Dichloromethane immersion testing machine

product overview
This instrument is used for dichloromethane immersion test of polyvinyl chloride pipes and detection of plastic pipes. The dichloromethane immersion test is an important testing item for PVC-U pipes, used to characterize the degree of plasticization and uniformity of the pipes. The degree of plasticization of the pipes directly affects their long-term hydrostatic performance and has a direct impact on their service life. Different standards have different requirements for the testing conditions of the pipes.
Compliant with standards
GB/T 13256-2007 "Test Method for Dichloromethane Immersion of PVC-U Pipes"
productstructure.
Consists of a constant temperature water bath, sample holder, glass cup, cup holder, and temperature control system
Technical indicators
1. Stainless steel container specification: 400X300X310 (length X width X height unit: mm)
2. Dichloromethane constant temperature: 20 ± 0.5 ℃
3. Instrument temperature control range: 10 ℃ -50 ℃
4. Instrument temperature control accuracy: ± 0.5 ℃
5. Instrument display accuracy: 0.1 ℃
Sampling:
Cut a sample with a length of 160mm from the pipe, perpendicular to the axis of the pipe. The wall thickness of the pipe sample should be greater than the small wall thickness specified in the standard. At one end of the sample, a slope is formed along the entire thickness, and the inclination angle is determined according to the wall thickness of the pipe, as shown in the table below:

When sampling, carefully cut the inclined surface of the sample with a right angle knife as much as possible without causing the material to heat up, then gently polish it with 800 # sandpaper to make the inclined surface smooth and flat, and then carefully clean the inner and outer surfaces of the sample with a dry cloth.
Immersion conditions
1. Put dichloromethane into a glass bottle, filling enough to cover the inclined surface of the sample.
2. Add distilled water to form a water seal layer of at least 20mm.
Experimental steps:
1. Wear gloves when taking and placing the sample during the experiment, and avoid direct contact with the sample by hand.
2. Slowly place the sample holder into the water tank, and weave a spring net on the top of the sample holder according to the size of the sample to fix it. Turn on the instrument power, heating and stirring switches. The water level in the water tank should not be too high to prevent water from flowing into the glass bottle.
3. After maintaining a constant temperature of ± 0.5 ° C to the test temperature, place the glass bottle containing dichloromethane into the cup holder of the sample holder and continue to maintain the constant temperature.
4. After constant temperature, insert the sample into the spring mesh and immerse the cut of the sample completely in dichloromethane for 30 ± 1 minutes. Raise the sample and place it on a water seal layer to remove the surface of the dichloromethane immersion solution, then dry the sample and check for any damage.
5. Calculation of the degree of destruction
6. Calculate the failure rate of the sample according to the standard to evaluate whether the sample is qualified.