Hawa Engineers Ltd. Manufactures Teflon Line Type Plug Valve. Hawa Engineers Ltd. Is an ISO 9001 registered company. Teflon Line Type Plug Valve is designed of valve comprising of a body with a tapered, or less frequently, a parallel plug. Teflon Line Type Plug Valve can be automated by means of quarter-turn actuators. It is designed by various variants like non-lubricated, fluoropolymer sleeved, lubricated and pressure balanced for on/off isolation of fluids and have inherent quick opening flow characteristics similar to bail valves, although specially designed eccerstric plug designs may be used for flow control applications.