Assignee
KEYSTONE INT
US96 patents
Top patents by PatentIndex Score
US5579800ADec 3, 1996
Rotary valve position indicator and method
KEYSTONE INT47 citations96
US5823228AOct 20, 1998
Valve manifold
KEYSTONE INT59 citations95
US5036884AAug 6, 1991
Mounting means for fluid pressure transmitters
KEYSTONE INT67 citations94
US5518028AMay 21, 1996
Adjustable magnet carrier for a valve position indicator
KEYSTONE INT36 citations92
US5244183ASep 14, 1993
Fugitive emission sealing assembly
KEYSTONE INT55 citations92
US5044257ASep 3, 1991
Rotary actuator and method for forming a rotary piston
KEYSTONE INT46 citations92
US4846225AJul 11, 1989
Transmission assembly for use with double block and bleed system
KEYSTONE INT37 citations92
US4846212AJul 11, 1989
Bleed valve assembly for double block and bleed system
KEYSTONE INT51 citations92
US4711427ADec 8, 1987
Apparatus for connecting a valve element to a valve stem
KEYSTONE INT25 citations92
US4570901AFeb 18, 1986
Positioning assembly for use with rotatable valves
KEYSTONE INT32 citations92
US4505290AMar 19, 1985
Valve seat assembly and valve
KEYSTONE INT31 citations92
US4399833AAug 23, 1983
Valve assembly
KEYSTONE INT35 citations92
US4169543AOct 2, 1979
Amplitude responsive detector
KEYSTONE INT50 citations92
US5769113AJun 23, 1998
Dual pilot manifold assembly for a safety relief valve
KEYSTONE INT17 citations91
US5590684AJan 7, 1997
Dual pilot manifold assembly for a safety relief valve
KEYSTONE INT33 citations91
US5313976AMay 24, 1994
Top entry ball valve and method of assembly
KEYSTONE INT49 citations91
USRE34610EMay 17, 1994
Mounting means for fluid pressure transmitters
KEYSTONE INT29 citations91
US5269347ADec 14, 1993
Fluid pressure isolator apparatus
KEYSTONE INT37 citations91
US5054374AOct 8, 1991
Rotary actuator
KEYSTONE INT50 citations91
US5011116AApr 30, 1991
Shock absorbing sealing means for flow control devices
KEYSTONE INT26 citations91
US5007330AApr 16, 1991
Rotary actuator and seal assembly for use therein
KEYSTONE INT45 citations91
US4685611AAug 11, 1987
Butterfly valve construction having a composite seat
KEYSTONE INT32 citations91
US4616803AOct 14, 1986
Declutchable valve override
KEYSTONE INT63 citations91
US4079746AMar 21, 1978
Valve assembly having adapter means
KEYSTONE INT38 citations91
US3982725ASep 28, 1976
Valve actuator
KEYSTONE INT86 citations91
US5172716ADec 22, 1992
Recirculation valve
KEYSTONE INT28 citations90
US4870989AOct 3, 1989
High temperature safety relief system
KEYSTONE INT26 citations90
US4682758AJul 28, 1987
Disk/stem connection apparatus for butterfly valve
KEYSTONE INT30 citations90
US5469805ANov 28, 1995
High visibility valve position indicator
KEYSTONE INT61 citations89
US4541612ASep 17, 1985
Rotatable shaft assembly
KEYSTONE INT29 citations89
US5292155AMar 8, 1994
Method and apparatus for mounting an instrument assembly on a main flow line
KEYSTONE INT47 citations88
US5012841AMay 7, 1991
Pressure reducing and conditioning valves
KEYSTONE INT46 citations88
US5005605AApr 9, 1991
Conditioning valve
KEYSTONE INT31 citations88
US4589281AMay 20, 1986
Material level detector and control
KEYSTONE INT35 citations88
US4226118AOct 7, 1980
Level detector
KEYSTONE INT37 citations88
US5333638AAug 2, 1994
Automatic recirculation valve
KEYSTONE INT20 citations87
US5494071AFeb 27, 1996
Mounting system for pressure transmitters
KEYSTONE INT30 citations86
US4967783ANov 6, 1990
Recirculation valve with pilot valve
KEYSTONE INT29 citations86
US4941502AJul 17, 1990
Low pressure recirculation valve
KEYSTONE INT33 citations86
US4659064AApr 21, 1987
Apparatus for fixing the position of a valve element shaft in a bore
KEYSTONE INT32 citations86
US4457490AJul 3, 1984
High temperature valve and seat therefor
KEYSTONE INT21 citations82
US3985151AOct 12, 1976
Valve actuator
KEYSTONE INT51 citations82
US5064169ANov 12, 1991
Shock absorbing means for flow control devices
KEYSTONE INT20 citations81
US4773625ASep 27, 1988
Corrosion-resistant overlay for the edge of butterfly valves
KEYSTONE INT22 citations81
US4701938AOct 20, 1987
Data system
KEYSTONE INT36 citations81
US4410163AOct 18, 1983
Valve seat
KEYSTONE INT25 citations81
US4189950AFeb 26, 1980
Manual control apparatus
KEYSTONE INT28 citations81
US4023432AMay 17, 1977
Actuator having universal-type joint assembly
KEYSTONE INT24 citations81
US5261437ANov 16, 1993
Method and apparatus for monitoring and analyzing recirculation control system performance
KEYSTONE INT21 citations80
US5249593AOct 5, 1993
Fluid pressure relief system for pressure vessels
KEYSTONE INT15 citations80
Showing the top 50 of 96 patents by PatentIndex Score.