Laboratory

The HAWLE laboratory continuously performs various tests to ensure quality workmanship. Raw materials are checked for their suitability, samples are taken at random and checked during each production step and finished goods are subject to periodic tests, audit and review. Both destructive and non-destructive procedures are applied in order to yield those test results needed to determine the product’s quality level and carried out according to HAWLE test methods by specially trained and experienced staff. All test results are documented and corrective measures are initiated if necessary.

Some of the tests used are:

laboratory_hawle_4_en 100% pressure testing corrosion test practice test burst test tensile tests

Burst test

Hawle technicians carry out product burst tests under experimental conditions in special test facilities equipped with accident protection.

Testing pressure 24 bar
Pipe burst at 61,5 bar
Grip ring markings after the test

For example by attaching end cap SYSTEM 2000 fittings to one end of DN 80 PE pipe and a blank flange PN 16 at the other, the behavioural characteristics of the pipe grip under increasing pressure can be studied.

 

All Hawle products must withstand the minimum of 1.5 times the specified pressure. For example a PN 16 rated product must withstand the equivalent of 24 bar pressure according to the requirements given in EN 12266.

 

The burst test experiment is usually performed with water. 10 bars is the initial pressure and then continuously increased until the load reaching pressure specified in the norm is achieved.

 

The pressure is steadily increased until the failure of one component is observed. It is reassuring to see that the Hawle product never fails under this condition because this demonstration clearly shows that the grip ring effectively holds on to the pipe. After 4 minutes and at a pressure of 61.5 bar, the PE pipe shows typical elongation behaviour and ends up as a bubble instead of escaping the fitting.

 

Furthermore, upon subsequent inspection of the PE pipe one can clearly see the remarkable grip ring performance. There is no damage to the pipe surface where the grip ring was holding on to the pipe. Thus the burst test is evidence that the grip ring will hold on to the pipe during pipe bursting pressure circumstances.