DeZURIK standard BHP High Performance Butterfly Valves are available with standard steam jackets for less rigorous requirements, but BTG Tail Gas Valves include unique features which keep the valve at process temperature and protect critical bearing and seat areas. In addition to steam jacketing the body, internal steam passage ports are located near the upper and lower body bearings. These features prevent hydrogen sulfide and other media from solidifying, freezing the bearings, damaging the seat and preventing tight shutoff.