News 2021年6月1日 139
1、Definition and application
Steel-plastic composite tape for cable is mainly used in the outer sheath of communication cable, and sheath material bonded together to form a comprehensive sheath, to protect the cable core from moisture erosion of the moisture barrier role, while the cable core has an armored role, resistance to external forces, for the laying of communication cables in a variety of applications, such as mechanical protection to ensure the stability and reliability of the application.
2、The main performance of the product
1）Excellent mechanical properties
Due to the good bonding between the composite tape and the plastic sheath, the shield layer and the outer sheath form a whole by making the strength of the metal assembly combined with the extensibility and fatigue resistance of the plastic sheath, which improves the mechanical properties of the cable line.
2) Reliable moisture resistance
The steel-plastic composite tape has a good barrier effect on the intrusion of moisture, thus protecting the cable core.
3）High corrosion resistance
Since the metal tube shielding tape is coated with plastic layer on both sides, it sets up an isolation layer against chemical corrosion between the metal component layer and corrosive water and gas.
Section II Development history
Sheathing material (it should also include armor) is one of the important components of cable-specific materials. In the first half of the twentieth century, lead plus steel wire, steel tape and oiled hemp asphalt were the main materials of sheathing. As pure lead will appear folded crystal phenomenon after extrusion into the sheath, so the lead-clad cable before the 1920s had the common phenomenon that the lead sheath formed micro cracks after the precipitation of the product, which led to the sheath leakage, loss of sealing effect and failure and scrap. This led to a major accident that interrupted the use of communication and power lines. The introduction of lead-antimony alloy in the 1930s and the implementation of its strict process ratios made the life of cable sheathing increase exponentially. There are still some late-1930s lead-clad cables that do not leak and are still in normal operation. Alloy lead-clad cable life has been proven to be more than 70 years, this alloy lead-clad sheath cable is still used as the first choice for submarine power cables, which require long life and high reliability transmission lines.
Following the lead-clad cable, aluminum and plastic were also applied to the sheath, aluminum-plastic, steel-plastic composite bonded sheath materials were introduced into the cable industry in 1949 and 1951, respectively, in the communications fiber optic cable, cable and part of the force cable applications.
Domestic steel-plastic composite tape is in the hewu fiber optic cable project when the war, after many arguments and began to apply the trial system. The emergence and application of domestic aluminum-plastic composite tape a little earlier, but in the 90 years before and after regardless of the composite tape manufacturing length or composite tape quality can not meet the requirements of optical cable production, some strict requirements of the optical cable factory can only be imported from abroad. After several years of market cultivation and manufacturers’ efforts in the early 1990s, the two kinds of domestic composite tape in cable factories and optical cable factories have been commonly used.