Straight seam steel pipe products are widely used in water supply projects, the petrochemical industry, the chemical industry, the electric power industry, agricultural irrigation, and urban construction. They are among the 20 key products developed in our country. Straight seam steel pipes are used for liquid transportation: water supply and drainage. Straight seam steel pipes are used for gas transportation: coal gas, steam, and liquefied petroleum gas. Straight seam steel pipes are used for structural purposes: piling pipes, bridges; pipes for docks, roads, building structures, etc. The die-casting skills and reagent comparison of straight seam steel pipes are things that users need to understand. The following is a detailed introduction:
1. Straight seam steel pipe casting: a pressure processing method that uses the reciprocating impact of a forging hammer or the pressure of a press to change the blank into the shape and size we require.
2. Kneading: It is a steel processing method in which metal is placed in a sealed kneading cylinder and pressure is applied on one end to squeeze the metal out of regular die holes to obtain products of different shapes and sizes. It is mostly used for the production of non-ferrous metals. Material steel.
3. Straight seam steel pipe rolling: A pressure processing method in which the steel metal blank passes through the gap (various shapes) of a pair of rotating rollers. Due to the compression of the rollers, the material section is reduced and the length is increased.
4. Drawing steel: It is a processing method that draws the already rolled metal blank (shaped, tube, product, etc.) through the die hole into a cross-section to reduce the length and increase the length. Most of them are used for cold processing.
The die-casting technology of straight seam steel pipe metal is no longer a secret. As early as the 1930s, the West had discovered that steel, like other softer non-ferrous metals, could be deformed by the rolling method. This new technology was quickly promoted as soon as it was launched. Because its technology is simple and easy to learn, the production equipment and basic costs are very low, and the straight-seam steel pipes it produces are rich and diverse, reliable, and widely used, the upgrade of the technology has attracted scientific research. The staff pay more attention. About ten years later, a British company successfully developed a glass lubricant, which made the straight-seam steel pipe rolling technology spread rapidly in various countries. Before this, the traditional steel pipe rolling production technology used graphite as a lubricant. However, graphite lubricant has its fatal shortcomings:
1. The heat transfer efficiency is high, the heat insulation is poor, and the mold heats up quickly and wears out quickly, making it difficult to roll long products.
2. The carbon content of the product is high, and intergranular corrosion is prone to occur when stainless steel is produced. Therefore, the carburized layer must be removed after completion to increase the cost.
3. Increased ecological pollution damage.
Compared with graphite lubricant, the advantages of glass lubricant for straight seam steel pipe are:
1. The heat transfer efficiency of glass is low, the insulation work on the surface of the workpiece is done well, and the service life of the mold is guaranteed.
2. The lubrication ability is three times higher than that of graphite, and the production speed and width are correspondingly increased, thereby expanding the range of products produced by the rolling machine.
3. Glass lubricant has stable chemical properties and will not cause design defects.
4. The concentration of glass can be adjusted at will to obtain different physical properties (such as softening point, viscosity, etc.) to adapt to the needs of rolling products with 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 the production of straight seam steel pipes.
Three ways to ensure smoothness as required when producing straight seam steel pipes are:
1. Rolling mold: The general method for smoothing the rolling mold is to press the glass powder into a glass mat. Before rolling the straight seam steel pipe, clamp the glass mat between the steel and the rolling mold. To keep the glass mat in the center The softening effect under the action of the collision is exerted to a good extent, and the shape of the manufactured glass mat matches the shape of the roll mold inlet cone and steel end.
2. Rolling drum and mandrel: The glass agent used for lubrication of the rolling drum and mandrel is powdery, with small particles and a high softening degree, and is then applied to the inner hole and outer surface of the steel. In addition, you can also wrap glass cloth around the steel surface and wrap glass cloth strips around the mandrel.
3. Removal of the glass film on the surface of the steel pipe: Due to the use of glass lubricant during rolling, a thin layer of glass film will remain on the inner and outer surfaces of the rolled steel pipe. This film is just like ordinary glass, hard and It is brittle, and will have an impact on the product after it is put into use, so it must be removed. Removal methods include mechanical and chemical methods. Mechanical methods that can be used include shot peening, water cooling, and stretch straightening. If chemical methods are used to remove the glass film, we all know that the chemical properties of glass are quite stable, so if chemical methods are used, strong acidic or alkaline liquids should be used. However, the disadvantage of the pickling method is that it is highly corrosive to various steel pipe raw materials, which may cause pickling on the surface of the steel pipe. It is especially highly corrosive to carbon steel, so it is not cost-effective or appropriate to use pickling alone. Therefore, most of them now use the combined acid-base removal method.
Post time: Jan-16-2024