Regulating valve

A regulating valve, which is attachable in particular in a bore, executed with a female thread, of a hydraulic door closer. The regulating valve has a body adjoined by a regulating section and has a thread located at the body. In order to provide a regulating valve which has a simple configuration, and in which an unwanted, independent adjusting of the regulating valve is excluded during operation, at least one prominence is provided in a reception for an insert part. The prominence engages in a surface of an insert part such that, upon an axial rotational movement of the regulating valve, the insert part is moved in rotational direction. The insert part cooperates in a clamping and a sealing manner with the bore or the female thread of the door closer. In one embodiment, the prominences act as a cam for the insert part.