With sealing rings or gaskets, hydraulic pipe fittings are corresponding seals, which are sold. Raw material tape is not recommended. Failure to seal will lead to oil leakage. Raw material belt will be polluted by inhalation oil, especially easy to cause valve jamming or plugging control oil outlet. If raw material tape must be used, care should be taken not to bring raw material out of the joint when winding, so as not to be sucked into the tank by oil.