Guidelines for care & Use of Dry Solvent Stills [Example]

Test for leaks anywhere by squirting soapy water (such as “Snoop” brand name solution) onto the fitting. If
a steady stream of bubbles appears, loosen the fitting, tilt the angle of the regulator slightly, and retighten.
The leak would not happen unless scratches from both surfaces coincide – changing the angle of metal-tometal
contact lessens the probability of matching microscratches.
Teflon tape used on the attachment fitting between regulator and cylinder does nothing to improve
the seal between the surfaces of the “ball and socket” joint. Hence, tape should be avoided, except for gas
line fittings which employ thread only, such as regulator outlets, or needle valves on the outlet side of the
regulator, or gas line connectors further down the gas line, away from the regulator and cylinder. Likewise,
teflon tape can be used to tighten pipe (NPT) thread fittings in gas lines, since these tapered thread fittings
are constructed so as to seal at the threaded metal surfaces. Swagelok fittings seal when the front and back
ferrules within the fitting press against each other – which cannot happen if they are separated by teflon
tape. DO NOT use teflon tape on Swagelok fittings.
The Lab Manager has a useful book entitled “Swagelok Tube Fitter’s Manual” which you are
welcome to consult whenever you wish. The following web site list very good directions for working with
swagelok fittings: http://www.swagelok.com/ and click on “Products”, “Catalogs”, “Fittings-Tube”,
“Connects tubing to tubing”, and, finally, any one of the remaining options, such as “Reducing Union
Tees”, and on to “Assembly/Installation” PDF files, such as those for adapters/ reducers “for one-and-aquarter
inch & 25 mm and larger”sizes.
See also the following helpful procedures if your lab has need of them:
"Lightup and shut down procedure for oxygen fuel torch," National Welders Supply Company,
Inc., PO Box 31007, Charlotte, NC 28231, phone # 1-800-866-4422. [located in the stockroom hardcopy
of the CHP, room # 110]
"Atomic Absorption Acetylene: Recommendation for Use," National Welders Supply Company,
Inc., PO Box 31007, Charlotte, NC 28231, phone # 1-800-866-4422, Company memo from Gary Stiles to
district managers. [located in the stockroom hardcopy of the CHP, room # 110]
"Technical Information Bulletin #AL-167, Instructions for Using the Calibration-Gas Cylinder,"
Aldrich Chemical Company, 1001 West Saint Paul Ave., Milwaukee, Wisconsin 53233, phone # 1-800-
558-9160. [located in the stockroom hardcopy of the CHP, room # 110]
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