The sheath is the appearance of the cable. Its appearance requirements are smooth and round, with uniform gloss, no eccentricity (not exceeding the specified deviation), no mechanical damage, flattening, visible debris, bubbles, sand holes, obvious particles, bamboo joints, twisting, etc. In addition to the above quality requirements, the thickness of the sheath also has a certain impact on the quality of the cable. Today, the editor will introduce you to the cable sheath.
About cable sheath
Of course, if the thickness of the sheath is lower than the standard requirement, it is unqualified, but if the thickness exceeds the standard requirement, it is also unqualified.
(1) Shorten the service life. After the cable is laid, it will be energized for a long time, generating heat energy. The allowable operating temperature of the conductor is 70, and the long-term use temperature of polyvinyl chloride should not exceed 65. If the operating temperature rises in summer, these temperatures will be dissipated through the outer sheath, and the thickness of the sheath will increase, which will make it difficult to dissipate heat energy, thereby affecting the service life of the cable. Due to the heating of polyvinyl chloride, the insulation layer undergoes a series of physical and chemical changes, losing its original excellent performance.
(2) There is a problem with the cable structure. If the density of the conductor, insulation, and braid is controlled according to standard requirements, and the appropriate filler is selected to achieve roundness, how can the sheath be squeezed to such a thick thickness?
Here is a brief introduction to cable sheath thickness.
