Suitable for railways and other communications with copper-core polyethylene foam insulation and metal sets of long-distance symmetrical communication cable. Quad digital transmission group is applied to 4-6 sets of PCM group communication for 1MHz. High-frequency quad group used to carrier communication 156KMz. Low-frequency quad used to the section of the sound the letter. Signal, twist and quad signal group used for line maintenance and signal remote monitoring system. Product standard in accordance with TB／T1478－83
Cable laying in permafrost, the using environmental temperature of cable is +60℃～-20℃, and laying temperature is not less than -5℃.
Bending radius of cable is 30 times of metal sleeve diameter, or 25 times of outer diameter.
It should be avoided mechanical damage (Smashing, folding, stress, and etc.) in transport and laying.
Cable laying continuation Pa Tau, should be moisture-proof, water infiltration within the cable, and in the head should be to prevent the burn wire core insulation.
The cable should maintain pressure, filled with dry air or nitrogen, the pressure for the aluminum-sheathed cables 5-20N/cm2.
No cream filling time, the cable should ensure the continuity of the continuation at the filler, ensure the cable block water performance.