The laboratory of Zhejiang Qichao Cable Co., Ltd. has purchased an anti cracking testing device produced by Suzhou Kaitel Instrument to meet the requirements of testing the flame retardant performance of cables in accordance with the national standard 18380.
Zhejiang Qichao Cable Co., Ltd. was founded in October 2009 with a registered capital of 76.75 million yuan. It is located in Quzhou City, the marginal central city of Zhejiang, Fujian, Jiangxi, and Anhui provinces. It is a large-scale wire and cable manufacturing enterprise in western Zhejiang and a key industrial enterprise in Quzhou City. The company is a specialized cable production enterprise that integrates research and development, production, sales, and service. It mainly produces four categories of cable products: 35KV and below power cables, electrical equipment wires and cables, special cables, bare wires, and bare conductor products. The company's products are widely used in industries such as power transmission, transportation, energy, petrochemicals, and urban construction, and have obtained national industrial product production licenses. The company has been honored with titles such as "Quzhou Integrity Private Enterprise", "Quzhou Third level Safety Standardization Standard Enterprise", and "Quzhou Labor Security Credit * Enterprise in 2017". In early 2018, the company was awarded the "Quzhou Mayor's Special Award for 2017".
The KTR011 anti cracking test device we produce is suitable for winding PVC wires and cables before cracking tests under high temperature conditions. Complies with the requirements of GB/T2951.31.9-2008 and GB/T2951.6-1997 standards (Test Method for Polyvinyl Chloride Mixtures of Cables and Optical Cables).
Sample test:
Each sample should be tightly wound in a spiral shape on the test rod at ambient temperature and fixed at both ends.
The diameter of the test rod and the number of winding turns are specified as follows:
a) The diameter and number of turns of the test rod for the sample, flat cable or flexible wire prepared according to item 1.2a) in the instruction manual are specified in Table 1. The diameter of the test rod should be selected according to its short axis size, and the short axis should be perpendicular to the test rod during winding. The sample wrapped around the test rod should be placed in an air oven preheated to the test temperature specified in the relevant cable product standard. If the cable standard does not specify it, it should be preheated to (150 ± 3) 0C, and the sample should be kept at the specified temperature for 1 hour.
After the heating is completed, take out the sample from the oven and check the sample still on the test rod after it reaches the approximate ambient temperature.
Evaluation of experimental results
When examined with normal or corrected vision without a magnifying glass, the specimen should crack.
Sheath thermal shock test
sampling
Two cable samples of appropriate length should be taken from each test sheath, with two samples taken at least 1 meter apart. If there is an outer protective layer, it should be removed.
sample preparation
a) For sheaths with an outer diameter not exceeding 12.5mm, each sample should be a section of cable, except for polyethylene insulated and polyethylene sheathed cables.
b) For sheaths with an outer diameter exceeding 12.5mm and a thickness not exceeding 5.0mm, as well as sheaths of polyethylene insulated cables, each sample should be taken from a narrow strip on the sheath, with a width of at least 1.5 times the thickness of the sheath but not less than 4mm. The narrow strip should be cut along the axis direction of the cable.
c) For sheaths with an outer diameter exceeding 12.5mm and a thickness exceeding 5.0mm, each sample should be a narrow strip cut according to item b), and then ground or cut (to avoid overheating) on the outer surface of the narrow strip to a thickness of (4.0-5.0mm). The thickness should be measured at the thicker part of the narrow strip, and the width of the narrow strip should be at least 1.5 times the thickness.
d) For flat cables, if the width of the cable does not exceed 12.5mm, each sample should be a complete section of the cable. If the cable width exceeds 12.5mm, each sample should be a narrow strip cut from the sheath as specified in b).
Sample winding
Each sample should be tightly wound in a spiral shape on the test rod at ambient temperature, with both ends fixed.
The diameter and number of turns of the test specimen prepared according to item 2.2a) of the instruction manual, as well as the flat cable with a width not exceeding 12.5mm according to item 2.2d) of the instruction manual, should be in accordance with the provisions of item 1.3a) of the instruction manual. The diameter of the test rod should be selected according to the short axis size of the cable, and the short axis should be perpendicular to the test rod during winding.
The test specimens prepared according to instructions 2.2a) and 2.2c), as well as flat cables with a width exceeding 12.5mm as specified in instructions 2.2d), should have the diameter of the test rod and the number of winding turns as specified in section 1.3b). In this case, the inner surface of the specimen should be in contact with the test bar.
Heating and inspection
According to the provisions of 1.4 in the manual, the evaluation of the test results shall be determined according to 1.5 in the manual!