The ordinary dredging hose adopts one-time vulcanization, and the vulcanization temperature is about 150℃. The floating dredging hose contains PE foam material, which will degrade and shrink when the temperature is above 110℃. Therefore, the floating dredging hose is vulcanized at different temperatures before and after winding the foam material.
Mechanical pressure process of flange rubber lining part
Rubber is a viscoelastic body, and the dredging hose is composed of multiple layers of rubber material. During the molding process, it needs to be pressurized several times to ensure that the layers are firmly bonded. However, in the process of lining the flange connection parts, manual pressure is often used for a long time, which often cannot guarantee the compactness of the pipe wall. If this part is lined with steel rings and ceramics, the pressure will not be enough. A new mechanical pressure device, which can pressurize the rubber-lined part of the flange, has received very good results.
Flange sealing type
In the past, flange sealing type is entire flange surface for a sealing surface or on the basis of this, in the lower edge of the screw hole and then add a “O” seal.In recent years, however, step seal or semi-seal is adopted. Step seal means the flange surface sealant in two layers, the first layer covers the entire flange surface, thickness 3mm, the second layer covers the lower edge of the screw hole from 10mm to the inner circumference of the hose, thickness 3mm, semi-seal that the rubber layer only covers the screw hole within the part.
CNC molding
For many years, dredging hose basically adopts the manual forming method, which often makes the quality of hose manufacturing subject to subjective factors. In recent years, the CNC molding process is gradually booming up.