Silicone hoses are generally produced using the "continuous extrusion + hot air vulcanization" process. The entire production line works like stretching noodles, extruding the rubber material into a tubular shape and then curing it as it moves forward. Finally, it is cut and rolled up. Here is the detailed process.
1. Raw material selection
Raw rubber: Generally, methyl vinyl silicone rubber (MVQ) with a Shore A hardness of 50-80 is selected.
Colorants/Pigments: Food-grade, non-toxic mineral pigments. Medical-grade multi-purpose platinum sulfide system.
2. Ingredients and Mixing
Use a 25L mixer or an open mill to blend the raw rubber, fillers, color mother, and vulcanizing agent together.
Mix well and let it stand for 8-12 hours to eliminate stress. Then cut it into strips or particles for storage.
3.Extrusion molding
Single or double screw extruders, barrel temperature 45 - 80 ℃, die head 80 - 120 ℃.
4.One sulfurization (using a hot air tunnel)
The tunnel is 6 to 12 meters long, with a temperature of 200 to 300 degrees Celsius, and lasts for 30 to 120 seconds.
5.Secondary vulcanization (deep oven vulcanization)
At 200 ℃ for 2 to 4 hours, completely decompose and volatilize the residual peroxides/low-molecular-weight substances, thereby enhancing heat resistance and reducing compression permanent deformation.
6.Online cooling and diameter measurement
The device is cooled to room temperature through spraying or air cooling; the laser diameter measuring instrument provides real-time feedback, and any deviation will trigger an automatic alarm.
7.Demolding, cutting
8.Inspection and Packaging
Appearance: Free of bubbles, impurities, and yellowing.
Dimensions: Inner diameter, wall thickness, ellipticity
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