How to test the welding joints?
Make sure that the welding of the two surfaces is correct by the following steps:
First: Air Pressure Test:
• Close the welding tube from one of its terminals.
• Push air into the tube with 2 bars pressure for 5 min.
• Air pressure is monitored during this period & the welding is correct when air pressure is stable
during the whole period.
Second: Vacuum Box:
• The tested surface is painted with liquid soup.
• The vacuum box is put inside the testing zone; it has air vacuum pump & pressure counter.
• The air vacuum pump is operated to the pressure of 5 atmospheric pressure for 10 sec
• When the vacuum pressure is fixed during this period , this is a sign that the welding is correct
Third: Holiday Detection apparatus
• This method is used to reveal any surface puncture resulted from transportation or handling or etc.
• The apparatus passes an electrostatic charge on the PE surface for the welded zones. If there
is a small surface puncture the apparatus makes an alarm either sound or light meaning that the
electric voltage of the apparatus had a decrease because of the charge leakage to the ground
through the puncture.
• The defect can easily be detected and fixed.