Tweco 141i Fabricator - Manual (Page 50)

Fabricator 141i
INSTALLATION, OPERATION AND SETUP 3-20 Manual 0-5145
3.18 Flowmeter/ Regulator Operation
With the flowmeter/ regulator connected to cylinder or pipeline, and the adjustment screw/knob fully disengaged,
pressurize as follows:
1. Stand to one side of flowmeter/ regulator and slowly open the cylinder valve. If opened quickly, a sudden
pressure surge may damage internal parts.
2. With valves on downstream equipment closed, adjust flowmeter/ regulator to approximate working pressure.
It is recommended that testing for leaks at the flowmeter/ regulator connection points be carried out using
a suitable leak detection solution or soapy water.
3. Purge air or other unwanted welding grade shielding gas from equipment connected to the flowmeter/
regulator by individually opening then closing the equipment control valves. Complete purging may take
up to ten seconds or more, depending upon the length and size of the hose being purged.
Adjusting Flow Rate
With the flowmeter/ regulator ready for operation, adjust working flow rate as follows:
1. Adjust the gas flow rate. The recommended rate for MIG welding is 15-25 CFH. The recommended rate
for LIFT TIG welding is 10-25 CFH.
NOTE
It may be necessary to re-check the shielding gas flowmeter/ regulator flow rate following the first weld
sequence due to back pressure present within shielding gas hose assembly.
Shutdown
Close cylinder valve whenever the flowmeter/ regulator is not in use. To shut down for extended periods (more
than 30 minutes).
1. Close cylinder or upstream valve tightly.
2. Open downstream equipment valves to drain the lines. Bleed gas into a well ventilated area and away from
any ignition source.
3. After gas is drained completely, disengage adjusting screw and close downstream equipment valves.
4. Before transporting cylinders that are not secured on a cart designed for such purposes, remove flowmeters/
regulators. Put caps on all cylinders that do not have flowmeters/ regulators on them.