US1884442A - Valve - Google Patents

Description

Patented Oct. 25, 1932 UNITED STATES PATENT orrrc RICHARD WELLS AND FRANK M. SMALL, 0F BARTLESVILLE, OKLAIIOIYIA, ASSIGNORS 'TO WELLS VALVE & EQUIPMENT CORP., OF BARTLESVILLE, OKLAHOMA VALVE Application filed February 7, 1931. Serial No. 514,615.

This invention relates to improvements in valves, and more particularly to improvements in valves of the type used to control pressure fluids such as steam.

It is well known that steam passing through such valves, rapidly wears and pits the valve seat so that it is necessary to cut off the flow through the line while the seat is replaced. Obviously, this results in disadvantages and the primary object of the present invention is to eliminate the necessity of replacing the valve seat. I have found in actual practice that a seat constructed in accordance with my invention has the seating surface protected. Consequently, the seat will last indefinitely and will always provide a perfect seal.

Another object of the invention is to provide a valve seat having a seating surface protected, both by a vertical wall and a horizontal flange, whereby steam or the like in passing the seat will be caused, by said wall and flange, to travel over the seating surface in such a way that it will not affect such surface.

A further object is to provide a globe valve including a novel cooperation valve seat and valve head, the latter being shaped to assist the protecting parts of the seat in preventing the steam or the like from directly striking the seating surface.

\Vith the foregoing objects outlined and with other objects in view which will appear as the description proceeds, the invention consists in the novel features hereinafter described in detail, illustrated in the accompanying drawing, and more particularly pointed out in the appended claims.

In the drawing,

Fig. 1 is a vertical sectional view partly in elevation of a known type of globe valve provided with my improvements, and showing the valve in closed position.

Fig. 2 is a similar view with the valve in open position, and indicating by arrows how the pressure fluid flows through the valve without affecting the seating surface.

Fig. 3 is a top plan view of the improved valve seat.

Fig. 4 is a side elevation of the same.

Referring to the drawing, 5 indicates a valve casting having a detachable bonnet 6 to which the valve stem is threaded, as shown at. 7. The stem has a conventional hand wheel 8 at its upper end, and at its lower end it is swiveled at 9 to my improved valve head 10. This head has a piston portion 11 of cylindrical form, and extending outwardly from the upper end of the head is'an annular flange 12 of L-shaped cross section. This flangeand the piston form an annular groove 13 in the under side of the head, andthe outer wall of this groove merges into an annular flared surface 14- that is arranged at lower edge of the flange and cooperates with the seating surface of the valve seat l5which will nowbe described.

The seat, as best shown in Figs. 3 and 4', is of ring shape, and provided with a. medial outwardly extending annular flange 16, below which the wall of the seat is threaded as at 17 for detachable connection to a partition 18 of the casing which forms the port through which the pressure fluid travels when the valve is open.

The seat has at its upper end a cylindrical wall 19, and between the wall and the flange 16, the outer surface of the seat is flared or of frusto-conical shape, as at 20 to cooperate with the flared surface 14 of the valve head. As the wall 19 projects outwardly from said surface, any steam or otherpressure-fluid in passing by the valve seat, will be directed over and out of impinging contact with the surface 20. In other words, the only steam which will contact with the surface, will be that formed by eddy currents, and there will be no direct impingement of steam on the seating surface 20, as that surface will be out of the path of movement of the pressure fluid. In Fig. 1, it may be seen that when the valve is closed, the piston 11 is within the ring forming the valve seat, and the vertical wall 19 is within the groove 13. It will therefore be understood that no steam can pass through the valve until the surface 14 is moved away from the surface 20. In other words, in cutting off the flow, the flow will be stopped before the surface 14 and 20 contact, and this will prevent any wire-drawing.

ibb

When the valve head is raised from the seat by manipulation of the hand wheel, the steam travels in the direction of the arrows shown in Fig. 2 and is deflected over the surface 20. This hiding of the seating 20 behind the wall 19 and flange 16, I have proven by actual tests, protect he seat from becoming pitted and badly scored by steam when the valve is used for throttling purposes. On one valve which was used for test purposes, a groove was cut completely around the outside of the surface 20 in the flange 16, but the seating face itself was unharmed. This construction has been so satisfactory that it has been possible to construct the seat and valve head of cast'iron, bronze or other soft metals, and have them outlast seats in other valves made of the toughest steels.

The flange 12 has the same effect on the flow through the valve as a sharp projection into a stream of water. It deflects the stream away from the seating face and forms an eddy which provides a blanket over the seating face, thus preventing cutting.

While I have disclosed what I now consider to be a preferred embodimentof the invention in such manner that the same may be readily understood by those skilled in the art, I am aware that changes may be made in the details disclosed, without departing from the spirit of the invention, as expressed in the claims.

What we claim and desire to secure by Letters Patent is: w 1. In a valve, an annular valve seat having an external flared surface from which projects an annular wall, and a valve head cooperating with said seat having a piston portion movable into the seat and an overhang- 0,- ing flange with a flared surface which snugly engages the flared surface of the seat, said piston having a flat bottom which when the valve is opened, tends to direct fluid flowing through the seat, outwardly over said wall; 1} 2, In a valve, a detachable annular valve seat having an external flared surface from which projects an annular wall, and a valve head cooperating with said seat and having a piston portion movable into the seat, and an overhanging flange with a flared surface which snugly engages the flared surface of the seat, said seat also having an annular projecting flange positioned at the widest portion of the flared surface of the seatand'arranlged substantially at right angles to said wa 3. A globe valve including an annular valve seat provided at one end with an outwardly extending substantially cylindrical Wall, the external surface of the seat having a frusto-conical face, the narowest portion of said face merging into the external surface of said wall and a valve head cooperating with said seat and comprising a piston por- IQ tion that is movable into the seat, said valve head also having an overhanging flange forming with the piston portion an annular groove to receive said cylindrical wall of the valve seat, the edge of the flange having a frusto-conical surface which snugly engages the frusto-conical surface of the seat when the valve is closed, said piston having a flat bottom which when the valve is opened, tends to direct fluid following through the scat, outwardly over said wall.

4. A globe valve including a detachable annular valve seat provided at one end with an outwardly extending substantially cylindrical wall, the external surface of the seat having a frusto-conical face, the narrowest portion of said face merging into the external surface of said wall, and a valve head coopcrating with said seat and comprising a piston portion that is movable into the seat, said valve head also having an overhanging flange forming with the piston portion an annular groove to receive said cylindrical wall of the valve seat, the edge of the flange having a frusto-conical surface which snugly engages the frusto-conical surface of the seat when the valve is closed, the seat being provided at the widest portion of its frusto-conical surface with an outwardly extending flange.

In testimony whereof, we hereto afiix our signatures.

RICHARD VELLS. FRANK M. SMALL.

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