Mounting of Specimen
The test pipe that is chosen for the test needs to correspond in diameter with the specimen to be tested. It can however be a little smaller. This ensures an air-tight fitting and alignment of the specimen onto the test pipe.
The specimen has to be slid fully onto the pipe from the wireless end of pipe.
Minor air gaps between test pipe and specimen can be removed by wrapping the specimen with thin gauze bandage if the specimen is elastic.
Afterwards the outer diameter of the specimen has to be evaluated (e.g. according to EN ISO 8497 section 8.5 by using a highly flexible steel tape with an error of ± 0,5%).
The outer test sheath that is chosen needs to match the size of the specimen in width. After spreading the sheath onto the working platform the test pipe with the specimen needs to be placed onto the sheath horizontally. All connecting wires should be on one side.
The sheath must be wrapped tightly without any air gaps around the specimen. Strips of sticky tape are used to fix the sheath onto the specimen, starting in the middle. Be careful not to exert pressure onto the specimen, as this might compress the specimen resulting in test error for the diameter.
The sheath is then fully and firmly fixed by strips of sticky tape.
Afterwards a rubber mat 2 mm in thickness and twice the size of the sheath is wrapped around the sheath. The specimen in the sheath is rolled into the rubber mat. The mat is then firmly fixed by using sticky tape strips again.
Finally the test assembly is fully and firmly wrapped by a gauze bandage.
After connecting all four wires, the test arrangement is inserted into the test chamber where it will rest on bearing nooks on the right and left hand wall.
The test chamber is then shut by putting the top cover on. Now you can switch on the tool and start the test process.
