Title of Invention

A LUBRICATED PLUG VALVE

Abstract

A lubricated plug valve comprising a worm gearbox coupled to a hand wheel for rotating the valve stem; a speed multiplier gearbox for multiplying the number of turns made on the handwheel; a lever and a hydraulic pump, the lever operable by the speed multiplier gear box for activating the hydraulic pump; a reservoir containing sealant connected to the pump for enabling the sealant to be pumped into the valve for lubrication.

Full Text

This invention relates to a lubricated plug valve. The valve incorporates an inbuilt lubrication system with ducts in the body and grooves on plug. The valve sealant is injected inside the valve through a sealant injector fitting provided on the valve. The injected sealant forms a lubrication film between the plug and body when the valve is operated. The lubrication film developed thus provides sealing of the flow media when the valve plug is in closed position. The rotational movement of the Plug inside the body also leads to friction and hence operating torque on the valve stem. The sealant injected in to the system reduces friction and makes the valve operation easier. The valve is usually mounted with the worm gearbox that provides the required mechanical advantage and reduces the operating effort required to turn the valve stem. The common methods of sealant injection existing at present are 1. A manually operated sealant gun 2. A high-pressure sealant gun Both of the above methods involve manual intervention exclusively for sealant charging. This invention relates to automatic sealant charging when the hand wheel of the gearbox is operated for valve operation, thus eliminating separate attention required for sealant charging. The lubricated plug valve according to this invention comprises a worm gear box coupled to a handwheel for rotating the valve stem; speed multiplier gear box for multiply the number of turns made on the hand wheel; a lever and a hydraulic pump; the lever operable by the speed multiplier gear box for activating the hydraulic pump; a reservoir containing sealant connected to the pump for enabling the sealant to be pumped in the valve for lubrication. /.■ Reference will now be made to the accompanying drawings which illustrate (in Fig.l) the known lubricated plug valve and (in Fig.2 & 3 ) by way of example, and not by way of limitation, front and rear views of oiieof various possible embodiments of the lubricated plug valve proposed herein. The known valve (Fig.l) will be seen to comprise the worm gear box G and the handwheel H for manually operating the said gearbox. The gearbox G when operated, turns the valve stem V to turn the plug of the valve. In case of the embodiment of this invention (Fig. 2 & 3) a multiplier gearbox M is coupled to the handwheel H for multiplying the number of rotational turns made on the handwheel. The said gearbox M, when operated by the handwheel H executes a pumping action on the lever L connected to the hydraulic pump P. R is a sealant reservoir housing a piston N. The pump P when operated by the lever L as aforesaid develops the requisite hydraulic pressure which is transmitted to the piston N of the reservoir R. The piston N then forces the sealant in the reservoir into the valve through the injector fitting F. It will be observed that the turning of the valve stem V for operation of the valve automatically results in the sealant from the reservoir to be injected into the valve without any manual intervention. It will be appreciated that other embodiments of the valve proposed herein are possible without departing from the scope and ambit of this invention. We Claim: 1. A lubricated plug valve comprising a worm gearbox coupled to a ^ hand wheel for rotating the valve stem; a speed multiplier gearbox for multiplying the number of turns made on the handwheel; a lever and a hydraulic pump, the lever operable by the speed multiplier gear box for activating the hydraulic pump; a reservoir containing sealant connected to the pump for enabling the sealant to be pumped into the valve for lubrication. 2. A lubricated plug valve as claimed in claim 1 wherein the reservoir has a piston. 3. A lubricated plug valve substantially as herein described and illustrated with reference to the accompanying drawings.

Documents:

0138-che-2006 claims duplicate.pdf

0138-che-2006 description (complete) duplicate.pdf

0138-che-2006 drawings duplicate.pdf

138-che-2006-claims.pdf

138-che-2006-correspondnece-others.pdf

138-che-2006-description(complete).pdf

138-che-2006-drawings.pdf

138-che-2006-form 1.pdf

138-che-2006-form 26.pdf