Special cables are cables that have a special purpose and can be used on specific occasions for specific purposes.
Special cables can be resistant to high temperature, acid and alkali, anti-termite, as well as in ships, aircraft, nuclear power plants and other occasions to use the wire and cable. As far as classification is concerned, it does not belong to the same classification method with the categories of electric power, control, computer cables, etc., that is, the cables listed above also contain special cables. General special cables are required to develop enterprise internal control standards.
Special power cable is a kind of power cable used in special working environment, its internal structure, production process relative to the ordinary power cable is more complex, more durable. Now there is no uniform definition of special power cable, special power cable does not require CCC mandatory certification, but the choice of certification. General special power cable inspection scale are developed by the manufacturer, the production of cables in accordance with the national GB scale. Special power cables in the field of application is now more and more extensive.
Speciality cables are usually used in special areas where their role is special. For example, high temperature resistance, strong acid and alkali, anti-termite and other functions are higher.
Among them, high temperature resistant wire and cable are mainly used in energy development, steel, aerospace, oil exploration and metal smelting. Low inductance cable has good heat dissipation, high cooling water flow, no blockage and current limitation.
Low noise cables are mainly used in medicine, industry, national defence and other fields that require small signal measurement to detect bass. There are functional wire and cable and new green cable.
High temperature resistant
Aerospace, rolling stock, energy, iron and steel, non-ferrous metal smelting, oil mining, electrical machinery, construction and other fields need to use high temperature resistant wire and cable. Long-term continuous operating temperature of 125 degrees, 135 degrees, 150 degrees, 180 degrees, 200 degrees, 250 degrees and 250 degrees above the high-temperature wire and cable, commonly used irradiated cross-linked polyolefin, silicone rubber, fluorine resin, polyimide, mica, magnesium oxide and other wires and cables. Now introduced; two new high temperature wire and cable.
With excellent heat resistance, physical and mechanical properties, electrical insulation properties, extrusion moulding, especially with continuous use at high temperatures and rapid changes in temperature environment can still maintain stable performance and other outstanding advantages: heat distortion temperature of 200-220 degrees, continuous use of the temperature of 180-200 degrees, the UL temperature index of 180 degrees; can withstand 150-160 degrees hot water or steam, in high temperature It is not subject to acid and alkali erosion at high temperature; modulus of elasticity is almost unchanged at -100-200 degrees, especially above 100 degrees, which is better than any kind of thermoplastic resin; coefficient of linear expansion is small and its temperature dependence is small; it has non-toxicity, which is recognized by the US FDA, and also conforms to the requirements of the Announcement of the Ministry of Health, Labour and Welfare of Japan No. 434 and No. 178; it has self-extinguishing property, and it is excellent flame-retardant without any flame-retardant additive. It is self-extinguishing and has excellent flame retardant without adding any flame retardant, and can reach UL94V-0 grade (0.46mm).
Polyester ether ketone is a super heat-resistant thermoplastic resin. Long-term continuous use temperature of 250 degrees, UL temperature index of 250 degrees.
PEEK is a flexible resin, and good creep resistance. And self-extinguishing, without adding any flame retardant up to UL94V-1 level (thickness of 0.3mm), 94V-0 (thickness of 1.5mm), 94V-5 (thickness of 3.2mm) requirements.
There is a difference between strong and weak power, and here we introduce a low inductance cable for strong power. This cable with heat dissipation device for all kinds of contact welding machine, arc welding machine and pneumatic welding clamp connected between the new water-cooled low-inductive cable, with a simple and reasonable structure, cooling water flow, will not form a blockage blocking and limiting the phenomenon of heat dissipation is good, long service life and so on.
This new type of low-sensitivity cable also includes cable and cable ends with solidly mounted joints, and the cable is also composed of a positive cable core and negative cable core installed in the outer hose. As such low-sensitivity cable is generally used for the voltage of 25-50V, current in the 7000-12000A between the occasion, the cooling water in the cable in the short-circuit conductive phenomenon is basically negligible, so in this low-sensitivity cable does not use the isolation of the positive cable core and the negative cable core of the rubber hose, just set up a special cross-section of the spoke (commonly known as "Plum Blossom Core"). Plum blossom core" shape) of the core frame, its "wheel centre" and adjacent "spokes" of the space enclosed between in the axial direction, that is, the formation of longitudinal grooves, longitudinal grooves on the core frame and the cable is configured with the same number of the total number of positive cores, the cable part is based on the positive core and the negative core. The cable part is to positive cable core and negative cable core were resting on the core frame of the longitudinal grooves in the device outside the hose composition. Positive cable core and negative cable core of the two ends of the head were the same pole collection of bundles clamped in the core clamp, and then solidly installed in the connector, the cable end of the outer hose set in the connector at the end of the end of the part, and with the set of the outer hose outside of the tightening hoop tight sealing.
In the bending, vibration, shock, temperature changes and other external factors, the cable itself produces a pulse signal less than 5mV of the cable is called low-noise cable, also known as anti-vibration instrumentation cable. It is used for the measurement of tiny signals in many fields such as industry, medicine and defence. There are polyethylene insulated low-noise cables, F46 insulated low-noise cables, irradiation-resistant low-noise cables, low capacitance low-noise cables, hydrophone cables, watertight low-noise cables, and many other types of cables with specifications.
The causes of noise in cables are: (1) molecular friction within the medium itself; (2) changes in the capacitance of the cable; (3) piezoelectric effect of the cable medium; and (4) friction between the conductor and the medium in the cable generates a charge, i.e., when the contact between the conductor and the insulation is broken generates a separation of the charge.
In the polyethylene insulation surface extrusion of a thin layer of semi-conducting (thickness 0.20-0.30mm) of low-noise cables have been rapid development, the noise value of 2-3mV, for low-noise cables working at 400 degrees can be solved by using high-temperature-resistant semi-conducting fibre winding, the noise of the noise up to 5mV.
Secondly, it is also a link that should not be underestimated, that is, the installation of the cable acceptance check to see if there are omissions.
1. First, we ask the user to acceptance check to see whether the cable indicates any breakage, and the construction personnel with a multimeter to test the resistance and insulation resistance of each cable, in order to confirm whether the cable resistance is normal, the insulation is normal, be recorded.