1201060820 SPR1201080820 SPR1201100820 SPR1201120820
9.5 to 12.2 SPR1201020920 SPR1201030920 SPR1201040920 SPR1201060920 SPR1201080920 SPR1201100920 SPR1201120920
12.3 to 15.0 SPR1201021020 SPR1201031020 SPR1201041020 SPR1201061020 SPR1201081020 SPR1201101020 SPR1201121020
TABLE 6: REPLACEMENT STAINLESS STEEL PART NUMBERS
Set
Range
PSIG
17-7 PH Stainless Steel Spring Part Numbers (*)
2" 3" 4" 6" 8" 10" 12"
1.0 to 1.3 SPR1201020105 SPR1201030105 SPR1201040105 SPR1201060105 SPR1201080105 SPR1201100105 SPR1201120105
1.4 to 1.8 SPR1201020205 SPR1201030205 SPR1201040205 SPR1201060205 SPR1201080205 SPR1201100205 SPR1201120205
1.9 to 2.4 SPR1201020305 SPR1201030305 SPR1201040305 SPR1201060305 SPR1201080305 SPR1201100305 SPR1201120305
2.5 to 3.2 SPR1201020405 SPR1201030405 SPR1201040405 SPR1201060405 SPR1201080405 SPR1201100405 SPR1201120405
3.3 to 4.2 SPR1201020505 SPR1201030505 SPR1201040505 SPR1201060505 SPR1201080505 SPR1201100505 SPR1201120505
4.3 to 5.5 SPR1201020605 SPR1201030605 SPR1201040605 SPR1201060605 SPR1201080605 SPR1201100605 SPR1201120605
5.6 to 7.2 SPR1201020705 SPR1201030705 SPR1201040705 SPR1201060705 SPR1201080705 SPR1201100705 SPR1201120705
7.3 to 9.4 SPR1201020805 SPR1201030805 SPR1201040805 SPR1201060805 SPR1201080805 SPR1201100805 SPR1201120805
9.5 to 12.2 SPR1201020905 SPR1201030905 SPR1201040905 SPR1201060905 SPR1201080905 SPR1201100905 SPR1201120905
12.3 to 15.0 SPR1201021005 SPR1201031005 SPR1201041005 SPR1201061005 SPR1201081005 SPR1201101005 SPR1201121005

9
DISASSEMBLY
WEIGHT LOADED PALLET ASSEMBLY
1. Loosen and remove all hex nuts and washers.
2. Remove the vent cover or weatherhood from the valve body.
3. Remove the pallet assembly by firmly grasping the stem and lifting up. Depending on the pressure/vacuum settings of the
particular valve, weight plates may have been added to the pallet assembly. The weights and pallets must be reinstalled in
their original locations. Make sure that all weight plates stay with the appropriate pallet assembly. If working with more than
one valve tag the assemblies as they are removed from the valves.
4. Carefully inspect all guides for corrosion, damage or product build up. Also inspect the guide hole in the vacuum cover.
Check the metal seating surfaces for pitting or build up. It is recommended to replace all soft goods including diaphragm, O-
Ring (for machined pallets, Figure 2) and cover gasket.
TABLE 7: STEM LENGTH - IN. [CM]
Valve Size Valve Model
In [mm] 2300A 1200A 1220A / 1260A 1300A / 1360A
Pressure Port Vacuum Port
2 [50] 5.50 [14.0] 4.63 [11.8] 4.63 [11.8]
3 [80] 5.50 [14.0] 5.50 [14.0] 5.50 [14.0]
4 [100] 7.81[19.8] 7.81 [19.8] 5.50 [14.0]
6 [150] 10.75 [27.3] 10.75 [27.3] 7.19 [18.3]
8 [200] 10.75 [27.3] 12.13 [30.8] 10.75 [27.3]
10 [250] 10.75 [27.3] 13.50 [34.3] 10.75 [27.3]
12 [300] 12.13 [30.8] 15.00 [38.1] 12.13 [30.8]
TABLE 8: RECOMMENDED PALLET ASSEMBLY TORQUE
STEM THREAD
SIZE
PALLET ASSEMBLY TORQUE
REQUIREMENT FT-LBS [N-m]
PVDF STEM METALLIC STEM (ALUMINUM /
STAINLESS STEEL)
1/4" HAND TIGHT 4 [5.4]
3/8" HAND TIGHT 16 [21.7]
1/2" HAND TIGHT N / A
NOTE: If the seat is damaged it must be lapped using a ground flat metal disc and a fine grit emery cloth attached to the disc.
Wipe seating surface clean before proceeding.
Figure 2 - Pallet Assembly Detail
5. Prior to final assembly, verify that the pallet and weights are back in their proper location. Assemble in reverse order. Make
sure that pallet assembly is flat on the seat and that the stem is not cocked when the cover is installed. Oil, grease or other
lubricant are not required on guides or other metal surfaces of valves, and can hinder free movement. If the valve is in high
temperature service or stainless steel external fasteners are used, apply an anti-seize compound such as moly-disulfide to
all threaded components. Tighten all hex nuts firmly.

10
SPRING LOADED PALLET ASSEMBLY
1. Remove cap and hex jam nut.
2. Carefully measure and record the distance from the top of the adjustment screw to the top of the spring chamber. (Dimension
"D" - See Figure 3).
3. Relieve all spring compression by turning the adjustment screw counterclockwise.
4. Loosen and remove all hex nuts and washers.
5. Lift the spring chamber from the body.
6. Remove the upper spring button and spring. Remove the pallet assembly by firmly grasping the stem and lifting up. If more
than one valve is being disassembled, tag the assemblies as they are removed from the valves.
7. Carefully inspect all guides for corrosion, damage or product build up. Also inspect the adjustment screw and spring chamber
(#2) for thread damage or galling. Check the metal seating surfaces for pitting or build up. It is recommended that all soft
goods including diaphragms, O-Ring and spring chamber gasket be replaced.
NOTE: If the seat is damaged it must be lapped using a ground flat metal disc and a fine grit emery cloth attached to the disc.
Wipe seating surface clean before proceeding.
8. Prior to final assembly, verify that the pallet and spring are back in their proper location. Assemble in reverse order. Make
sure that pallet assembly is flat on the seat and that the stem is not cocked when the spring chamber is installed. Oil, grease
or other lubricant are not required on guides or other metal surfaces of valves, and can hinder free movement. Lubricate the
adjustment screw threads with an appropriate thread lubricant. If the valve is in high temperature service or stainless steel
external fasteners are used, apply an anti-seize compound such as moly-disulfide to all threaded components. Tighten all
hex nuts firmly.
9. If the spring is being re-used, compress it by turning the adjustment screw clockwise until the distance from the top of the
adjustment screw to the top of spring chamber matches the distance "D" measured in Step 2; proceed to Step 11.
10. If the spring is replaced, use only original springs supplied by Groth Corporation and follow the Procedure illustrated below:
11.Replace and tighten hex jam nut firmly. Replace cap.
Figure 3: Spring Setting Procedure
STEP 1
STEP 2 STEP 3 STEP 4
After removing the adjustment
screw (#4) measure the
distance from top of spring
chamber to counter bore on
spring button for the dimension
"A".
Measure overall
length of
adjustment screw
for dimension "B".
This is the required
compression to achieve
the design set pressure.
Consult factory for
determination of “C”
dimension.
Use the following calculation to
obtain the "D" dimension.
Compress the spring by turning
the adjustment screw clockwise
accordingly.
D = B-A-C

11
TESTING AND SETTING PROCEDURE
1. Before starting to reassemble a valve, calculate the nominal pressure and vacuum pallet assembly weights, as shown in
Example 1. Weigh all pallet assemblies to ensure the correct settings. Record pallet assembly weight(s) on factory test
report.
Example: Pallet Assembly Weight Calculation (PAW)
6" Valve set at 7.5 OSI Read weight at 1.0 OSI from table 10 Weight = 3.04 Lb.
Multiple weight by set pressure PAW (*) = 3.04 x 7.5 = 22.8 Lb.
(*) = Includes pallet, retainer plate, stem, diaphragm, weight plates and fasteners.
TABLE 9 - NOMINAL PALLET ASSEMBLY WEIGHT PER UNIT OF PRESSURE (*)
Valve Size
SET 2" 3" 4" 6" 8" 10" 12"
[Lb.] [kg] [Lb.] [kg] [Lb.] [kg] [Lb.] [kg] [Lb.] [kg] [Lb.] [kg] [Lb.] [kg]
1.0 OSI 0..41 0.18 0.84 0.38 1.42 0.64 3.04 1.38 5.28 2.40 7.52 3.42 10.1 4.61
1.0 IN WC 0.24 0.11 0.48 0.22 0.82 0.37 1.76 0.80 3.05 1.39 4.35 1.98 5.86 2.67
1.0 mbar 0.09 0.04 0.19 0.09 0.33 0.15 0.71 0.32 1.23 0.56 1.74 0.79 2.35 1.07
2. After final assembling, mount the valve on a Tank Vent Test Stand (TVTS) and slowly raise the pressure at the flow rate
specified below:
Valve Size Test Flow Rate
2" - 6" 0.5 SCFH
8"- 12" 5.0 SCFH
ACCEPTANCE CRITERIA: The pressure gauge shall maintain a pressure equal to or greater than 75% of set pressure for a
one minute period while the specified flow rate is maintained. This test shall be successfully performed three consecutive
times.
3. If the valve fails to meet the 75% criteria, it must be disassembled and the seat, pallet, and or diaphragms repaired or
replaced.
4. Set pressure and / or vacuum must also be tested. To test for set pressure / vacuum, slowly increase the pressure / vacuum
to the valve being tested. Increase until there is audible leakage from the valve seat. Closely monitor the pressure /
vacuum at the gauge, when an increase in flow to the valve no longer raises the pressure at the gauge the set pressure /
vacuum is reached.
5. Repeat Step 4 three consecutive times. Record all three tests on the factory test report.
6. A copy of the Test Report shall be maintained with the Valve Maintenance Records.

12
Groth Model 1201B Pressure/Vacuum Relief Valve

13
ITEM DESCRIPTION CARBON
A
LUMINUM STAINLESS
1 Body CS Aluminum 316 SS
2 Spring Chamber CS Aluminum 316 SS
3 Spring Button CS CS 316 SS
4 Adjustment Screw SS SS SS
5 Gasket, Cap * SS SS SS
6 Cap CS CS 316 SS
7 Hex Jam Nut CS CS SS
8 Stem 316 SS 316 SS 316 SS
9 Spring CS CS SS
10 Hex Bolt CS CS 316 SS
11 Lock Washer CS CS 316SS
12 Support Ring CS CS 316 SS
13 Weatherhood CS Aluminum 316 SS
14 Weatherhood Post 316 SS 316 SS 316 SS
15 O-Ring * FKM FKM FKM
16 Pallet 316 SS 316 SS 316 SS
17 Diaphragm * Fluoropolymer Fluoropolymer Fluoropolymer
18 Retainer Plate 316 SS 316 SS 316 SS
19 Hex Lock Nut 316 SS 316 SS 316 SS
20 Lock Washer CS CS 316SS
21 Hex Nut CS CS 316SS
22 Screen SS SS 316 SS
23 Vent Cover - Vac CS Aluminum 316 SS
24 Stem - Vac 316 SS 316 SS 316 SS
25 Stud CS CS 316SS
26 Lock Washer CS CS 316SS
27 Hex Nut CS CS 316 SS
28 Gasket-Cover, Vac * Non-Asb Non-Asb Non-Asb
29 Guide Post - Vac 316 SS 316 SS 316 SS
30 Pallet - Vac 316 SS 316 SS 316 SS
31 Diaphragm - Vac * Fluoropolymer Fluoropolymer Fluoropolymer
32 Retainer Plate - Vac 316 SS 316 SS 316 SS
33 Lock Washer 316 SS 316 SS 316 SS
34 Hex Nut 316 SS 316 SS 316 SS
35 O-Ring (Machined Pallet) * # FKM FKM FKM
* = Recommended Spare Parts
# = See Figure 2 Item 39

14
Groth Model 1221B Pressure/Vacuum Relief Valve

15
ITEM DESCRIPTION CARBON
A
LUMINUM STAINLESS
1 Outlet CS Aluminum 316 SS
2 Spring Chamber CS Aluminum 316 SS
3 Spring Button CS CS 316 SS
4 Adjustment Screw SS SS SS
5 Gasket, Cap * SS SS SS
6 Cap CS CS 316 SS
7 Hex Jam Nut CS CS SS
8 Stem 316 SS 316 SS 316 SS
9 Spring CS CS SS
10 Stud CS CS 316 SS
11 Lock Washer CS CS 316SS
12 Hex Nut CS CS 316 SS
13 Gasket- Spring Chamber * Non-Asb Non-Asb Non-Asb
14 Guide Post 316 SS 316 SS 316 SS
15 O-Ring * FKM FKM FKM
16 Pallet 316 SS 316 SS 316 SS
17 Diaphragm * Fluoropolymer Fluoropolymer Fluoropolymer
18 Retainer Plate 316 SS 316 SS 316 SS
19 Hex Lock Nut 316 SS 316 SS 316 SS
20 Plug CS CS SS
21 Gasket * Fluoropolymer Fluoropolymer Fluoropolymer
22 Stud CS CS 316SS
23 Lock Washer CS CS 316SS
24 Hex Nut CS CS 316 SS
25 Vent Cover - Vac CS Aluminum 316 SS
26 Stem - Vac 316 SS 316 SS 316 SS
27 Stud CS CS 316SS
28 Lock Washer CS CS 316SS
29 Hex Nut CS CS 316 SS
30 Gasket-Cover, Vac * Fluoropolymer Fluoropolymer Fluoropolymer
31 Guide Post - Vac 316 SS 316 SS 316 SS
32 Body CS Aluminum 316 SS
33 Pallet - Vac 316 SS 316 SS 316 SS
34 Diaphragm - Vac * Fluoropolymer Fluoropolymer Fluoropolymer
35 Retainer Plate - Vac 316 SS 316 SS 316 SS
36 Lock Washer 316 SS 316 SS 316 SS
37 Hex Nut 316 SS 316 SS 316 SS
38 O-Ring, (Machined Pallet) * # FKM FKM FKM
* = Recommended Spare Parts
# = See Figure 2 Item 39

16
Groth Model 1261A Pressure/Vacuum Relief Valve
ITEM DESCRIPTION CARBON
A
LUMINUM STAINLESS
1 Outlet CS Aluminum 316 SS
2 Spring Chamber CS Aluminum 316 SS
3 Spring Button CS CS 316 SS
4 Adjustment Screw SS SS SS
5 Gasket, Cap * SS SS SS
6 Cap CS CS 316 SS
7 Hex Jam Nut CS CS SS
8 Stem 316 SS 316 SS 316 SS
9 Spring CS CS SS
10 Stud CS CS 316 SS
11 Lock Washer CS CS 316SS
12 Hex Nut CS CS 316 SS
13 Gasket- Spring Chamber * Fluoropolymer Fluoropolymer Fluoropolymer
14 Guide Post 316 SS 316 SS 316 SS
15 O-Ring * FKM FKM FKM
16 Pallet 316 SS 316 SS 316 SS
17 Diaphragm * Fluoropolymer Fluoropolymer Fluoropolymer
18 Retainer Plate 316 SS 316 SS 316 SS
19 Hex Lock Nut 316 SS 316 SS 316 SS
20 Plug CS CS SS
21 Gasket- Inlet * Fluoropolymer Fluoropolymer Fluoropolymer
22 Stud CS CS 316SS
23 Lock Washer CS CS 316SS
24 Hex Nut CS CS 316 SS
25 Inlet CS Aluminum 316 SS
* = Recommended Spare Parts

17
Groth Model 1301A Vacuum Relief Valve
ITEM DESCRIPTION CARBON
A
LUMINUM STAINLESS
1 Body CS Aluminum 316 SS
2 Spring Chamber CS Aluminum 316 SS
3 Spring Button CS CS 316 SS
4 Adjustment Screw SS SS SS
5 Gasket, Cap * SS SS SS
6 Cap CS CS 316 SS
7 Hex Jam Nut CS CS SS
8 Stem 316 SS 316 SS 316 SS
9 Spring CS CS SS
10 Stud CS CS 316 SS
11 Lock Washer CS CS 316SS
12 Hex Nut CS CS 316 SS
13 Gasket- Spring Chamber * Fluoropolymer Fluoropolymer Fluoropolymer
14 Guide Post 316 SS 316 SS 316 SS
15 O-Ring * FKM FKM FKM
16 Pallet 316 SS 316 SS 316 SS
17 Diaphragm * Fluoropolymer Fluoropolymer Fluoropolymer
18 Retainer Plate 316 SS 316 SS 316 SS
19 Hex Lock Nut 316 SS 316 SS 316 SS
20 Gasket- Cover * Fluoropolymer Fluoropolymer Fluoropolymer
21 Hex Bolt CS CS 316SS
22 Lock Washer CS CS 316SS
23 Hex Nut CS CS 316 SS
24 Cover CS CS 316 SS
* = Recommended Spare Parts

18
Groth Model 1361A Vacuum Relief Valve
ITEM DESCRIPTION CARBON
A
LUMINUM STAINLESS
1 Outlet CS Aluminum 316 SS
2 Spring Chamber CS Aluminum 316 SS
3 Spring Button CS CS 316 SS
4 Adjustment Screw SS SS SS
5 Gasket, Cap * SS SS SS
6 Cap CS CS 316 SS
7 Hex Jam Nut CS CS SS
8 Stem 316 SS 316 SS 316 SS
9 Spring CS CS SS
10 Stud CS CS 316 SS
11 Lock Washer CS CS 316SS
12 Hex Nut CS CS 316 SS
13 Gasket * Fluoropolymer Fluoropolymer Fluoropolymer
14 Guide Post 316 SS 316 SS 316 SS
15 O-Ring * FKM FKM FKM
16 Pallet 316 SS 316 SS 316 SS
17 Diaphragm * Fluoropolymer Fluoropolymer Fluoropolymer
18 Retainer Plate 316 SS 316 SS 316 SS
19 Hex Lock Nut 316 SS 316 SS 316 SS
20 Plug CS CS SS
* = Recommended Spare Parts

19
Groth Model 2301A Pressure Relief Valve
ITEM DESCRIPTION CARBON
A
LUMINUM STAINLESS
1 Base CS Aluminum 316 SS
2 Spring Chamber CS Aluminum 316 SS
3 Spring Button CS CS 316 SS
4 Adjustment Screw SS SS SS
5 Gasket, Cap * SS SS SS
6 Cap CS CS 316 SS
7 Hex Jam Nut CS CS SS
8 Stem 316 SS 316 SS 316 SS
9 Spring CS CS SS
10 Hex Bolt CS CS 316 SS
11 Lock Washer CS CS 316SS
12 Support Ring CS CS 316 SS
13 Weatherhood CS Aluminum 316 SS
14 Weatherhood Post 316 SS 316 SS 316 SS
15 O-Ring * FKM FKM FKM
16 Pallet 316 SS 316 SS 316 SS
17 Diaphragm * Fluoropolymer Fluoropolymer Fluoropolymer
18 Retainer Plate 316 SS 316 SS 316 SS
19 Hex Lock Nut 316 SS 316 SS 316 SS
20 Lock Washer CS CS 316SS
21 Hex Nut CS CS 316SS
22 Screen SS SS 316 SS
* = Recommended Spare Parts

20
MODEL INFORMATION
The nameplate on the Valve contains the Model Number, Serial Number, set pressures and flow capacity at a specified over-
pressure. The Model Number contains additional information about materials of construction, soft goods and options. The following
chart will assist in relating the Model Number to the characteristics of your valve:
MODEL SIZE MATERIAL OPTIONS
------ ------ -------------
1201B 02" Pallet Z =Special Options
1202B 03" Seat O =No Specials
1203A 04" Body
1221B 06" J = Steam Jacket
1222B 08" 1 =Aluminum O = No Jacket
1223A 10" 3 =Carbon Steel
1261A 12" 5 =316 SS
1301A Z = Special SEAT MATERIAL
1361A B = Buna-N
2301A T = Fluoropolymer
V = FKM
M = Metal-to-Metal
Z = Special
EXAMPLE: 1221A-02-355-TOO indicates a 2" Model 1221A with Carbon Steel body, 316SS seat and pallet, Fluoropolymer seat
diaphragms and no special options.
PRODUCT LIMITED WARRANTY
Only Groth’s Product Limited Warranty terms apply to purchase orders accepted by Groth Corporation.
A.Seller warrants that products that are manufactured by Seller are manufactured in accordance with published specifications
and free from defects in materials and/or workmanship for a period of (12) twelve months. Seller, at its option, will repair or
replace any products returned intact to the factory, transportation charges prepaid, which Seller, upon inspection,
determines to be defective in material and/or workmanship. The foregoing shall constitute the sole remedy for any breach of
Seller’s warranty.
B.THERE ARE NO UNDERSTANDINGS, AGREEMENTS, REPRESENTATIONS, OR WARRANTIES, EXPRESS OR
IMPLIED (INCLUDING MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE REGARDING PRODUCTS)
UNLESS SPECIFIED IN THE SALES CONTRACT. THIS CONTRACT STATES THE ENTIRE OBLIGATION OF SELLER.
Seller makes no warranties, either express or implied, except as provided herein, including without limitation thereof,
warranties as to marketability, merchantability, for a particular purpose or use, or against infringement of any patent of
products. In no event shall Seller be liable for any direct, incidental or consequential damages of any nature, or losses or
expenses resulting from any defective new product or the use of any such product, including any damages for loss of time,
inconvenience, or loss of use of any such product.
C.The original Manufacturer shall be solely responsible for the design, development, supply, production, and performance of
its products hereunder, and the protection of its trade name or names, if any. It assumes no responsibility, for products
modified or changed by its agent or customer, or any other third party. Any such modifications or changes to products sold
by Seller hereunder shall make the product limited warranty null and void.
D.Groth assumes no responsibility for products modified or changed by Customer or any other third party. Any such
modifications or changes to products sold by Groth hereunder shall make the product limited warranty null and void. Groth
shall be under no obligation to manufacture, sell or supply, or to continue to manufacture, sell, or supply any of the products.