无卤低烟阻燃钢带铠装电缆护套应力开裂的探讨

Investigation of the Stress Cracking in the Sheath of Low Smoke HFFR Cables with Steel Tape Armour

探讨了无卤低烟阻燃铠装电缆护套应力开裂的机理,提出了防止护套应力开裂的方法,在电缆的双层间隙的绕包铠装和无卤低烟阻燃聚烯烃护套之间含有缓冲层,用于消除电缆弯曲时在钢带间隙处外护套上形成的应力集中现象,保护护套不受双层钢带铠装的影响而开裂,因而提高电缆使用寿命和可靠性。

The mechanism of the stress cracking in the sheath of low smoke HFFR cables with steel tape armour was investigated. A method to prevent the sheath stress cracking was proposed. A bedding to eliminate cable bending was applied between the double sparsely wrapped tape armour and the low smoke HFFR sheath so that stress concentration is formed both between tapes and on the sheath. In this way, the sheath can be protected from being cracked by the double tape armour and the cable service life and reliability can be improved.