Operating personnel should become familiar with characteristic opening/closing action of the valve. Should operation ever become sluggish, remove valve from service and contact North American for replacement recommendations. ANY VALVE USED FOR AUTOMATIC SHUTOFF SHOULD BE CHECKED ON A REGULAR SCHEDULE. NORTH AMERICAN RECOMMENDS CYCLING (CLOSING AND OPENING) 1518 OR 1519 VALVES AS SPECIFIED IN NFPA 86. MORE FREQUENT CHECKING AND CYCLING IS REQUIRED IF THE FUEL GAS IS DIRTY OR IF THE VALVE IS LOCATED INADVERSE (CORROSIVE, DIRTY, ETC.) ENVIRONMENT . OPERATION AND TESTING WARNING: Automatic Shutoff Valves, such as North American's 1518 and 1519 series, are furnished for either standard or non-standard fuel service, a maximum pressure, and specific power supply. These and other specifications appear on the main nameplate of each valve. Read them carefully to be sure they apply to your application. After correct installation and pre-testing, regular operational test including inspection and maintenance are critical to continued good valve operation. When used on dirty fuels, such as coke oven or digester gas, valves should be TESTED for leaks daily. Valves that control clean, dry natural gas might be TESTED less frequently. It is recommended valves be CYCLED regularly as described previously under "PRE- START TESTING". Frequency of these procedures is best determined by user's experience with the specific fuel and the nature and degree of system controls . If there are any doubts about an appropriate preventive-maintenance schedule, contact North American for assistance. Automatic Shutoff Valves are not intended for use as permanent fuel shutoff devices. An approved manual tight-shutoff valve must be installed as the permanent shutoff valve (located per Item 1 Fig. 1). During combustion downtimes, this valve MUST be closed.
IF THESE VALVES ARE RESOLD, IT IS YOUR OBLIGATION TO ADVISE THE ULTIMATE USER OF THESE CRITICAL REQUIREMENTS.
LEAK TESTING Modern gas train design allows a user to perform leak tests on main and blocking valves. Required by NFPA 86, and insurance underwriters, this fixed provision must be on all existing and new gas trains to facilitate periodic leak testing. Proper test procedures should not only check for leaks, but also allow a basic check of the flame safeguard and limit monitoring system, proving shutdown on loss of flame or through faults in other safety interlocks.
Inspection, testing, and maintenance should be done on a regular scheduled basis determined by the user.
Operators should be aware of and carefully observe characteristic opening/closing action of the valves. IF OPERATION EVER APPEARS SLUGGISH OR ABNORMAL IN ANY WAY, REMOVE VALVE FROM SERVICE.
Do NOT lubricate any parts of the valve.
Physical inspection of the valve should include assurance that the NEMA-4 integrity of the upper housing is maintained. Make sure all top and sideplate screws and gaskets are intact, and that electrical conduit is installed in a manner that prevents water or condensation from entering housing.
INSURE THAT JUMPER WIRES, OR ANY OTHER DEVICES, ARE NOT USED TO HOLD A VALVE OPEN.
Instructions 1518/1519 Page 5
Made with FlippingBook flipbook maker