Introduction To High-Precision Metal Tube Bending Processing

Introduction to High-Precision metal tube Bending Processing

High-Precision tube bending parts are widely utilized in various fields such as home appliances, medical equipment, electrical systems, scientific instruments, aerospace, intelligent manufacturing, and food machinery. The demand for precise metal tube is continuously expanding, with bent tubes being a crucial component. The dimensional accuracy of the metal tube components, the fullness of the bending arcs, the cleanliness of the products, and the quality of the appearance are all key factors in measuring product quality. These aspects are also integrated into an overall solution involving processes such as CNC machining, welding, pressure testing, ultrasonic cleaning, and surface treatment. Metechworks has a mature overall solution for tube bending manufacturing and has been engaged in tube bending processing for 15 years.

When designing and producing metal tube bending products, the following factors must be considered:

1. Materials Suitable for tube Bending

The metal materials used for bent pipes include: steel tubes, stainless steel tubes, copper alloy tubes, aluminum alloy tubes, and titanium alloy tubes. For piping components that require corrosion resistance, options include stainless steel tubes, aluminum alloy tubes, copper-nickel alloy tubes, and titanium alloy tubes. The most commonly used material is stainless steel. There are many types of stainless steel tubes; for instance, the nickel content in SUS304 and SUS316 differs, leading to variations in cost. SUS316 has a higher nickel content, which provides better corrosion resistance, making it typically used in food machinery, chemical processes, experimental equipment, or products with high corrosion resistance requirements. SUS304, on the other hand, has a broader range of applications.

Stainless steel tubes can be categorized into welded stainless steel tubes and seamless stainless steel tubes. Welded stainless steel tubes are formed from stainless steel strips which are then welded together, generally used for ordinary decorative pipes or standard components. However, for high-pressure fluid piping, seamless tubes are required to ensure product reliability. The quality and performance requirements for bent tube components include: dimensional accuracy and aesthetic quality. Fluid tubes or heat exchange tubes must meet quality requirements such as pressure resistance, high and low-temperature resistance, and good thermal conductivity.

2. Wall Thickness of tubes and Bend Radius

When designing tubes components, it is important to consider the thickness of the different metal tubes and the parameters of the bend radius. Typically, the bend radius should be greater than the diameter of the pipe. For example, if the pipe has a diameter of 12.7mm, the designed bend radius should exceed 12.7mm to avoid the occurrence of flattened bends. If the cross-sectional area of the bent section decreases, it may affect the internal fluid flow during operation. A well-rounded bend enhances the aesthetic appeal of the product.

Beyond the bend radius, the physical state of the metal pipe can also directly affect the bending outcome. For instance, if the material is too soft, it may lead to wrinkling on the inside of the bend. Conversely, if the material is too hard, it may cause cracking on the outer side of the bend, primarily due to the greater deformation of the outer material compared to the inner material. When designing bent pipe components, limited installation space or higher aesthetic requirements necessitate not only smaller bend radii and fuller, more attractive bends but also the achievement of high precision in dimensions. Therefore, it is essential for the bending factory to have extensive experience in bending as well as excellent equipment and molds.

3. Tube Bending Equipment and Tube bending die

Bending equipment includes manual bending machines, hydraulic bending machines, and CNC bending machines. Typically, high-precision bending is achieved using CNC bending. Hydraulic bending machines may experience variations in operational pressure due to changes in hydraulic oil temperature during use, leading to instability in product dimensions. Different diameters and wall thicknesses of metal pipes require the selection of various models of bending equipment. High-precision bending usually requires equipment with slightly higher power, which is beneficial for ensuring stable bending quality.

Tube Bending die are a key factor in ensuring the quality of the bends. Bending die consist of components such as wheel molds, clamping molds, pushing molds, core rods, and anti-wrinkle molds. The material of the molds and the differences in processing precision can vary significantly; high-quality molds can improve the quality of the bending process. Additionally, the installation and debugging of molds are crucial, relying heavily on the professional experience of engineers. For small radius bends, the position of the core rod and the compatibility between the wheel mold and clamping mold directly affect the quality of the bend, and even the speed of bending can impact quality.

A bending factory with rich experience, when producing high-precision, small-radius, and complex bent tube products, first creates a Design for Manufacturing report.

They fully understand the various quality requirements of clients for the products, scientifically justify the production processes, clarify the control methods for key quality control points of the bent pipe products, determine optimal material parameters, and design high-quality tooling molds and quality inspection tools based on different products. This approach minimizes material costs and helps avoid issues such as quality defects or product flaws.