Analysis of the main reasons for the decline in the quality of steel bending pipe and precautions

1. During pure bending, the outer arm wall of the neutral layer of the pipe is thinned by the tensile stress &1 under the action of the external force distance M, and the inner side is thickened by the compressive stress. The combined forces N1 and N2 change the cross-section of the pipe. Based on this factor, the main reason for the decline in the quality of steel bending pipe is RX and SX. Therefore, GBJ235 stipulates the RX value and the thinning amount of the outer side under various pressure levels to control the values of RX and SX to ensure quality.

2. As mentioned in the previous article, when a steel bending pipe is used, the material is tensile on the outside and compressed on the inside. The location of the neutral axis is different from the steel bending pipe method. When working in the top bending (compression bending) mode, the neutral axis is about 1/3 away from the outer wall, and when working in the rotation bending (return bending) mode, the neutral axis is 2/3 away from the outer wall. Therefore, it is beneficial to use the rotation bending method for thin-walled pipe bending.

3. The accuracy of the bending tire is also one of the factors affecting the quality of steel bending pipe. When we manufacture bending pipes, in addition to controlling the size requirements within a certain tolerance range, we also require users to select the corresponding bending pipe according to the diameter of the bent pipe when using it.

4. The bendability and surface corrosion of the pipe itself may also affect the quality of steel bending pipe. During on-site construction, the operator also needs to understand the material, processing performance, and surface corrosion of the processed pipe to make a production judgment.

5. Now we provide an R. (bending radius/pipe outer diameter) relationship curve for users to refer to when selecting the relationship between pipe diameter and wall thickness. Reflecting the influence of relative bending radius and relative wall thickness on the quality of steel bending pipe, according to the acceptance specifications for pipeline processing: cold-bent steel pipes are 4D for medium and low pressure and 5D for high pressure. Therefore, our bending tire design is R=4D (special circumstances are determined separately), so for the steel bending pipe machine produced by our factory, the main choice is the relative wall thickness SX.

6. The impact of lubrication on product quality during the molding process: In the traditional steel bending pipe production process, enterprises will take many measures to obtain better steel bending pipe surface quality, including using more advanced and high-end steel bending pipe machines, using higher-strength molds, or using lubricating products. To use high-end steel bending pipe machines and high-strength molds, enterprises often need to invest a lot of money to complete them. Only the use of steel bending pipe lubricating products is relatively cheap and fast to meet the requirements of enterprise product quality.

However, in the traditional production process: oil-based bending pipe lubricating products can meet the quality requirements of steel bending pipes in steel bending pipe production, but the difficulty of cleaning and environmental pollution of oil-based bending pipe lubricating products are very prominent. In this way, enterprises must adopt more means to eliminate the impact of oil-based bending pipe lubricating products on the quality of the final product, and invest more energy and funds for this.

The arrival of IRMCO bending pipe water-based grease not only meets the company's requirements for steel bending pipe product quality, but also avoids and reduces the company's increased investment due to the use of oil-based bending pipe lubricating products, and completely optimizes the company's production process. In the application process of traditional oil-based lubricating products, the company's production efficiency is greatly restricted, because the fluidity and extremely difficult cleaning of oil-based lubricating products have caused pollution to the production environment and workers' working conditions. It often takes a lot of money manpower and material resources for companies to remove these pollutions.

The use of IRMCO water-based bending pipe grease can reduce or even avoid the human and material resources required for the above-mentioned pollution cleaning. Its characteristics of no-cleaning and direct welding can greatly improve the company's production efficiency and product quality. The amount of IRMCO water-based bending pipe grease can usually be reduced by 50%-80% compared with traditional lubricants, which can save more costs for companies.