The Control Seal Rising Stem Ball Valves (RSBV) sealing mechanism is based upon axial movement only. The sealing is not liable to friction or tearing. This friction free quarter turn mechanical energised sealing does not generate abrasion on the seal and compared with other types of valves, it results in an exceptionally long lifetime.
The stem of the Control Seal RSBV makes only a small axial movement when opening or closing. The stem is always balanced. No stem rotation occurs in combination with axial movement when opening or closing.
An important aspect of the lifetime of a valve is the sealing mechanism. Almost all valves, like Standard Ball, Gate, Plug and Butterfly valves have their sealing mechanism based upon shear force and friction.