This three way valve allows either two or three pipeline routes to be connected. The internal cylinder rotates and locks the desired connection. Due to its shape the valve is almost pocket free and is therefore successfully used in the chemical and in the paint industry. The T41 can be operated manually (hand lever) or automatically. In combination with a pig stop insert and a pig sensor the T41 can also be used for launching and receiving of a pig. Thus the pig can be deviated into another pipeline or driven back into its home station.