• Details

The large-caliber bend pipe is bent by a complete set of bending equipment, which can be divided into two processes: cold simmering and hot pushing. No matter which kind of machine equipment and pipeline, most of them use large-caliber elbow pipe, which is mainly used for oil transportation, gas transportation, liquid transportation, engineering bridge construction, etc.

Method of use

Analysis on the main reasons causing the quality decline of large-caliber bend pipe and methods for attention:

1. When the pipe is completely bent, the tensile stress on the lateral arm wall of the middle layer is reduced under the action of external force distance M, while the tensile stress on the lateral arm wall of the middle layer is decreased under the action of &1, and the compressive stress on the inside is reduced. The joint forces N1 and N2 change the cross section of the pipe. Based on this factors, cause a decline in the quality of large diameter bend the main reason for the RX and SX so GBJ235-82, RX value of under various pressure levels and thinning of the lateral mass were made specific provision, the purpose is to control the value of RX and SX, to ensure the quality.

2. has spoken of the preceding article, large diameter pipe material when the lateral tensile, compression of the inside of the neutral axis location is different with the methods of large diameter bend, when he worked in top bending type (compression bending) neutral axis in about 1/3 from the outer wall, the rotating bending (bend), neutral axis in two-thirds from the outer wall. Therefore, it is beneficial to use the method of rotary bending for thin-wall pipe bending.

3. The precision of the bending tire is also one of the factors influencing the quality of the large-caliber bending tube. In the manufacture of bending tire, we require the user to select the corresponding bending tire according to the bending pipe diameter while the specification and size are controlled within a certain tolerance range.

4. The bending performance and surface corrosion of the pipe itself may also affect the quality of large-caliber pipe bending. In the field construction, the operator also needs to know the material of the pipeline being processed, the processing performance and the production judgment of the surface corrosion.

5. R is provided now. (bending radius/outside diameter) curve diagram for users to select the relationship between pipe diameter and wall thickness. It reflects the influence of relative bending radius and relative wall thickness on the quality of large-caliber bending pipes. According to the acceptance specifications of pipeline processing, cold-formed steel pipes are: medium/low pressure is 4D; high pressure is 5D. We bend tire design for R = 4 d (special another case may be), so I plant the production of large diameter pipe bender is mainly choose the relative wall thickness SX, the upper part of the figure is no core shaft area, central figure for the common core shaft, the lower part of the figure as a special core shaft section. Because of the special core shaft design and manufacture are very difficult, the operation is not very convenient, so general factory does not supply. Special circumstances may be agreed upon separately.

6. Influence of lubrication on product quality during molding:

Enterprises in the traditional production technology of large diameter bend, to get a better surface quality of large diameter bend, will take a lot of ways, including: adopting more advanced large diameter pipe bending machine, with higher mold intensity, or use the way such as lubricant. Used in large diameter pipe bender and high strength of the mold, companies often need to be a very big money to complete, only use of large diameter bend lubrication products is relatively cheap and quick to enterprise product quality requirements. But in the traditional production process, oil-based lubricant can satisfy the business enterprise of large diameter bend in the production of large diameter bend the requirements of the quality of large diameter bend, but oil-based lubricant of large diameter bend is not easy to clean and pollution to the environment is very prominent, so that enterprises must adopt more means to eliminate because of big diameter pipe using oil-based lubricant products impact on the quality of the final product, putting in more effort and money. And IRMCO water-based of large diameter bend the arrival of the grease that is to satisfy the enterprise product quality requirements of large diameter bend, and can avoid and reduce the enterprise because the oil-based lubricant products and increase the investment of large diameter bend, optimize enterprise production process completely.

In the process of traditional oil-based lubricant products application, the enterprise the production efficiency is greatly restricted, because oil-based lubricant products and very difficult to cleaning liquid, more caused the pollution of production environment and working conditions for workers, enterprises to clear these pollution often need to spend a lot of money and manpower. The adoption can reduce or even avoid the above human and material costs of cleaning pollution for the enterprise, its features of no-washing and direct welding can greatly improve the production efficiency and product quality of the enterprise. However, the use of IRMCO water-based large-caliber elbow grease can usually reduce the consumption of oil by 50-80% compared with traditional lubricating oil, which can save enterprises more costs.