Groth 3011L - Manual (Page 5)

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GENERAL SAFETY INSTRUCTIONS
This section is intended as an overview of safety guidelines that should be followed during the installation, operation and
maintenance of the Groth model 3011L, & 3041L, 3011H & 3041H, 3011HP & 3041HP Blanket Gas Regulators. To understand
the context of these warnings and instructions, read and understand this complete manual.
The blanket gas regulator is one of the principal protection devices typically installed on a product storage tank. It is a precision
regulator that is designed to maintain a positive pressure on the tank. This will prevent product loss or contamination from
atmospheric air when pumping liquid out or when the stored fluid cools.
The blanket gas regulator should not be used as a substitute for a vacuum relief valve. An interruption in the blanket gas supply
could cause tank failure.
SAFETY WARNINGS
IN THE EVENT OF AN ACTUATOR OR PISTON DIAPHRAGM FAILURE, THE REGULATOR WILL FAIL IN THE OPEN
POSITION. GAS FLOW WILL NOT BE SHUT OFF. EMERGENCY AND OR PRESSURE/VACUUM RELIEF VALVES MUST BE
SIZED TO INCLUDE BLANKET GAS REGULATOR CAPACITY IN ADDITION TO NORMAL AND EMERGENCY VENTING
REQUIREMENTS.
IN THE EVENT OF BLANKET GAS SUPPLY FAILURE, THE REGULATOR WILL NOT PROTECT THE TANK FROM AN
EXCESS VACUUM CONDITION. BLANKET GAS SUPPLY FAILURE SHOULD BE CONSIDERED IN THE SIZING,
SELECTION AND SETTING OF PRESSURE/VACUUM RELIEF VALVES.
BLANKET GAS REGULATOR FLOW CAPACITY IS BASED ON A KNOWN SUPPLY PRESSURE AND A PROPERLY SIZED
GAS DISTRIBUTION SYSTEM.
ALL SUPPLY PIPING MUST BE FREE OF WELD SLAG AND OTHER DEBRIS BEFORE INSTALLING THE BLANKET GAS
REGULATOR. IF WELD SLAG OR DEBRIS FLOWS THROUGH THE REGULATOR THERE IS A HIGH POTENTIAL FOR
SEATING SURFACE AND O-RING DAMAGE. THIS TYPE OF DAMAGE WILL CAUSE THE REGULATOR TO CONSTANTLY
FLOW BLANKETING GAS TO THE TANK. TO PREVENT DAMAGE FROM WELD SLAG OR DEBRIS CONSIDER
INSTALLING AN UPSTREAM FILTER OR STRAINER. AN ENGINEERING ANALYSIS MUST BE PERFORMED TO
EVALUATE THE EFFECT THESE DEVICES MAY HAVE ON THE BLANKET GAS REGULATOR FLOW CAPACITY.
THE REGULATOR IS NORMALLY FACTORY SET AT THE DESIRED SET PRESSURE. THE SPRING RANGE IS STAMPED
ON THE NAMEPLATE. DO NOT ATTEMPT TO RE-ADJUST THE SET PRESSURE BEYOND THE LIMITS SPECIFIED IN
TABLE 3.
THE REGULATOR IS TO BE CONNECTED TO THE TANK OR VESSEL WITH A MINIMUM 0.31" ID TUBING SENSE LINE.
THIS LINE MUST BE KEPT OPEN AND UNOBSTRUCTED TO ENSURE THAT THE REGULATOR SENSES THE ACTUAL
TANK PRESSURE. LONG SENSE LINES MAY REQUIRE A LARGER DIAMETER AND CARE MUST BE TAKEN TO ASSURE
THAT THE LINE IS SELF-DRAINING. FOR SOME APPLICATIONS, A NITROGEN PURGE MAY BE REQUIRED TO ENSURE
THAT THIS LINE REMAINS OPEN. CONSULT FACTORY FOR RECOMMENDATIONS.
DO NOT ATTEMPT TO REMOVE THE REGULATOR FROM THE LINE OR PERFORM FIELD REPAIRS IN LINE WITHOUT
FIRST ISOLATING THE REGULATOR FROM BOTH THE TANK AND THE SUPPLY GAS LINE. BLEED ALL PRESSURE
BEFORE REMOVING THE SPRING BONNET OR THE FLOW ORIFICE LOCKING SCREW, OR OPENING UP THE
ACTUATOR HOUSINGS.
NOTE THE ORIFICE SLEEVE POSITION WHEN DISASSEMBLING THE REGULATOR. IT WAS FACTORY SET ACCORDING
TO THE FLOW REQUIREMENTS LISTED ON THE ORDER AND MUST BE RE-INSTALLED IN THE SAME POSITION TO
ENSURE THE CORRECT FLOW.
THE REGULATOR BODY AND ACTUATOR HOUSING ARE EXPOSED TO PROCESS VAPORS. OBSERVE ALL SAFETY
PRECAUTIONS AS SPECIFIED ON THE MATERIAL SAFETY DATA SHEET FOR THE PRODUCTS THAT ARE IN THE TANK.
THE VENTS ON THE SPRING BONNET AND ACTUATOR HOUSING MUST BE CLEAN AND OPEN TO THE ATMOSPHERE
AND SHOULD BE INSPECTED PERIODICALLY.
THE RECOMMENDED SET PRESSURE RANGE OF THE REGULATOR SPRING IS STAMPED ON THE NAMEPLATE.
NEVER ADJUST A SPRING FOR A SET PRESSURE BEYOND ITS DESIGN RANGE AS SPECIFIED IN TABLE 3.
EXCEEDING THE SPRING UPPER LIMIT MAY COMPRESS THE SPRING TO ITS SOLID HEIGHT, AND PREVENT THE
REGULATOR FROM CLOSING. SETTING IT BELOW THE LOWER LIMIT MAY PREVENT THE REGULATOR FROM
OPENING FULLY AT THE REQUIRED PRESSURE.