The production process of PVC hose mainly includes the following steps:
Raw material preparation: First, according to the product performance requirements, select appropriate PVC resin, plasticizer, stabilizer, lubricant and other raw materials, and determine the ratio of each component. Perform quality inspection on raw materials to ensure that they meet production requirements, and perform necessary pretreatment such as drying and mixing.
Kneading: Put PVC resin, plasticizer, stabilizer, lubricant and other raw materials into the kneading machine in a certain order. The usual order of feeding is PVC resin, plasticizer, stabilizer, lubricant. During the kneading process, the temperature is controlled at 100~110 degrees Celsius, and the kneading time is about 45~50 minutes to ensure that the raw materials are fully mixed.
Granulation: The kneaded material is granulated. During the granulation process, attention should be paid to temperature control to ensure that the material temperature does not exceed the melting point and is lower than the temperature of tube extrusion molding.
Extrusion molding: Add the granulated material to the extruder, and plasticize it through the barrel and screw of the extruder to form a homogeneous molten state. The temperature control of the extruder directly affects the fluidity of the melt and the quality of the extruded product. During the extrusion process, pay close attention to the appearance and viscosity of the molten material to ensure that the surface is bright and there are no unplasticized lumps. Cooling and shaping: The temperature of the hose after extrusion is still very high and needs to be cooled and shaped. For hoses with smaller diameters (less than 60mm), compressed air is usually not required, while hoses with larger diameters need to be blown into the tube to ensure the accuracy and stability of the tube diameter. Cooling water tanks or cooling water tanks with spray devices are also important cooling equipment. Traction and cutting: While cooling and shaping, the traction device is responsible for continuously leading the hose out of the extruder head and cutting it according to the specified length requirements. The traction speed is usually slightly faster than the extrusion speed to improve the transparency and longitudinal fracture resistance of the hose. Curling and packaging: After the traction is completed, the hose is curled and packaged, and finally quality inspection is carried out. The finished PVC hose that passes the quality inspection can be put on the market for sale.
Difference between PVC hose and PVC hard pipe: PVC hose contains a large amount of plasticizers and other additives, which makes its physical properties poor, cannot withstand too much pressure, and has a relatively small range of use. PVC hard pipe does not contain plasticizer components, so it is easier to shape and has stronger pressure resistance.