Plastic stop valve and method for the production thereof

Method for the production of a stop valve for pipes, with a housing (1) which consists of plastic, has two pipe connectors (2) and in which a blocking element (3), which can be adjusted by an actuation unit between a flow position and a blocking position, is mounted at least by means of bearing rings (4) and sealing rings (5), wherein plastic is injected around an inner part, which comprises the blocking element (3), the bearing and sealing rings (4, 5), a bearing collar (8) and an insert (6), in the pre-assembled state with the use of an adhesion means to form the housing, said housing having an inner shape, said method comprising the steps of:

• a) making a molding, which corresponds essentially to the outer shape of the insert (6) and to the inner shape of the housing (1) in the region of the insert (6), from a plastic by means of injection molding;
• b) injecting a plastic, which constitutes the insert (6), onto and into the molding made in the method step a) while simultaneously forming a fusion-welded connection between the plastic of the molding and the material of the insert (6);
• c) assembling the stop-valve inner part which consists of the blocking element (3), the bearing rings (4), the sealing rings (5), the bearing collar (8) and the insert (6) (together with the molding), and placing the inner part in an injection mold;
• d) injecting plastic free of clearance volume around the inner part pre-assembled in the method step c) while simultaneously forming a fusion-welded connection between the plastic of the molding and the material of the housing (1).