Exhaust gas after-treatment device for diesel engine of heavy commercial vehicle, has adjusting screw for adjusting spring force, where screw is screwed into internal thread made of thermoplastic and is material-fitly connected with thread

摘要

The device has a pump for setting a urea-water-solution under pressure and for conveying the pressurized solution to a dosing valve for an exhaust stream. A pressure limiting valve (41) limits pressure of the solution. A closure body (51) tightly lies against a valve seat (50) under a spring force, where the spring force is adjustable by an adjusting screw (53) made of thermoplastic. The adjusting screw is screwed into an internal thread (54) made of thermoplastic and is connected with the internal thread in a material-fit manner.