Top and bottom gate valve for removing and replacing renewable seating elements

Claim 1

A valve having improved means of removing and replacing the seat element without the necessity of disconnecting the valve from piping or other apparatus, comprising: a valve body having a flow passageway therethrough, and upwardly extending bonnet attachment portion having a bonnet opening communicating with the fluid passageway, and an opening in the lower portion of the body opposite the bonnet attachment portion, the lower opening likewise communicating with the flow passageway, the valve body including means of attachment to other flow conducting apparatus, the body having paralleled seat retaining guides to each side of said flow passageway; a seating element removably supported in the valve body having a flow passageway opening therein coaxial with the body flow passageway opening, the seating element having an annular seating surface surrounding the flow passageway, the seating element having extending lip portions on the opposite sides thereof slidably received in said body seat retaining guides; a gate member vertically positionable in the valve body between a closed position in which said seating element seating surface is contacted, closing the valve against fluid flow therethrough, and open position in which said gate member is withdrawn upwardly within said bonnet opening permitting free passage of fluid through the valve; means extending partially externally of the valve body of vertically positioning said gate member between opened and closed positions; means removably retaining said seat in said seat retaining guides; and an upper removable cover plate sealably closing said upper opening and a lower cover plate removably covering said lower opening in said valve body, and permitting, when the said cover plate is removed from either one of said upper and lower openings, the removal and insertion of said seating element through the said one of said openings.