Views: 0 Author: Site Editor Publish Time: 2021-02-26 Origin: Site
The main technological characteristics of spiral steel pipe:
a. During the forming process, the steel plate deforms evenly, the remaining stress is small, and the skin phase is not scratched. The processed spiral steel pipe has greater flexibility in the size and specification of the diameter and wall thickness, especially in the production of high-grade steel-grade thick-walled pipes, especially the small and medium-diameter thick-walled pipes have disadvantages that cannot be compared with other processes. To meet users' more requirements in terms of spiral steel pipe specifications.
b. Using the advanced double-sided submerged arc welding process, the welding can be completed in a good position, and there are no shortcomings such as wrong edges, deviations and incomplete penetration, and the welding quality is simply controlled.
c. The quality inspection of steel pipes is stopped, so that the entire process of steel pipe production is under ineffective testing and monitoring, which effectively guarantees the product quality.
d. The local facilities of the entire production line have the performance of networking with computer data collection systems, and the data is transmitted immediately after the completion of the data, and the local control room will control the technical parameters in the production process.
The spiral steel pipe adopts double-sided submerged arc spiral welding technique to continuously weld the narrow strip (plate) coil to the steel pipe. It is widely used in my country's West-East Gas Pipeline Projects and other long-distance oil and gas pipeline projects, and it is an unnecessary pipe type selected for my country's oil and gas long-distance pipeline projects. Spiral steel pipes are widely used in engineering fields such as artificial gas, kerosene, chemical industry, electric power, thermal power, water supply and drainage, steam heating, penstocks for hydropower stations, thermal power generation, water sources and other long-distance transportation pipelines and piling, dredging, bridges, steel structures and other engineering fields. The thermal stability of spiral steel pipes generally refers to the power that the task is resisting cracks under the alternating effects of cold and heat.
The cracks that occur due to the alternating cold and heat are called thermal stress cracks. The unnecessary reason for the scrapping of die casting molds and hot forging dies in the mold is due to poor thermal stress and stability, which is prone to thermal stress cracks. Regarding die steel, its thermal stability is not necessarily determined by the resistance and strength of the steel. Therefore, the mold steel with good thermal stability and stability must have good resistance and high strength (high wet strength).
The spiral steel pipe skin is impacted by high velocity and turbulent fluid, and is damaged by wear and corrosion together, which is called wear corrosion. Impact corrosion is an unnecessary condition of wear and corrosion. The spiral steel pipe is under the impact of high-speed fluid. If the fluid contains solid particles, the wear and corrosion of the spiral steel pipe will be more serious.
Its appearance features are: local grooves, corrugations, round holes and ravine shapes, which usually flash directional. Exposed equipment in the stopping fluid, such as pipes, three-way, valves, blowers, Lishensi, impellers, heat exchangers, exhaust ducts, etc., can be impacted and corroded. Soft metals such as copper and lead are getting worse.
Spiral steel pipe packaging refers to the outer layer protection that stops for the convenience of transportation or for the protection of the anti-corrosion protection of the spiral steel pipe.
Generally speaking, the packaging of spiral steel pipes is for imported spiral steel pipes, because if imported spiral steel pipes are shipped by sea, the packaging must be stopped for loading and unloading.
The packaging of spiral steel pipes can be divided into the following ways:
1. Bundled packaging is also a bundled type, such as 219 spiral steel pipes, 7 pieces per bundle, and 273 spiral steel pipes 7 pieces per bundle. Both ends of each bundle are equipped with hoisting belts for easy hoisting.
2. Box-type packaging is the use of angle steel, square pipe, channel steel welded into a frame type, the bottom is closed, large and small containers, and the loading and unloading time is followed by the entire box. Thick-walled spiral steel pipe refers to the spiral steel pipe whose thickness is greater than or equal to 14mm. The production of thick-wall spiral steel pipe must use a customized spiral steel pipe production unit. Generally, the production of spiral steel pipe unit is very difficult and simple for the unit. Spare parts are destroyed. The price of the thickness spiral steel pipe unit is generally 1.3-1.6 times higher than that of the ordinary spiral steel pipe unit. However, the production range of thick-wall spiral steel pipe is wide. It can not produce the products of the general spiral steel pipe unit, but can also produce thick-walled pipes.
The production process of the thick-walled spiral steel pipe is: original material---feeding---milling---for the edge---double-sided active welding--no elegance outside visual inspection---welding spot view--- -Non-destructive testing---identification. The proportion of spiral steel pipes in steel pipes has been stable at around 42% to 45% in recent years, and welded pipes have a tendency to rise. Compared with welded steel pipes, spiral steel pipes have strong material reliability and strong type compliance, especially for thick-walled and alloy steels.