Wire and cable accessories refer to some supporting products used in wire and cable construction, so what are the wire and cable accessories? What is the connection method of wire and cable accessories? The following is a detailed introduction to these problems for friends for reference.
Wire and cable accessories
wire and cable accessories are products that connect cables with transmission and distribution lines and related power distribution devices. They generally refer to the intermediate connection and terminal connection of various cables in the cable line. It forms a power transmission network together with the cable. Cable accessories are mainly based on the characteristics of the cable structure, which can not only restore the performance of the cable, but also ensure the extension of the cable length and the connection of the terminal. The reliability of high-voltage cable accessories can be judged from the aspects of electrical performance, sealing and moisture resistance, mechanical performance and process performance.
Connection mode of wire and cable accessories
the connection mode of cable accessories is generally divided into terminal connection and intermediate connection. The terminal connection is divided into indoor terminal and outdoor terminal. Generally, outdoor terminal refers to outdoor cable connector, and indoor terminal refers to the connector of indoor connection cable and electrical equipment. The intermediate connection is divided into straight-through type and insulated type.
Supporting equipment
this set of quality assurance procedures shall at least include the following:
(1) When leaving the factory, the factory test should be strictly carried out on the key parts (for example, rubber stress cone, epoxy resin sleeve of GIS, impregnating agent, preform of intermediate joint, etc.). Carefully check whether the test and measuring equipment is reliable, whether the test method is effective, whether the test personnel are well-trained and whether the test records are complete;
(2) Whether the installation and construction personnel dispatched by the manufacturer are strictly trained and have sufficient construction experience;
(3) Whether the coordination between different departments of the manufacturer is good;
(4) Past sales and operating records.
Types of wire and cable accessories
there are many types of wire and cable accessories, with different types of characteristics and limitations, generally can not replace each other. The common ones are as follows:
(1) Wrapping type: The cable accessories made of rubber strip (self-adhesive) are called wrapping cable accessories, which are easy to loosen, have poor fire resistance and short service life;
(2) Pouring type: thermosetting resin is used as the main material in the field. The selected materials are epoxy resin, polyurethane, acrylic resin, etc. The fatal disadvantage of such accessories is that bubbles are easily generated during curing;
(3) Molded type: mainly used for cable intermediate connection, mold heating on site, and cable integration. The accessory has complex production process and long time, and is not suitable for terminal joints;
(4) Cold shrinkage type: silicone rubber, EPDM rubber and other elastomers are pre-expanded in the factory and formed by adding plastic support strips. During on-site construction, pull out the support strip to make the pipe shrink on the cable under the inherent elastic effect of rubber and make the cable accessory. The accessory is most suitable for construction sites that cannot be heated by open flames, such as mines, petrochemicals, etc;
(5) Heat-shrinkable type: The rubber-plastic alloy is made into different component products with “shape memory effect, and the accessories are made by heating and shrinking on the cable on site. The accessory has the characteristics of light weight, simple and convenient construction, reliable operation and low price;
(6) Prefabricated type: silicone rubber is injected into different components, vulcanized and molded at one time, only the contact interface is retained, and the cable is inserted into the accessories during on-site construction. The construction process reduces the unmeasurable adverse factors in the environment to a minimum, so the accessory has great potential value and is the development direction of cross-linked cable accessories, but the manufacturing technology is difficult and involves a variety of disciplines and industries. The installation materials of prefabricated accessories under the three-pronged mouth and shielding mouth of the cable are still heat-shrinkable materials, so it is actually a combination of prefabricated and heat-shrinkable.
What are The Wire and Cable accessories?
Various intermediate joints and terminal heads of cables are collectively referred to as Cable accessories. The accessories commonly used to make intermediate joints and terminal heads of cables include wiring terminals, connecting pipes, grounding wires, support plates, cable terminal boxes, cable Intermediate Joint boxes, etc.
The most complete knowledge of wire and cable and accessories in the history
what are the advantages of crosslinked Heat Shrinkable cable accessories?
Answer: This is a new type of material. Compared with other types of accessories, it has the advantages of superior electrical performance, small size, small quality, easy installation, and matching materials. It also has weather resistance, anti-pollution, flame retardant and self-extinguishing. Ability.
What are the main properties of electricity?
A; Should have the following main properties:(1) high breakdown strength;(2) low dielectric loss;(3) fairly high insulation resistance;(4) excellent discharge resistance;(5) has a certain degree of flexibility and mechanical strength;(6) long-term stability of insulation performance.
What are the requirements for the mechanical strength of cable conductor connection points?
Answer: The mechanical strength of the connection point is generally lower than the tensile strength of the cable conductor itself. For the fixed power cable, the tensile strength of the connection point is not less than 60% of the tensile strength of the conductor itself.
What requirements should be met for the processing of cable protection pipes?
Answer:(1) The nozzle should be free of burrs and sharp corners, and the nozzle should be horn-shaped. (2) After bending, the cable pipe shall not have cracks and obvious concave collapse, and its bending degree shall not be greater than 10% of the outer diameter of the pipe; The bending radius of the cable pipe shall not be less than the minimum allowable bending radius of the cable penetrated. (3) The metal pipe shall be coated with anticorrosive paint or surface, and the galvanized pipe shall also be coated with anticorrosive paint where the zinc layer is peeled off.
What are the insulating materials used to make cable terminals or intermediate joints?
Answer: There are insulating glue, insulating tape, insulating tube, insulating gloves, insulating resin, etc.
Through the above content, we have learned about the related problems of wire and cable accessories. It can be seen that there are many kinds of wire and cable accessories. When you use them, you must use them according to the requirements of the instructions.