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sweeping flame from valve to tube until flux on valve becomes quiet. Avoid excessive heating of
valve.
6. Apply brazing wire or rod at point where tube enters valve socket. Keep flame away from rod
or wire as it is fed into the joint. Move flame back and forth as alloy is drawn into joint. When the
proper temperature is reached, the brazing alloy will flow readily into the capillary gap between
the tube outer wall and valve cup. When the joint is filled, a continuous rim of brazing alloy will be
visible.
The strength of a brazed joint does not vary appreciably with the different brazing materials, but
depends to a large extent upon the maintenance of proper clearance between the outside of the
tube and the valve cup. The interior dimensions of silver brazing valve cups are machined to the
closest tolerances and finished smooth to promote full capillary attraction.
NOTE: Care should be observed in cleaning and in removing residues of the cleaning medium.
Attempting to braze a contaminated or improperly cleaned surface will result in an unsatisfactory
joint. Silver brazing alloys will not flow over or bond to oxides. Oily or greasy surfaces repel fluxes,
leaving bare spots which oxidize and result in voids and inclusions.
7. Allow a solder joint to cool to room temperature – Never shock a solder joint cool with water.
This could damage the integrity of the filler material.
THREADING
Grit, dirt, or any foreign matter accumulated in the pipe can hinder efficient valve operation and
seriously damage vital valve parts. Thoroughly clean pipe internally before assembly. When
threading pipe, gauge pipe threads for size and length to avoid jamming pipe against seat and
disc. Thoroughly clean threaded end to remove any harmful steel or iron deposits.
For a long-term integrity of a joint, use either PTFE tape or pipe compound. Never use both
materials to assemble a threaded joint.
If pipe compound is used, apply sparingly on pipe threads, never on valve threads. Do not allow
any pipe compound into valve body, in order to avoid damage to disc and seat, and otherwise
foul the valve’s sealing performance.
Before installation, check the line of flow through valve, so that valve will function properly.
Close valve completely before installation. Apply an open-end or adjustable wrench on the hex of
the valve adjacent to the pipe joint to be made. Never use a pipe wrench on the valve
connection/hex end, as this can lead to possible distortion of the valve.
Never “wrench through” a valve; i.e., never drive a pipe nipple into one side of a valve in an
attempt to tighten both pipe nipples/connections at one time. Always assemble each threaded
joint by isolating the assembly to a single end of the valve.
After installation of valve, support line; a sagging pipe line can distort valve and cause failure.
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