Fake steel pipes are prone to folding. Folding is a variety of fold lines formed on the surface of the steel pipe, and this defect often runs through the entire longitudinal direction of the product. The reason for the folding is that the inferior manufacturers pursue high efficiency, the amount of pressure is too large, and ears are produced. Folding occurs during the next rolling. The folded product will crack after bending, and the strength of the steel pipe will drop greatly.
Fake steel pipes often have pitting on the surface. The pitting is caused by the irregular uneven surface of the steel pipe caused by severe wear of the rolling groove. Because inferior steel pipe manufacturers want to pursue profits, the rolling groove rolling * exceeds the standard.
Fake steel pipes are prone to scarring. There are two reasons: 1. The material of the inferior steel pipe is uneven and there are many impurities. 2. The guide equipment of the inferior material manufacturer is simple and easy to stick to the steel. These impurities bite the rollers and easily cause scarring.
The surface of fake and inferior materials is prone to cracks because its blank is adobe, which has many pores. During the cooling process, the adobe is subjected to thermal stress, resulting in cracks, and cracks after rolling.
Fake and inferior steel pipes have no metallic luster and are light red or similar to the color of pig iron. There are two reasons for this: 1. It’s blank is Adobe. 2. The rolling temperature of fake and inferior materials is not standard. Their steel temperature is visually measured, so it is impossible to roll according to the specified austenite area, and the performance of the steel pipe naturally cannot meet the standard.
The transverse ribs of fake and inferior steel pipes are thin and low, and they often appear to be underfilled. The reason is that to achieve a large negative tolerance, the manufacturer’s first few passes of the finished product are too large, the iron mold is too small, and the hole mold is not filled.
Post time: Dec-20-2024