Silicone Hose Manufacturing Process

We use HCR silicone rubber, additives and pigments, and place them in a running open mixing mill to mix them thoroughly. Adjust the hardness and ensure the mixing time is correct.

We press the compounded silicone rubber material into sheets of the required thickness, then select a suitable reinforcement fabric (polyester, aramid, fibreglass) and calender it into sheet rolls.

Using aluminium or stainless steel moulds, our skilled technicians wind silicone sheet and silicone-reinforced layer around the mould in specified layers. Then remove trapped air, compact each layer and control wall thickness, whilst winding the high-temp-resistant tape to the specified tightness.

We place the moulded silicone hoses into the vulcanisation oven, set the temperature to 180 °C and the time to 25 minutes, and heat them to carry out vulcanisation. The exact vulcanisation time must also be determined based on the hose thickness and construction. Controlling vulcanisation time is a crucial step in ensuring silicone hose quality.

Once the silicone hoses have been vulcanised and cooled, the clear tape on the hose surface is removed. Lubricant is then injected onto the inner wall of the hose to ensure thorough lubrication, after which the inner wall is flushed with high-pressure water to dislodge the mandrel. Straight couplers are easier to demould than those with greater bends, such as 90°or 45°elbows.

After silicone hoses have been removed from mould, make them dry. Then, using a nylon mold to trim off the extra material from both hose end to the required length specified in the drawings. This step is crucial; the lengths at both ends must be cut precisely, as being too long or too short will affect the installation and use of the silicone hose.

For custom-made silicone hoses, it is usually necessary to print the customer’s logo, part number, batch number, sizes, etc. We generally use screen printing or heat transfer printing, and the print colour is usually white. After printing, the material must be heat-treated to enhance colour fastness and prevent colour fading.

The final step is to inspect every hose, checking for surface defects, bubbles, cracks, exposed reinforcement, dimensions (internal diameter, external diameter, wall thickness, length, and bend angle), as well as various tests, such as burst pressure, vacuum, tensile strength, and resistance to heat, oil, and fuel.