A new type of insulation protection reinforcement

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A new type of insulation protection reinforcement for cross crossing of distribution lines


cross crossing of power lines is common in distribution lines, and the potential safety hazards are particularly serious. Although the CPU operating frequency (11.0592Mhz) of the original power supply may be abnormal, the Department has fully considered the influence of various possible factors in the design and construction process, strictly implemented the regulations and specifications, and maintained a sufficient crossing safety distance, but due to changes in the external environment of line operation or illegal intrusion of other line facilities, the distance between lines or lines to ground potential is too close, The high-voltage electrical discharge enters the low-voltage or other weak current lines, causing equipment and even personal injury accidents

at present, power supply enterprises often adopt the following methods to solve the problem of insufficient safety distance for power line crossing: ① line raising or reconstruction. This is a thorough solution to the problem, but it is difficult to invest in large-scale and power outage construction; ② Negotiate with the infringing department to transform or dismantle the infringing object by means of consultation, mediation and requesting government administrative intervention. However, due to the handling of such problems, there are too many external interference factors, and the result is often time-consuming but fruitless; ③ Temporary measures are taken to reinforce the crossing sections of the line with some insulating materials, such as thermoplastic materials and tree crossing strips. As a result, the urgent need can be temporarily solved. However, due to the lack of rules to follow, the use of materials is disordered and nonstandard, and its insulation level is difficult to be guaranteed. In addition, there are generally no effective waterproof measures at the interface, which is very likely to lead to serious corrosion of the internal conductor by rain, dew and other erosion, The circuit is heated and damaged after a long time. In view of this, the power supply department urgently needs to develop a kind of special bare line insulation reinforcement material to deal with such problems that cannot be transformed at present, so as to prevent them from happening

According to the research, we found that the common line crossing problems in the power system at present mainly focus on the 10kV to low-voltage, weak current lines and some grounding bodies. Therefore, the main direction of our research and development is to solve these problems first

as this special-purpose insulation protection reinforcing material, in order to make it advanced and applicable, it must have the following characteristics: ① it can maintain good insulation performance in harsh natural environment; ② With eye-catching identification, strong anti-aging ability, and firm joint surface, sealing and sealing; ③ Convenient and fast construction; ④ It is convenient for mass production, large-scale use, and the ratio of credit to price is appropriate

after a large number of formula adjustments, tests and tests, we found that the polymer blend modified material, i.e. high elastic rubber insulator blend material, is feasible in processing technology. The profile has high elasticity and strong plasticity, which is not only convenient for production and construction, but also can maintain good insulation performance and anti-aging ability in the strict aging test environment. Therefore, we decided to use it as the main material

2 technical realization scheme

through the hard work of the R & D personnel in the past two years, through numerous design modifications, sample trial production and tests, the preliminary finalized crystal production has passed the "entrusted inspection" of the national wire and cable quality supervision center, and obtained the "patent authorization" of the national patent office and the appraisal of scientific and technological achievements organized by the Department of science and technology of Jiangsu Province

2.1 product structure

see Figure 1

Figure 1 product structure diagram

2.2 product structure description

the product is made of multi-layer insulation reinforcing materials with different properties. It is divided into three layers, including an inner insulation layer, a shaping filling layer and a high-strength insulation protective layer, which are successively wrapped around the periphery of the power cable. There is an insulation umbrella at both ends of the entire reinforcement: the inner insulation layer is deformation measurement overview: polymer insulation material, The shaping and filling layer is a hot-melt insulating material, and the high-strength insulating protective layer is a sheet made of anti-aging and heat shrinkable material, which is wrapped in the outermost layer of the reinforcement, and its two butt edges are connected through a long strip link buckle: the product features mainly include:

1) the insulating protective reinforcement adopts heat shrinkable material as the main insulating material, which can maintain good insulation performance in harsh natural environment, Strong anti-aging ability

2) the specially designed combined umbrella skirt effectively prevents the erosion of bare wires by rain and dew

3) both the umbrella skirt and the chain buckle are made of self luminous materials with eye-catching marks, and the joint surface is sealed and firm

4) convenient and fast construction

5) it is convenient for mass production, large-scale use, and the ratio of credit to price is appropriate

3 technical parameters and performance of products

3.1 insulation performance

see Table 1 for the monitoring report of the national wire and cable quality supervision and inspection center that meets the insulation performance requirements. Table 1

3.2 crossing performance index

with reference to the requirements of line crossing distance in the code for electric power design, this product can be used to partially reinforce the lines whose crossing distance is not enough to meet the requirements of the specification. In a popular sense, it means local cabling. However, we do not recommend using this product to change the national electric power design specification when new lines are installed. The recommended service life of this product is 3 years. Products with special specifications and requirements can be customized

3.3 the application conditions and specifications

the applicable angle and product selection table are shown in Table 2, table 2

4 conclusion the successful development of insulation protection reinforcement for power line crossing provides a convenient safety protection method for power supply enterprises with insufficient safety distance for power distribution line crossing, and largely solves the problem of insufficient safety distance for power supply enterprises for many years, However, it should be noted that as a temporary reinforcement measure, it must not be used as a basis for the construction, production, operation and other departments to reduce the requirements of regulations and specifications. To thoroughly solve the problem, it needs to be included in the rectification plan for gradual transformation. In addition, as a temporary insulation reinforcement, it can not be compared with the cable or cable head. It has distance requirements and age requirements. Therefore, power supply enterprises should use it strictly according to the regulations. If there are special needs, it should be customized separately. (end)

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