Large-diameter plastic-coated steel pipes are mainly made of spiral steel pipes or seamless steel pipes as the base material. It is not recommended to use straight-seam welded pipes. Straight-seam welded pipes are usually not as good as spiral steel pipes in terms of pressure bearing, and the cost i

Straight seam steel pipes are steel pipes with welds parallel to the longitudinal direction of the steel pipe. They are usually divided into metric electric welded steel pipes, electric welded thin-walled pipes, transformer cooling oil pipes, etc. The production process of straight seam welded pipes

First, the selection of submerged arc steel pipe: 1. For pipelines with high peak-shaving requirements, due to the uneven gas consumption of users and frequent fluctuations in pipeline pressure, the steel pipe is subjected to great alternating stress. Existing defects in the pipe will expand under

The main processing methods for large-diameter steel pipes are: 1. Forging steel: a pressure processing method that uses the reciprocating impact force of the forging hammer or the pressure of the press to change the blank into the shape and size we need. 2. Extrusion: It is a processing method in

The surface quenching and tempering heat treatment of straight seam welded steel pipe is usually carried out by induction heating or flame heating. The main technical parameters are surface hardness, local hardness, and effective hardened layer depth. Hardness detection can be carried out by Vickers

Do you know how spiral steel pipes are sawed off? Are there any issues that need attention? Here is a brief introduction for everyone. After a series of processes such as forming, welding, and cooling, spiral steel pipes still need to be sawed. In this link, the length of the technical spare rule

Thick-walled straight seam steel pipes are made by rolling long strips of steel strips of certain specifications into round tubes through high-frequency welding units and welding them into straight seams. The shape of the steel pipe can be round, square, or special-shaped, depending on the sizing ro

Slag inclusion in welded steel pipes is slag remaining inside the weld. From a theoretical analysis, the main reasons for slag inclusion in submerged arc automatic welding welds are the following three points: ① There are many inclusions in the raw materials (including parent materials, welding wire

First, thick-walled steel pipes require daily maintenance during use: Thick-walled steel pipes are widely used steel varieties. It directly affects economic benefits and personnel lives. Countries around the world attach great importance to the inspection of thick-walled steel pipes and use various

First, the introduction of the high-frequency welding process of submerged arc steel pipe: 1. Control of weld gap: After multiple rollers roll, the strip steel is fed into the welded pipe unit. The strip steel is gradually rolled up to form a round tube blank with a tooth gap. The pressing amount o

1. Ultrasonic detection: When ultrasonic waves are propagated in the material being tested, the acoustic characteristics of the material and the changes in the internal structure have a certain impact on the propagation of ultrasonic waves. By detecting the degree and situation of the influence of u

First, straight seam steel pipe production temperature: In the process of producing straight seam steel pipes, the temperature must be strictly controlled to ensure the reliability of welding. If the temperature is too low, the welding position may not reach the temperature required for welding. Wh

Spiral welded steel pipe and straight seam welded steel pipe have different technical characteristics and production processes, and have many differences and distinctions in production. They have different functions and uses, and the value they show in use is also different. The comparison of techni

First, the leakage location and condition. The bolts connecting the flanges on both sides of the DN150 valve body are leaking. Due to the extremely small gap between the flange connections, it is impossible to eliminate the leakage by injecting sealant through the gap. The leakage medium is steam, t

A galvanized steel pipe is generally called a cold-dip steel pipe. It adopts an electroplating process. Only the outer wall of the steel pipe is galvanized, and the inner wall of the steel pipe is not galvanized. Hot-dip galvanized steel pipe adopts the hot-dip galvanizing process, and both the inne

1. Quality defects and prevention of tube billets: The tube billets used in the production of seamless steel pipes can be either continuous casting round tube billets, rolled (forged) round tube billets, centrifugally cast round hollow tube billets, or steel ingots can be used directly. In the actua

Seamless carbon steel pipes are a commonly used steel product that is widely used in many industries. Understanding the density of seamless carbon steel pipes is essential for the correct selection and use of steel pipes. First, what is the density of seamless carbon steel pipes? Density is the

In the steel industry, seamless steel pipe is a common and widely used steel product. 1. What is a 48-inch seamless steel pipe? 48-inch seamless steel pipe is a seamless steel pipe specification with a specific outer diameter and wall thickness. In this specification, "48 inches" means that the