Groth 1720A User Manual
Page 2
2
TABLE OF CONTENTS:
DESCRIPTION
PAGE
Introduction 2
Valve Design & Function
3
Safety Warnings
4
Inspection and Storage
4
Installation
4 & 5
Maintenance
6 & 7
Test Procedure & Weight Blocks
8 & 9
Bill of Materials & Submittal Drawings
Model 1720A
10
Model 1760A
11
Abbreviations 11
Model Identification
12
Product Limited Warranty
12
LIST OF FIGURES
Fig. 1- Typical Tank Installation
3
Fig. 2- Pressure Relief - Operation
3
Fig. 3- Vacuum Relief - Operation
3
Fig. 4- Pallet Assembly Detail/ Valve
Cross Section
7
LIST OF TABLES
Table 1 - Bolt Torque (Installation)
5
Table 2 - Valve Weights (Maximum)
5
Table 3 - Stem Length (Maintenance)
6
Table 4 - Spare Parts P/N
7
Table 5 - Pallet Assembly Weights
8
Table 6 - Maximum settings
8
Table 7 - Weight Block Dimensions
9
INTRODUCTION:
Pressure and/or vacuum relief valves are
used on liquid storage tanks and other
process vessels or systems to prevent
structural damage due to excess internal
pressure or vacuum.
Storage tanks are pressurized when liquid is
pumped in, compressing the existing vapor or
when rising temperatures cause increased
evaporation or expansion of existing vapor.
Conversely, a vacuum condition may be
created when pumping out or due to falling
temperature. To prevent tank damage, vapor
must be allowed into or out of the tank at
specified pressure/vacuum conditions. The
volume rate of venting depends upon the tank
size, volatility of the tank contents, the
pumping rates and the temperature. Refer to
API Standard 2000 for the procedures to
determine venting requirements.
A relief valve must be carefully maintained by
a qualified valve technician. It should only be
assembled under clean conditions, preferably
in a service shop environment. Carefully read
and understand this manual before installing
or attempting to repair a valve. Groth
Corporation or a factory authorized repair
center offers repair services for all products
manufactured by the Tank Protection
Division.
The table below shows the two different valve
Models covered in this manual and indicates
their Pressure (P) and/or Vacuum (V) relief
capabilities.
Model
P V
Description
1720A
Vent to Header
1760A
Vent to Header
For a list of abbreviations used in this manual,
refer to page 11. For information not
contained in this manual, please contact:
Groth Corporation
13650 N. Promenade Blvd.
Stafford, Texas 77477, USA
(281) 295-6800 (Office)
(281) 295-6999 (Fax)
The nameplate below shows the basic
information that is listed for each relief valve:
26,600
3" X 3" 150# RF
PSV-440
1760A-03-355-TOO
FLOW [SCMH]
% OP
TYPE
SETTING
2 OSI
A CONTINENTAL DISC COMPANY
VAC.
PRESS.
100
100
GROTH
CORPORATION
STAFFORD
TEXAS
USA
117405-10-1
FLANGE:
MD:
TAG:
S/N:
30
15,694
14,500
1 OSI