Groth 1400 - Manual (Page 2)

1
TABLE OF CONTENTS
DESCRIPTION PAGE
Introduction
Pilot Valve Design and Function
Safety Warnings
Shipping, Inspection and Storage
Installation
Maintenance
Disassembly
Assembly
Figures and Tables
Troubleshooting Guide
Customer’s Notes
How to Order
Product Limited Warranty
1
3
3
4
4
5
5
6
6
12
13
14
14
LIST OF FIGURES
1. Tank Installation - Safety
Equipment
2. Groth Nameplate
3. Valve Port Identification
4. Available Seat Configurations
5. Model
1400
6. Model 1420
7. Model 1430
8. Model 1460
2
2
6
7
8
9
10
11
LIST OF TABLES
1. 1400 Series Pilot Operated Valve
Models
2. Body Flange Gasket Dimensions
3. Recommended Min. Torque Values
4. Notes for Figure 4 Thru Figure 7
5. Part no. for Vacuum Pallet Assy.
6. Lubricants – Specifications
7. Troubleshooting
Guide
8. Abbreviations
2
4
4
6
7
12
12
12
NOTE:
For a list of abbreviations used in this manual, refer to Table 8.
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 increasing temperature causes increased
evaporation or expansion of existing vapor.
Conversely, a vacuum may be created when
pumping out or due to decreasing temperature.
To prevent damage, vapor must be allowed to
escape or enter the tank at a specified pressure
or vacuum condition. The volume rate of
venting depends upon the tank size, volatility of
the contents, the pumping rate and the
temperature. See API Standard 2000 for the
procedures to determine venting requirements.
The pilot operated relief valve has two principal
advantages over other types of relief valves:
1) It is bubble tight to set pressure.
2) It achieves the full open position at 10%
above set pressure.
These characteristics permit operating
pressures nearer to the maximum allowable
working pressure of the tank. High operating
pressures reduce evaporation and total venting
volume, thereby reducing product loss and the
cost of processing emissions. A tank may also
have provisions for emergency pressure relief
due to fire exposure and/or inert gas blanketing
of the vapor space. A typical tank installation is
shown in Figure 1 which includes a 1400 Pilot
Operated Pressure/Vacuum Relief Valve, a Gas
Blanketing Regulator (Model 3011) and a 2500
Emergency Pressure Relief Valve which
provides protection under fire or other abnormal
conditions. Groth Corporation manufactures all
of these devices.
A Pilot Operated Valve (POV) 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 attempting to repair a 1400
series POV. Groth Corporation provides repair
services for all products manufactured by the
Groth Products Group.
.