Wire and cable thermal deformation testing machine (six group type)

KTR012DWire and cable thermal deformation testing machine (six group type)

1Thermal deformation test for wires and cablesmachine(Six group formula)Introduction:

This machine is used to test the degree of thermal deformation of materials such as plastics and wire sheaths. At a specific temperature, place the specimen freely in the testing machine for 30 minutes, then clamp it between parallel plates of the machine, apply the specified load, and place it at the same temperature for another 30 minutes. Measure the thickness difference before and after heating with a gauge, and divide the thickness difference by the thickness before heating to obtain the deformation rate. Complies with the GB/T8815-2008 standard for flexible polyvinyl chloride plastics for wires and cables.

IIThermal deformation test for wires and cablesmachine(Six group formula)Main parameters:

1. Experimental setup: 6 sets;

2. Sample: a circular piece with a diameter of 12mm or a square piece with a side length of 12mm, with a thickness of (1.25 ± 0.15) mm;

3. The device consists of a frame, a cylindrical heavy hammer, a cylindrical pressure rod, and a horizontal bracket;

4. Cylindrical heavy hammer: The total downward pressure is (3.5 ± 0.02) N;

5. Cylindrical pressure rod: diameter of (3.15 ± 0.03) mm.

IIIThermal deformation test for wires and cablesmachine(Six group formula)Test procedure (refer to GB/T8815-2008)

1. Cut the sample: The sample should be a circular piece with a diameter of 12mm or a square piece with a side length of 12mm, with a thickness of (1.25 ± 0.15) mm.

2. Measure the thickness of the area to be pressurized at room temperature. If a dial gauge is used, there should be appropriately sized contact points and only slight pressure should be applied to the sample.

3. Heat treatment: Separate the testing device and the sample and place them in an oven without vibration. The temperature inside the oven should be maintained at (120 ± 2) ℃ for 1 hour.

4. After heat treatment, conduct a pressure test on the sample using a cylindrical pressure bar.

5. Place it in an oven and maintain a constant temperature of (120 ± 2) ℃ for 1 hour.

6. After the time is up, remove the entire experimental apparatus from the oven, cool it at room temperature for 1 hour, remove the sample, and immediately measure the thickness of the deformed part of the sample using the instrument used at the beginning of the experiment.

4Thermal deformation test for wires and cablesmachine(Six group formula)Calculation and evaluation of experimental results

The thermal deformation Dt is calculated in% according to equation (1):

Dt=(d0-d)/d0

Where:

D0- Original thickness of the sample, measured in millimeters (mm);

D - The thickness of the specimen after testing, measured in millimeters (mm).

The arithmetic mean of two samples is taken as the experimental result. If the deviation between two test results is more than 10% of their average value, the sample is invalid and a new sample should be taken.

Note:

When this device is placed in an oven for heat treatment, it should be kept horizontal. When it is taken out of the oven for cooling, it should be placed on a horizontal test bench;

2. Pay attention to high temperatures during operation and have protective tools to avoid being scalded;

3. Pressure devices should be handled with care and kept clean.