对于单芯电缆来说,在电缆的绝缘屏蔽层上绕包半导电阻水带,在金属屏蔽层外面绕包普通阻水带,然后挤包外护套,外护套材料可以是普通的PVC,也可采用具有径向阻水功能的HDPE材料等,可视电缆其它性能要求而定。对于三芯电缆,则为了保证金属屏蔽的充分接触,只在绝缘屏蔽外面绕包单导电阻水带,金属屏蔽外不再绕阻水带,视防水性能要求的高低,填充可采用普通填充或阻水填充,内衬层及外护套材料同单芯电缆中所述。
For single-core cables, in the cable insulation shield semi-conductive water blocking tape wrapped on the outside metal shield wrapped ordinary waterproof tape, and then extruded outer jacket,outer sheath material may be ordinary PVC may also be used HDPE material having a water-blocking function of the radial and the like, the visual properties of the cable other requirements. For three-core cable, the metal shield in order to ensure full access only outside wrapped in insulation shield a single conductive water blocking tape, metal shielding around the outside is no longer waterproof tape, waterproof performance requirements depending on the level of the ordinary can be filled or filled water blocking filling, inner liner and the outer jacket material of the same single cable.
在外护套或内衬层的内部纵包铝塑复合带层作为防水层,对于绝缘电缆来说,则主要采用金属护层使电缆达到防水要求,金属护层的最大特点是具有完全不透过性,故具有金属护套的电缆具有非常好的径向阻水性能。
Liner inside the outer jacket or vertical bag plastic composite tape layer as a waterproof layer, for insulated cables, it is mainly a metal sheath of the cable reaches water requirements, the biggest feature is a metal sheath having a completely impermeable cable resistance, it has a metal sheath has a very good radial water blocking performance.
电缆的防水方式一般分为纵向阻水和径向径水两种。纵向阻水一般常用的有阻水纱、阻水粉及阻水带,它们的阻水机理是在这些材料中含有一种遇水可膨胀的材料,当水份从电缆端头或是从护套缺陷中进入后,这种材料就会遇水迅速膨胀阻止水份沿电缆纵向进一步扩散,这样就实现了电缆纵向防水的目的。
Waterproof cable diameter water way is generally divided into two watertight and radial. Watertight commonly used are water-blocking yarns, water blocking tape and water blocking powder, which contains a water-blocking mechanism is the water-swellable material in these materials, when the water from the sheath from the cable headend, or after entering the defects, the rapid expansion of this material will prevent water moisture further spread longitudinally along the cable, thus achieving a longitudinally watertight cable purposes.