BAC Document Number: 273 199 5230 Welding
Generator Extended Brazing Gun Service Manual
28/08/2012
Page
14
of
23
For threaded pins the brazing time is the only guideline and this should be set as
close to one and a half second as is reasonably practical. An even fillet of solder
around the base of the pin indicates correct conditions.
When the correct result has been achieved note the position of the power dial on
the generator for future use. This may not necessarily be near the original 40V
240A setting.
Regularly check the gun lift height as detailed in section 5.2, as repeated use can
gradually cause the gun to go out of adjustment.
If the ferrule is not held evenly against the copper lug and is in partial contact then
the arc can escape out of the gap and this will result in the side of the copper lug
burning away.
6.1 ACCEPTANCE CRITERIA OF COMPLETED PIN BRAZE
6.1.1 8mm direct brazing pin and cable lug
•
Mechanical Strength
When the pin braze is completed it should be tested by firmly hitting the
connection twice with a 1KG hammer (do not hit the shank of the cable lug where
the cable is crimped). If there is no movement of the cable lug at the connection
point then the mechanical integrity can be deemed acceptable. Should there be
any movement whatsoever then the connection should be rejected.
•
Electrical Integrity
Using an Ohm meter with a 4 digit resolution, measure the resistance of the pin
braze connection from the cable lug to the pipe. The acceptance criterion is
≤
0.010
Ω
. Note that the test lead resistance should be measured first and
deducted from the absolute resistance measurement.
6.1.2 M8, M10 & M12 threaded brazing pin
•
Mechanical Strength
Threaded pin attachments should be tested by a torque device. For an M8 pin the
torque device should be set to 10 Nm. The threads will fail at 25 Nm, so do not use
excessive force. If there is any movement of the pin up to 10 Nm then the
connection should be rejected.
