The water swelling process has lower processing costs and higher production efficiency. Mainly speaking, the water swelling process is to use the pressure inside the mold to make the material close to the shape of the mold cavity. For the equipment, the pressure must be stable and the quality is reliable. As a professional manufacturer of water bottles, Auland has to Do better.
What is the water swelling process?
The water swelling process is to use a water swelling machine filled with water to pressurize the material to adhere to the mold cavity shape.
And the water swelling machine is an advanced manufacturing technology for the manufacture of hollow integral components of internal high-pressure forming, the principle is to take the pipe as a blank, take water as the transmission medium, and fill the water with ultra-high pressure into the inside of the pipe, so that it produces pressure on the inner wall of the pipe, seal both ends of the pipe with a punch, use axial feed to provide feeding for pipe forming so that the outer wall of the pipe is completely close to the mold cavity, so as to obtain the desired shape parts. There are many applications of internal high-pressure molding technology in pipe forming, such as stainless steel pipe tee, copper pipe tee, stainless steel card pressure pipe, automotive special-shaped pipe fittings (such as bellows), bathroom faucets, insulated cups, hot water kettles, and other common pipe parts and supplies.
The step of the water swelling process:
- Put the pipe into the mold cavity, and then close the mold, and the end of the pipe is sealed with a punch.
- The water is filled into the inside of the pipe by the sealing punch, and the pressure is applied to the liquid inside the pipe, and the pipe is deformed under the action of internal pressure and axial feeding so that the outer wall of the pipe gradually adheres to the mold cavity.
- Maintain the pressure, wait for most of the outer wall of the pipe to stick to the mold cavity, and then use a larger internal pressure, so that the pipe rounded corners and other parts that are not easy to form are gradually close to the mold cavity to get the desired shape of the formed parts.
The advantages of the water swelling process:
- Less forming process: in the process of high-pressure forming in the pipe, in addition to sealing the pipe, the punch also applies an axial force to the pipe to replenish the pipe forming, improve the forming ability of the pipe, and can also achieve a single forming for multi-section parts. In addition, because the internal high-pressure forming parts have good integrity, so the internal high-pressure forming technology can reduce the amount of welding, and some internal high-pressure forming parts do not need to be assembled and welded.
- Reduce the weight of the workpiece, and improve the utilization rate of materials: most of the internal high-pressure formed parts only need a set of molds, and stamping welding often requires three or more processes, the number of molds required is relatively large, tooling development and subsequent manufacturing costs will be greatly improved. As fewer processes are reduced, so will process waste. In the case of meeting the requirements of parts, the inner high-pressure formed parts can achieve a weight reduction of 20% to 30% compared with the stamped welded assembly, and the material utilization rate can be increased by 30% to 50%.
- Good forming quality: the use of internal high-pressure forming parts, due to the integrity is better, so its strength and stiffness are also higher. In addition, the number of welded parts in the internal high-pressure forming part is small, and the number of welded joints with concentrated stress is also reduced so that the quality of the parts obtained by the internal high-pressure forming is better.
- Less pollution: the internal high-pressure forming technology is an environmentally friendly forming technology, compared to the traditional stamping welding, its noise pollution is small, the working environment is better, in addition, the water required for internal high-pressure forming can be recycled, the environmental impact is small.
What is the stretching process?
The stretching process is a stamping process that uses a mold to form a flat blank into an open hollow part. As one of the main stamping processes, stretching is widely used. The stretching process can be used to make cylindrical, rectangular, stepped, spherical, tapered, parabolic, and other irregularly shaped thin-walled parts, and if combined with another stamping process, more complex shapes can be manufactured.
The use of stamping equipment for product stretching processing, including stretching processing, re-stretching processing, reverse stretching, and thinning stretching processing.
The advantages of the stretching process:
- Save materials.
- From the design and shape, it can produce a special-shaped sink, which is beautiful and generous.
- There is no welding, and the use of solid solution treatment improves the performance of stainless steel. Its disadvantages are: 1, the sink mold input cost is high; 2, the surface treatment is difficult, and it is not easy to make embossing, drawing, and other surfaces.
Stretching process VS water swelling process
- The cost: The stretching process is more expensive than the water swelling process
- The appearance: The stretching process is more precise than the water swelling process. Because the product of the water swelling process has a seam.
- The precision: Because the water swelling process has welding, so the accuracy will be higher, and the stretching process is a one-piece molding, and the accuracy of the product shape will be relatively low.
- Type of production: The water swelling process can make more types than stretching due to welding.
- Please check below comparison pictures.

