US 4,338,961 A · Valve for handling hot caustic alumina solution with provision for grinding

Abstract

A valve structure is provided which can be opened and closed under operating conditions without any adjustment in conditions existing in the system in which the valve is an element. The valve element can be turned with respect to the seat to provide for proper relation between the valve element and the valve seat to grind one with respect to the other during the operating cycle. The valve also includes a clutch having a radial acting trip overload that prevents the valve seat from being damaged during grinding which is effected by turning the valve through the clutch while moving the valve toward the seat during the closing cycle and produces a controlled grinding operation independent of pressure within the valve. When the valve is operated in the opposite direction, the clutch disengages and the actuator mechanism encounters only the thrust forces during the opening cycle. This allows the valve to be easily opened without overloading the system.

Claims11

Dependent claims

A valve comprising,

a valve body having a valve seat,
a closure member formed to fit said seat and control the flow through said valve body,
stem means for moving said closure member toward and away from said valve seat to cause frictional engagement of said closure member on said seat,
rotating means operatively connected to said valve stem means for rotating said closure member relative to said seat to effect a grinding thereof, and
trip means being mounted on rotor means positioned on the lower end of said valve stem means capable of interrupting the rotational movement of said closure member at a preselected frictional force between said closure member and said seat, said trip means including members slidably mounted in slots in said rotor means with one end of said slidable members engaging spring means located in recesses in said rotor means and the other end of said slidable members engaging cam means on a fixed member mounted within said closure member for radial movement, whereby said trip means operates independently of pressure within the body of said valve.

2 more elements

A self-grinding valve comprising,

a valve body having an inlet and an outlet and a valve seat therebetween,
a movable closure member formed to move toward and away from said seat to form a seal therewith and control the flow through said valve body,
valve stem means journaled in said valve body and having a thrust-type coupling with said closure member wherein longitudinal movement of said stem means causes the closure member to move relative to said seat,
rotating coupling means disengagably carried between said stem means and said closure member wherein rotation of said stem means causes selected rotation of said closure member relative to said seat and effect selected grinding of said closure member on said seat, and
trip means interposed in rotor means between the lower end of said stem means and the interior of said closure member to interrupt said rotational movement at a pre-determined frictional grinding engagement between said closure member and said seat, said trip means including members slidably mounted in slots in said rotor means with one end of said slidable members engaging spring means located in recesses in said rotor means and the other end of said slidable members engaging cam means on a fixed member mounted within said closure member for radial movement, whereby said trip means operates independently of pressure within the body of said valve.

2 more elements

Dependencies are inferred from the claim text.

Valve for handling hot caustic alumina solution with provision for grinding

Life of this patent

Valve for handling hot caustic alumina solution with provision for grinding

Life of this patent

Abstract

Claims11