Modern electronic countermeasures and the information in the war against ability strong and the weak is the key to determine success or failure. The third generation of nuclear weapons, main is to improve the ability of producing stronger electromagnetic pulse energy, to destroy the opponent's command, control, communications, intelligence information system. Improvement of military electronic equipment of nuclear electromagnetic pulse resistance measures will directly related to the vitality of defense weapons. Look at how to improve the performance of resistance to nuclear electromagnetic pulse cable at the same time, simplify the structure of cable and weight increase flexibility and reduce manufacturing costs, expand applicable scope, the cable for the China's national defense weapons by nuclear electromagnetic pulse radiation still can guarantee fast mobile operations ability, has the important practical significance.
At present domestic nuclear electromagnetic pulse resistance of cable widely used multilayer metal and metal film around the package block combination, due to the limited material and structure, has certain defects, can't meet the modern high-tech weapons to cable higher nuclear electromagnetic pulse resistance requirements and a wider scope of application. And newest nuclear electromagnetic pulse resistance soft cable, has simple structure, good flexibility, light weight, higher nuclear electromagnetic pulse resistance, effectively improve the weapon system performance and reliability.
A typical performance, product requirements:
(1) the operating temperature of the cable: - 40 ~ 105 ℃
(2) the cable nuclear electromagnetic pulse resistance. Cable in nuclear electromagnetic pulse field strength of 50 kv/m, rising 2.5 ns, half high width of 23 ns, spectrum under the condition of no greater than 100 MHZ, its shielding effectiveness is not less than 70 db.
(3) the whole tensile performance. Cable should be at room temperature can withstand the weight of 100 m pulling force without damage. After test specimens subjected to power frequency ac 50 hz, 1000 v voltage (RMS), 2 min not breakdown.
(4) the bending and twisting around
Bending --, under normal temperature, the cable should be able to withstand repeated 100 times and cycle, perception of visible sheath surface should not have crack, after test specimen subjected to power frequency ac 50 hz, 1000 v voltage (RMS), 2 min not breakdown.
Twisted around sex --, under normal temperature, the cable should be able to withstand torsional around 20, perception of visible sheath surface should not have crack, after test specimen subjected to power frequency ac 50 hz, 1000 v voltage (RMS), 2 min not breakdown.
(5) wear resistance. Blow grind number 300 times, after test any inner sheath are exposed as a failure.
(6) cable bending test 2000 times. Under normal temperature, the cable withstand repeated bending test after 2000 times, the surface of the sheath perception of visible cracks, there should be no printing discernible, by conduction test. Withstand voltage test (2000 v, 2 min) no breakdown.
(7) of cable should be prescribed by GJB150.11 smoke 96 h test, no corrosion.
Second, the design idea: improve the shielding effectiveness is a quite complicated problem, not only have electric field component of the electromagnetic wave, and magnetic field component, designed with high permeability and high conductivity are equally important. Due to the low frequency electromagnetic wave is better than high frequency electromagnetic wave has a strong magnetic field component, therefore, for low frequency electromagnetic interference, shielding materials of permeability is far more important than when high frequency, to give priority to choose high magnetic permeability of materials. High-frequency electromagnetic interference should be taken into account the main electric components, choose low surface transfer impedance of high conductivity materials. Thus, for the high requirement of cable, it is necessary to use multilayer shielding, so as to fundamentally solve the problem of high frequency shielding effectiveness is low. Nuclear electromagnetic pulse resistance cable shielding layer at home and abroad generally USES a layer of soft magnetic alloy belt and multilayer metal band around the package and multilayer wire weaving, the cable is the stiff, complicated structure, it is not easy bending faults; Field use often appear soft magnetic alloy with scratches or broken wire core, cause the loss of cable short circuit or nuclear electromagnetic pulse resistance, soft, can not meet the field of motor cable weight requirements. To solve this problem, the winding and shielding, weaving to cross combination way, and for the first time with copper and nickel alloy of cloth and cloth belt winding and iron nickel alloy instead of soft magnetic alloy of metal around the package material. Mainly by the conductor, insulation, cable, composite shielding layer, sheath, described composite shield by "copper and nickel alloy cloth belt + tin plated copper knitting with + + ptfe microporous iron-nickel cloth belt + nickel plated copper wire weaving".