In the construction and design of electrical engineering, the wiring method of cable protection steel pipes is a crucial link. Among them, the way of cable protection steel pipes entering and exiting from the bottom of the bridge has aroused widespread discussion and attention. Whether it complies with relevant specifications and standards has a far-reaching impact on the quality, safety and subsequent maintenance of the project. Next, let us explore this technical issue in depth.
Relevant specifications and standards
Before we explore the compliance of cable protection steel pipes entering and exiting from the bottom of the bridge in depth, we first need to conduct a comprehensive and detailed review of a series of important specifications and standards followed by the domestic electrical industry.
At present, the main reference specifications in my country’s electrical field, such as “GB 50303-2015 Construction Quality Acceptance Code for Building Electrical Engineering” and “GB 50217-2018 Power Engineering Cable Design Standard” and other authoritative documents, have made detailed and clear provisions for each link of cable laying.
Take GB 50303-2015 Construction Quality Acceptance Code for Building Electrical Engineering as an example. It strictly limits the path selection, fixing method, protection requirements and spacing from other facilities of cable laying.
According to relevant statistics, there are dozens of clauses involving cable laying in the specification, covering the whole process from design to construction and acceptance.
In GB 50217-2018 Design Standard for Power Engineering Cable, it is emphasized that the selection and laying method of cables should be based on comprehensive consideration of multiple factors such as power load, environmental conditions and fire protection requirements. According to incomplete statistics, in this standard, the proportion of clauses directly or indirectly related to cable laying methods exceeds 20%.
However, it should be pointed out that although these specifications clearly explain the general principles and common methods of cable laying, the description of the relatively special situation of cable protection steel pipe entering and exiting from the bottom of the bridge is often not direct and specific. This requires us to combine rich professional knowledge and practical experience in actual operation to make comprehensive, in-depth and accurate comprehensive judgments.
Technical advantages and risks
Technical advantages
In specific engineering scenarios, the cable protection steel pipe entering and exiting from the bottom of the bridge does show some significant technical advantages.
First, from the perspective of power transmission efficiency, this wiring method can effectively reduce the bending degree of the cable. According to experimental data, for every 10% reduction in the bending degree of the cable, the loss during power transmission can be reduced by about 5%.
By entering and exiting the cable from the bottom of the bridge, the direction of the cable can be optimized, unnecessary bending can be reduced, and the efficiency of power transmission can be significantly improved.
Second, in terms of space utilization, this method shows high flexibility. Especially in those environments with complex bridge layouts and extremely limited space, such as renovation projects of some old buildings or compact industrial plants, the bottom entry and exit method can better adapt to site conditions and achieve efficient use of space.
According to relevant case analysis, the space utilization rate of projects using the bottom entry and exit method is about 15% higher than that of traditional wiring methods on average.
Potential risks
However, we cannot ignore the potential risks of this wiring method.
From the perspective of physical protection, the cable entry and exit from the bottom increases the possibility of external physical damage. For example, in areas where people and equipment are active, cables may be more susceptible to squeezing, collisions, and accidental trampling by heavy objects. According to industry accident statistics, electrical failures caused by physical damage to cables account for about 10%.
Furthermore, waterproofing and moisture-proofing are another key issue. If there are omissions in construction and protective measures, the risk of cables getting damp will increase significantly, which will in turn affect their insulation performance.
Studies have shown that if the insulation performance of cables decreases by 10%, the probability of short circuits and leakage in the system will increase by more than 20%, seriously threatening the safety and reliability of the entire electrical system.
In addition, from the perspective of construction, the bottom entry and exit undoubtedly brings higher complexity to the installation of the bridge. This not only puts more stringent requirements on the technical level of construction personnel, but also increases the difficulty of construction and the challenge of precision control.
According to the construction cost analysis report, the construction cost of the bottom entry and exit method is about 15% higher than the conventional method on average, and the construction period is also extended by about 10% accordingly.
Analysis of practical application cases
In order to more intuitively and deeply understand the actual effect and possible problems of the cable protection steel pipe entering and exiting from the bottom of the bridge, let us analyze it in detail through some specific practical application cases.
In the construction of the electrical system of a large commercial complex, due to the particularity of the building structure and the limitation of the spatial layout, some areas had to adopt the method of cable protection steel pipe entering and exiting from the bottom of the bridge.
During the construction process, the construction team strictly followed the relevant specifications and standards, carefully designed the construction plan, and strengthened a series of protective measures, such as adding special protective sleeves to the cables, reasonably setting waterproof bends, and using high-quality sealing materials to ensure waterproof and moisture-proof effects.
After long-term operation monitoring and data statistical analysis, the electrical system in this area has shown stable and reliable performance, without obvious faults and safety hazards.
According to operation and maintenance records, in the past three years, the electrical fault repair rate in this area has been lower than 10% of the average level of the entire commercial complex, which fully proves that under certain conditions, the carefully designed and constructed bottom entry and exit method can achieve good operation results.
However, in another industrial plant project, the cable protection steel pipe was also used to enter and exit the line from the bottom of the bridge, but due to the problems of lax quality control and inadequate protective measures during the construction process, a series of adverse consequences were caused.
The cables showed obvious signs of moisture during operation, and even short circuits occurred in some areas, which had a serious impact on production activities. According to the production loss assessment report, the production line downtime caused by this electrical failure exceeded 50 hours in total, and the direct economic losses reached millions of yuan.
These contrasting cases clearly show that the compliance and effectiveness of the cable protection steel pipe entering and exiting the line from the bottom of the bridge does not only depend on the choice of the wiring method itself, but is closely related to multiple key links such as quality control during construction, the degree of perfection of protective measures, and later operation and maintenance management.
Conclusion and Suggestions
Based on the above comprehensive and in-depth analysis, we can draw an objective and practically guiding conclusion: the wiring method of the cable protection steel pipe entering and exiting the line from the bottom of the bridge itself is not necessarily illegal, but to ensure its compliance and safety, a series of strict conditions and requirements must be met.
First, in the design stage, scientific and reasonable planning should be carried out based on an in-depth understanding of relevant specifications and standards, combined with the specific characteristics and needs of the project.
Fully consider many factors such as the actual spatial layout of the site, the type and number of cables, the expected power load, environmental conditions (such as humidity, temperature, the presence or absence of corrosive substances, etc.) and protection requirements, and formulate a detailed and accurate wiring plan.
According to incomplete statistics, electrical system failures caused by unreasonable design account for about 15%, which fully highlights the importance of scientific design.
Secondly, during the construction process, the construction quality must be strictly controlled to ensure that every link meets the specifications and design requirements. Select high-quality materials, such as high-quality cable protection steel pipes, reliable protective sleeves and sealing materials.
At the same time, construction personnel should have skilled skills and rich experience, and be able to accurately carry out construction operations according to the design plan. For key nodes and hidden projects in the construction process, strict quality inspection and acceptance should be carried out to ensure that the construction quality is impeccable.
Finally, during the project acceptance stage, the acceptance personnel should conduct comprehensive, detailed and strict inspections based on relevant specifications and standards.
Focus on checking whether the wiring method meets the design requirements, whether the protective measures are in place, whether the cable fixing and connection are firm and reliable, and whether the waterproof, moisture-proof, and fire-proof properties meet the expected goals. Only through a strict acceptance procedure can we ensure that the wiring method truly meets the overall requirements of safety, reliability, and ease of maintenance.
In short, the compliance issues of the cable protection steel pipe entering and exiting the line from the bottom of the bridge require us to judge and deal with them with a rigorous attitude and scientific methods. Only in this way can we ensure the quality and safety of electrical engineering projects and provide reliable power support for the development and progress of society.
Post time: Sep-11-2024
