a device for connecting components made of fusible plastic , especially pipes of a fuel pipeline or a fuel line to a fuel tank of a vehicle . the device includes a heating element having ends which are used to supply electrical energy . the device is easy to use , simple to mount , and produces a functionally reliable welded joint between the components . to achieve this , one component includes a retaining body for a retaining tool , and the two ends of the heating element extend onto the retaining body where they can engage contact elements on the retaining tool .