Sheath thickness and quality of cable SXXLJT P cable products quality, the advantages and disadvantages, the first characteristic is reflected from the appearance of the product quality, whatever the product, or semi-finished products, must pay attention to appearance quality in the production, the strict control and inspection.
Sheath is the appearance of the cable, the requirement is smooth and rounded appearance, uniform luster, unbiased core (
Shall not exceed the stipulated deviation)
, no mechanical damage, flattening, perception of visible without sundry, bubble, sand holes, clear grain, bamboo, twist, etc.
Sheathed in addition to meet the quality requirements, quality of cable sheath thickness also has certain influence.
Sheath thickness less than standard requirement, of course, is not qualified, but the thickness is beyond standard request, also is not qualified.
For example: cable type for ZRKVVP *.
Mm, the measured average thickness of sheath thickness.
Mm, this types such as GB standard requirements, thickness should be.
Given the unqualified reason has the following points: (
Reduce the service life.
Cable laying, after a long time electricity, electricity will generate heat, allowed working temperature of conductor ℃, polyvinyl chloride (PVC) long-term use of temperature should not be more than ℃, if in the summer, the temperature will rise, the temperature will be through the outer sheath, and sheath thickness increase, the heat is difficult to send out, will affect the service life of the cable, because of polyvinyl chloride (PVC) under the action of heat, has brought a series of physical and chemical changes in the insulating layer, lost the original fine performance, cause the insulation performance is significantly lower, even a short circuit, affecting the normal operation of the unit.
Material performance defects.
Through the thickness of material performance is not to come out, in accordance with the GB standard requirements, it one of the indicators is not up to standard, the flame retardant PVC material, its oxygen index is lower than that.
Cable structure problems.
If conductor, insulation, weave density, according to the standard control, selecting the appropriate filling material make it round, how can such sheath packed so thick?
Increase the difficulty of cable laying.
Now give priority to with bridge or wear tube cable laying, many companies are now in a cable tight, small diameter, has space during the installation process, send out heat, guarantee the cable outer sheath is not damaged, otherwise, bring some difficulties in the construction unit and cable laying.
To sum up, the thickness of sheath shall be in accordance with the standard controls, both for the enterprise to save resources, reduce material consumption, increase profits, and can ensure the quality of cable, create a high quality and low price products.