The structure of OPGW cable the application structure of OPGW cable has experienced the development process from the end of 1970s to 2000. Dozens of OPGW cable structures have been developed and produced in the world. The cable core structure is as follows:
1) Aluminum pipe structure; 2) center beam aluminum pipe structure; 3) aluminum framework structure; 4) spiral aluminum pipe structure; 5) single layer stainless steel pipe structure (middle) core stainless steel pipe structure, stainless steel pipe laying structure; 6) composite stainless steel pipe structure (center stainless steel pipe structure, stainless steel pipe laying structure).
There are two kinds of stranded wires, AA wire (aluminum alloy wire) and as wire (aluminum clad steel wire), outside the core wire of OPGW. At present, more and more stainless steel pipe OPGW cable fittings are used in the world. The stainless steel pipe optical fiber unit structure is divided into single-layer stainless steel pipe optical fiber unit and composite stainless steel pipe optical fiber unit. The main features of composite stainless steel tube optical fiber unit are as follows:
(1) The optical fiber on-line redundancy control can obtain and guarantee very accurate and regular redundancy;
(2) The inner lining of stainless steel pipe can effectively improve the mechanical strength of stainless steel;
(3) The production of optical fiber unit does not need the cold drawing process of steel pipe to avoid the internal stress defects caused by cold drawing;
(4) The composite stainless steel tube can protect the optical fiber from welding arc and scald, and the inner plastic tube is smooth to protect the optical fiber from the wear of the sharp edge of the weld.
The main characteristics of stainless steel pipe OPGW cable are as follows:
(1) The product structure is consistent with the traditional ground wire structure;
(2) Make full use of the physical and electrical characteristics of the conductor;
(3) Within the applicable range of the steel tube specification for optical fiber, the increase or decrease of the number of optical fiber cores does not affect the outer diameter of the optical cable;
(4) The optical cable has compact structure, large mechanical strength and small outer diameter;
(5) The construction method of optical cable is similar to that of traditional ground wire.
The products of OPGW optical cable fittings have the following characteristics:
1. It has the advantages of good consistency of optical fiber surplus length, high welding quality of steel pipe and high filling rate of optical fiber paste in steel pipe.
2. Fiber loss coefficient is small. According to the optical path test, the average loss of most optical fiber lines (including joints) in l550rim window is less than 0.2ldb/km.
3. Technical services to satisfy users. In the engineering design stage, Tongguang carefully understands the line engineering situation, communicates with the design institute comrades, discusses with each other and reaches a consensus. In the construction phase, Tongguang will send engineers with rich practical experience to carry out on-site supervision and optical fiber integration.