First, the hydroforming concept:

The hydroforming(hydroforming(internal high pressure forming)) was called hydroforming,it's the metal material forming process that uses liquid (oil or water) as a rotating medium to control the internal pressure and material flow to achieve the purpose of forming hollow parts. hydroforming(hydroforming(internal high pressure forming)) equipment usually processes stainless steel, aluminum, copper, iron and other materials by converting the mechanical energy of the hydraulic machine into the kinetic energy of the liquid.

the basic principle behind hydroforming:

Second, the principle: The principle of hydroforming(hydroforming(internal high pressure forming)) is to use Pascal's law to press the tube blank into the mold cavity by internal pressurization and axial force feed to form the desired workpiece. For parts with a curved axis, the tube blank needs to be pre-bent to approximate the shape of the part and then pressure formed.

Third, the overall design plan:

Automotive parts utilization The advanced hydroforming(hydroforming(internal high pressure forming)) process design mainly includes the following aspects:

the Applications in the automotive industry about auto-hydroforming

1) Adopt digital 3D design and simulation technology to realize the overall structural design of the automobile parts, make the product series diverse and individualized, and select the appropriate mold materials according to the mold designed in the high pressure molding;

2) The accuracy and strength of the internal high-pressure forming die are the key factors to ensure the strength and dimensional accuracy of the automotive components. It is necessary to use theoretical calculations and experimental methods according to the characteristics of the components to ensure the strength of the die can eliminate the internal force of the original pipe during the high-pressure forming process. The effect of elastic deformation and internal stress deformation of the shaped product ensures the shape consistency of the product;

3) Study the relationship between the pressurization mode of high-pressure oil and the variable cross-section shape of the component in the high-forming forming process, determine the relationship between pressurization time and pressure, adjust the pressurization speed, establish reasonable process parameters, and develop suitable hydraulic control equipment. . The above research mainly realizes the integrated design of the new automobile parts and the integral forming of the internal high pressure by precisely controlling the expansion of the special-shaped parts under the action of the high-pressure liquid.

Fourth, the application of hydroforming(internal high pressure forming) technology in automobiles:

With the continuous improvement of domestic and foreign technology, hydroforming(internal high pressure forming) has been widely used in the manufacture of many parts in the automotive industry. Its advantages are mainly reflected in the one-piece integral molding of extremely complicated shape pipe parts, and the traditional method. Compared with the same parts, the most notable feature of the parts used for hydroforming(internal high pressure forming) is that the product quality is lighter, the service life is longer, and the cost of use of the material is higher. The following is a brief description of several automotive parts that are molded in high pressure

Hydroforming processed products,for example:

Five, car exhaust system

The traditional manufacturing process of automobile exhaust pipe is to cast or stamp two half shells and then form welding or use the pipe material as blank for CNC bending, pipe expansion, shrinkage processing and then group welding. The molding technology using the above method has many parts and components, and the welding process often results in slow production efficiency, high cost, and poor overall rigidity of the welded parts. The use of advanced hydroforming(internal high pressure forming) technology to integrally form the automobile exhaust pipe, reducing the manufacturing process of many parts and components, and the reliability of the product quality is higher, directly eliminating or greatly reducing the weld formed by welding, so that the inner surface of the product It is smoother and smoother, and the beneficial effect is that the resistance of the exhaust gas is small. Therefore, the application of this technology realizes the weight reduction and cost reduction of the product under the premise of ensuring the quality of the exhaust pipe.

Sixth, car frame parts:

In the field of manufacture of automotive frame components, the hydroforming(internal high pressure forming) technology also ensures a reduction in the demand for materials, thereby reducing costs. For example, the front axle assembly is manufactured by conventional methods. When 6-8 sheet metal parts are welded together and formed by internal high pressure, the number of individual parts can be greatly reduced to only about 2 or 3, which makes the mold cost even more. Low, reducing production costs, without the need for multiple positioning and welding operations.

Seven, the car side bar:

The car side bar is a type of car exterior parts. It is usually installed on the lower side of the left and right doors of the SUV vehicle. It is used for the driver and passengers to step on and off when taking the car, and to take into account the left and right collision avoidance of the vehicle. The traditional body side bar body is formed by bending a stainless steel or carbon steel material, and then a plastic non-slip rubber block is assembled at a position corresponding to the upper and lower sides of the side bar.

Eight, the car luggage rack:

The car luggage rack is a bracket that is mounted on the roof to facilitate the strapping of large items, and is the basic component of the vehicle roof. The car luggage rack has both beautiful and practical functions, which can make the car carry larger luggage items, facilitate travel, and make the shape of the vehicle more beautiful, and has been widely used. The traditional luggage rack bracket manufacturing process is formed by extrusion and bending of aluminum tubes, and the assembly can be realized by subsequent assembly and processing of plastic end caps. Therefore, the process is complicated and requires a lot of man-hours, and the metal and plastic composite combination needs to be specifically The disassembly method can be recycled and the material utilization rate is low. The internal high-pressure forming technology can realize the one-piece forming of the whole aluminum alloy or stainless steel luggage rack bracket, which can improve the strength and specification precision of the luggage rack, and can make the shape and specifications of the luggage rack product diversified, and the two ends connected with the vehicle body are not Need to be equipped with plastic joints, saving materials, reducing processes and improving the life of the luggage rack.

Therefore, the application of hydroforming(internal high pressure forming) in the automotive industry plays a positive role in promoting the lightweighting process of automobiles, improving the rigidity and strength of parts, and improving the stability and safety of vehicle applications.