Comparison of die-casting techniques and reagents for straight seam steel pipes

The comparison of die-casting skills and reagents for straight seam steel pipes is something that customers need to understand. The following is a detailed introduction:
1. Straight seam steel pipe casting steel: a pressure processing method that uses the reciprocating impact force of a forging hammer or the pressure of a press to change the billet into the shape and size we need.
2. Kneading: It is a processing method for steel to put metal in a closed kneading box and apply pressure at one end to make the metal extrude from the regular die hole to obtain products with the same shape and size. It is mostly used for the production of non-ferrous metal material steel.
3. Straight seam steel pipe rolling: the steel metal billet passes through the gap (various shapes) of a pair of rotating rolls, and the cross-section of the material is reduced and the length is increased due to the compression of the rolls.
4. Pulling steel: it is a processing method in which the rolled metal blank (type, pipe, product, etc.) is drawn through the die hole to reduce the cross-section and increase the length. Most of them are used for cold work.

The die-casting technology of straight seam steel pipe metal is no longer a secret. As early as the 1930s, the West discovered that steel, like other soft non-ferrous metals, can be deformed by rolling. Once this new technology was launched, it spread quickly, because its technology is easy to learn, production equipment and basic cost are very low, and the types of straight seam steel pipes produced are rich and diverse, reliable, and widely used, so the upgrading of technology has received great attention from scientific research. The attention of the staff. About ten years later, a British company successfully developed a glass lubricant, which made the rolling technology of straight seam steel pipes spread rapidly in various countries. Before this, the traditional steel pipe rolling production technology used graphite as a lubricant. However, graphite lubricants have their fatal disadvantages:
1. The heat transfer efficiency is high, the heat insulation is poor, the mold heats up quickly, the wear is fast, and it is difficult to roll long products.
2. The carbon content of the product is high, and intergranular corrosion is prone to occur when producing stainless steel, so the carburized layer should be removed after completion, which will increase the cost.
3. Increased ecological pollution damage.

Compared with graphite lubricants, glass lubricants for straight seam steel pipes have the following advantages:
1. The heat transfer efficiency of the glass is low, the heat preservation work on the surface of the workpiece is done well, and the service life of the mold is guaranteed.
2. The lubricity is three times higher than that of graphite, and the production speed and width increase accordingly, which can expand the range of products produced by the rolling machine.
3. The chemical properties of the glass lubricant are stable and will not cause design defects.
4. The concentration of the glass can be adjusted at will to obtain different physical properties (such as softening point, viscosity, etc.), to adapt to the product requirements of rolling different raw materials.
5. Clean and environmentally friendly, with no side effects, and little damage to the environment.

To sum up, the glass lubricant product has excellent performance and is the best lubricant for straight seam steel pipe production. The three ways to ensure the smoothness as required when producing straight seam steel pipes are:
1. Rolling mold: the smoothness of the rolling mold is generally to pressing the glass powder into a glass mat. Under the effect of friction, the softening effect is exerted to a good degree, and the shape of the manufactured glass mat matches the shape of the inlet cone of the rolling die and the shape of the end of the steel.
2. Rolling barrel and mandrel: The glass agent used for smoothing the rolling barrel and mandrel is powdery, with small particles and a high softening degree, and then coated on the inner hole and outer surface of the steel. In addition, it is also possible to wrap glass cloth on the surface of the steel and wind glass cloth strips on the mandrel.
3. Removal of the glass film on the surface of the steel pipe: because the glass lubricant is used during rolling, a thin layer of glass film will be preserved on the inside and outside of the rolled steel pipe. This film is the same as ordinary glass, hard and Brittle, it will affect the product after it is put into use, so it should be removed. The removal methods include mechanical and chemical methods. The mechanical methods that can be used include shot peening, water cooling, and stretching and straightening. If the chemical method is used to remove the glass film, we all know that the chemical properties of the glass are quite stable, so if the chemical method is used, there are liquids with strong acid or strong alkali properties. However, the damage of the pickling method is that it is highly corrosive to various steel pipe materials, and may cause pickling on the surface of the steel pipe, especially for carbon steel, so it is neither cost-effective nor appropriate to use pickling alone. Therefore, most of them now use the combined acid-base removal method.