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12 When you close a torch valve, after setting regulator pressure for leak-test or operation, the delivery-pressure gauge hand ”jumps” a few psi. This is normal. If it ”creeps”, however,– that is, moves up slowly but steadily for more than a second or two after the torch valve has been closed – the regulator valve is leaking and should be repaired. While it is true that a slight amount of such creep will have no effect on operation of the torch after it is lighted, it is most unwise to continue to use a regulator that creeps. It should be removed from service and sent to a properly-equipped repair station for overhaul. All regulators are equipped with screens or filters designed to prevent particles of dust from reaching the regulator valve. In many regulators, the filter is located in the inlet nipple itself and is clearly visible. When using such a regulator, make it a practice to look and see that the filter is in place before connecting the regulator to the cylinder. If the filter is missing or if it appears to be clogged with foreign material, replace it before proceeding further. This will take very little time if you will remember to keep a spare filter on hand. NEVER remove a filter until you are prepared to replace it. Torches: If either throttle valve on a welding torch handle will not shut off completely (as revealed by bubbling when the torch tip is placed in water, with pressure in the hose and both valves closed as tightly as possible) you should release all pressure from the system and remove the valve stem assembly from the torch. Wipe clean both the seating surfaces in the torch and on the valve stem. Reassemble and retest. If the valve still will not shut off tightly, either reseating of the valve body or replacement of the valve stem assembly will be required. For reseating, the torch must be sent to a properly-equipped repair station. If the cutting oxygen valve on a cutting torch or cutting attachment will not shut off tight, replacement of the valve seat or valve stem, following instructions supplied by the torch manufacturer, is usually required. If you detect leakage around the valve stem of a torch throttle valve (test must be made after the torch has been lit) you can usually stop the leak by tightening the valve packing nut. Occasionally, it may be necessary to replace a valve packing washer, or replace the complete valve stem assembly. Always follow the instructions supplied by the torch manufacturer. Leakage around the stem of a cutting oxygen valve can usually be repaired on the spot by replacement of a packing washer or O-ring, following instructions of the manufacturer. Do not use substitute materials; use only parts supplied by the manufacturer or his distributor. Continued on next page...