US3026894A

US3026894A - Slurry stop plug

Info

Publication number: US3026894A
Authority: US
Inventors: Charles H Brooks
Original assignee: Sun Oil Co
Current assignee: Sunoco Inc
Priority date: 1958-08-15
Filing date: 1958-08-15
Publication date: 1962-03-27
Anticipated expiration: 1979-03-27

Description

March 27, 1962 c. H. BROQKS SLURRY STOP PLUG 3 Sheets-Sheet 1 Filed Aug. 15, 1958 INVENTOR. CHARLES H. BROOKS 3,026,894 SLURRY STOP PLUG Charles H. Brooks, Swarthmore, Pa., assignor to Sun Oil Company, Philadelphia, Pa., a corporation of New Jersey Filed Aug. 15, 1958, Ser. No. 755,229 4 Claims. (Cl. 137-240) This invention relates to rotatable plug type valves, in general, and more particularly to valves of this type adapted to control the passage of fluid slurries consisting of liquid supported solids.

The control of slurry flows is important in chemical and petroleum industries. Solids supported by liquids are required to be flow-controlled by various manufacturing requirements. These solids may be either soft or hard and in either case, are subject to clogging the flow control apparatus, usually a form of valve.

As is usual in meeting new requirements, known methods and mechanisms are retained to solve the problems as they arise. Standard valves used for controlling the flow of liquids, gases or comminuted solids separately, do not meet the requirements for controlling the flow of liquid supported solids comprising a slurry. The reason for this is the mentioned clogging of the relatively moving parts and resultant stoppage, undue wear and leakage. It is therefore, a primary object of this invention to provide a valve especially adapted to control the flow of slurries.

Another object is to provide a slurry control valve in which a liquid conformable with the slurry composition frees the valve contacting surfaces of solids as a function of normal operation.

Yet another object is to provide a slurry control valve in which the cleaning liquid supply channels in the valve are maintained free of slurry clogging.

And still a further object of this invention is to provide a rotatable plug type valve in which the contacting surfaces are subjected to a washing action of a pressured liquid introduced and channeled through the valve independently of the controlled slurry flow.

Further objects of the invention and the manner in which they are attained will be evident from a reading of the following detailed description, with reference to the attached drawings, in which:

FIGURE 1 is a diagram showing a typical apparatus connection in which the subject valve is used;

FIGURE 2 is an exploded view in perspective showing the valve parts in relative cooperating position;

FIGURES 3, 4, and 6 are sectional views of FIGURE 2, taken on lines 3-3, 44, 55, and 6-6, respectively; and

FIGURES 7 through 10 are additional sectional views repeating FIGURES 4 and 6 for operating description purposes.

As indicated in the initial discussion of the position of this device in the patented art, and the objects for which the particular valve is provided, the problem involves, broadly, cleaning the valve engaging parts of the solid particles of the slurry, as part of the valve operation. Sequential operation, wherein a flushing of standard valve passages with conformable liquids occurs, is known. The advantage of the newly disclosed combination is to perform the washing function continuously and automatically, by reason of the valve structure. Elimination of multi-way washing valves and the resultant operating requirements are thus accomplished.

This and other advantages result from enclosing a valve plug, limited in arcuate movement between an open and closed position, in a valve body especially designed to meet this washing requirement. An area in the valve body, of sufficient dimension to operably bracket the 2 through passage of the valve plug, is circumferentially and longitudinally channeled for the passage of liquid. These channels are covered with sintered porous metal elements shaped to receive the valve plug in close sliding contact. Connecting the channels behind the sintered porous metal elements, plug controlled passages supply the washing liquid from an inlet in the bottom of the valve body.

A clearer understanding of this general description of the device will be obtained from the following detailed reference to the elements of the combination described, in relation to the several figures of the drawing. FIGURE 1 illustrates a typical assembly of elements in which the disclosed valve can be used to great advantage. The valve, generally denoted by the numeral Iii, is operably connected to chamber 12 by conduit 14. An outlet conduit 16 leads from the outlet side of valve 10. Solids to form the slurry in chamber 12 are admitted thereto through conduit 13. Liquid is conducted to chamber 12 as through pipe 29. A feed line 22, in which pump 24 acts as a booster to pressure the conducted liquid, connects to the bottom of valve lil as the source of pressured liquid, for purposes later described. Any liquid which conforms with the chemical requirements of the slurry may be conducted through pipe 22, and need not be a pressured portion of the slurry liquid as shown.

FIGURE 2, an exploded view of valve 10 showing the valve parts in perspective and in cooperating relation, will be the figure of primary reference. For further clarification both in description of elements and operation, reference will be made to FIGURE 1 already described and to the remaining FIGURES Z to 10, inclusive.

The valve comprises three parts, the plug 30, the body 32 and the top or cap 34. It will be evident that the top 34 and the body 32 so closely cooperate that together they form a housing or in more general terminology, a seat means for the plug 30. Continuing in a general vein the description, plug 3%) is shown as a tapered plug, conforming with other valves of this known type. It will be evident, however, that valve plug 30 need not be tapered, but can well be cylindrical in shape and perform the functions outlined.

In detail, valve plug 30 is apertured as at 36, providing a passage therethrough for transmission of the slurry. FIGURE 4 shows this passage aligned with the inlet and outlet of the seat means, later to be described in detail. A transverse channel 38, diametrically disposed across the base of the plug and in operating alignment with passage 36, provides the regulating means for the cleaning action of the liquidthrough the passageways of the valve seat. On the exposed end of the plug 30 as it extends above the top of the housing, a rectangular boss .0 is formed to receive an operating handle. A stop 42 is positioned to fit into an arcuate slot 44 in a ring 46 on the top of the cap 34, limiting the plug to an open and a closed position.

The remaining part of the valve to be described can be called interchangeably a body, a housing, or plug seat means. It includes that part of the valve in which the plug is positioned for rotatable operation. FIGURES 2 to 6, inclusive, will be used in describing and making clear the cooperation of this portion of the valve, in reference to the plug already detailed.

In FIGURE 2, the plug seat means 32 is opened longitudinally to show the details of the internal structure. A flanged portion 5%) forms a connecting surface for the top 34. Threaded holes 52 register with like holes 58 in the cap to receive bolts, not shown. Normal practice dictates the use of a simple gasket between these two separable members of the valve body, and it is understood that such will be used, even though it is not shown here for purposes of clarity.

Inside the seat means, vertically spaced

horizontal channels

60 and 62 extend completely around the inside of the seating surface. Sectional FIGURES 3 and show this complete encirclement of these horizontal passages. Extending vertically between

channels

60 and 62, four

spaced channels

64, 66, 68 and 70, shown in FIG- URES 3 and 4 and indicated as being behind the sintered porous metal cover 72 in FIGURE 2, transmit liquid therebetween. Completing the structure in sectional FIG- URE 4, the inlet 74-, of same diameter as the aperture 36 in the plug, is diametrically aligned to transfer slurry to one limit of an arcuately spread outlet 76. Other positions of the plugaperture 36, relative to the vertical channels and the limits of the arcuately spread outlet, will be explained as part of the operation, Finally, in this FIGURE 4, there is shown the upper terminus of a connecting passage 78, adapted to feed liquid directly to the lower face of plug 36, at a certain point in the operating movement. Passage 78 does not connect with sintered porous metal cover 72, but channel 78 extends through the sintered porous metal cover to directly engage plug aperture 36.

FIGURES 5 and 6 show sections of the seat means, taken through two successively lower parts of the body. FIGURE 5, in addition to showing the full encircling of channel 62, shows the connection with a liquid feed passage 80. Feed passage 80 rises from the roof of an arcuate space 82. This space 82 is arcuately extended to transmit liquid to passage 80 during all portions of the arc of travel for plug between the open and closed positions. Connecting passage 78 receives liquid from transverse channel 38 only when the channel and passage inlet are aligned, midway between the open and closed positions. Washing liquid at a pressure higher than that existing at inlet 74 is controllably fed to the contact surfaces and the plug aperture, from the supply to the bottom of the seat means through aperture 84.

As stated above, the described valve is designed to transmit a slurry of comminuted material suspended in liquid. This is accomplished by directing a washing liquid to critical areas during the rotary movement of the valve plug from the open to the closed position, or vice versa. The following description of the operation of the disclosed valve is supported by all the figures of the drawing, and by the above-detailed description of. the cooperating elements.

Plug 36, as shown in FIGURE 2, is substantially in the open position, transferring slurry from inlet 74 to outlet 76, as indicated by the full lines in FIGURE 4. Transverse channel 38 in the bottom of plug 30, aligned with the plug aperture 36, is transmitting liquid from the liquid inlet 84 to the space or chamber 82, as indicated by dotted lines in FIGURE 6. From chamber 82, the pressured liquid is transmitted through passage 80 to the lower horizontal channel 62. From channel 62, the liquid circulates through

vertical channels

64, 66, 68 and 79 to upper horizontal channel 60. The lower horizontal channel 62 is separated from the plug 30 by the sintered porous metal cover 72, as shown in FIGURE 5. Similarly, the upper horizontal channel is separated from the plug by sintered metal cover 72, see FIGURE 3. Likewise, the

vertical channels

64, 66, 68, and 70 are covered by the sintered porous metal cover 72, see FIG- URE 4. The sintered porous metal covers 72 functions to permit the pressured wash liquid to seep therethrough, from the

channels

60, 62, 64, 66, 68, and 70 to the contact surfaces of plug 30. At the same time, cover 72 prevents leakage of the solids of the slurry outwardly from the plug surface into these channels, the pores of this cover being sufficiently small to prevent such leakage of solids. The

channels

60, 62, 64, '66, 68, and 70 are kept filled at all times with wash liquid; since as a result there are no voids in these channels, there is no appreciable tendency for the fluid portion of the slurry to pass outwardly from the plug surface into these channels. Thus, in the open position of the plug the pres- 4 sured wash liquid in the various horizontal and vertical channels seeps through the cover 72 into contact with the contact surfaces of plug 30. The pressure of the liquid, greater than the process pressure which the valve receives, prevents the solids of the slurry from lodging between the plug and the seat means.

As the plug 36 is rotated in a counterclockwise direction from the open position, toward the closed position the slurry passage aperture 36, aligned with channel 38, is moved to a position substantially that as shown in FIGURE 8. In this position, the receiving end of plug aperture 36 is in line with passage 78, which extends through the sintered porous metal cover, and the exit end is still in the arcuately spaced open area of body exit passage 76. Also, channel 38 in the bottom of plug 30 aligns liquid inlet 84 with the bottom opening of passage 78 (FIG. 7), transmitting a stream of pressured liquid into and then through plug aperture 36, in washing action. Solid slurry particles are washed clear of the plug passage. Due to the Wide arcuate spread of chamber 82, channel 38 is continuing to deliver pressured liquid behind the sintered porous metal cover 72 through the channel structure, also giving a washing action to the contact areas.

In the closed position, plug aperture 36 assumes the position shown in FIGURE 10. One end of this aperture is closed against the seat means wall and the other end is in contact with vertical channel 66 cover. Pressured liquid is still being delivered through passage 80 to the horizontal and vertical channel structure, and from there through the sintered porous metal cover to the plug contact area. As FIGURE 9 is oriented with FIGURE 10 and channel 38 is diametrically oriented with slurry passage 36 or the plug aperture, it will be evident that pressured liquid will fill chamber 82, passage 89 and the channel structure for all positions of the plug 30. It is only at the midway point between the open and closed positions that the pressured liquid is directed by channel 33 to passage 78 to wash the plug aperture 36 free of the slurry solid particles.

A preferred form of slurry control valve of the rotatable plug type is shown. Modifications of size, shape, relative proximity of the elements, and like changes, will be immediately evident.

I claim:

1. A rotatable plug valve for controlling the flow of liquid-supported comminuted solids forming a slurry, comprising a plug rotatable between open and closed positions, and vice versa, and transversely apertured to pass slurry therethrough in the open position, a seat for said plug having a restricted inlet and an enlarged outlet positioned to cooperate with said plug aperture, said enlarged outlet being coupled to said plug aperture, but said restricted inlet being uncoupled therefrom, at a plug position intermediate said open and closed positions; a circumferential channel in the plug contact surface of said seat, sintered metal cover means over said channel, conduit means connected to supply pressured wash liquid continuously to said channel, said cover means passing the wash liquid therethrough from said channel to the contact surface of said plug but rejecting the slurry solids, and a passage in said seat and plug operably controlled by said plug and positioned to direct a bath of pressured wash liquid from a point in said conduit means into said plug aperture at said intermediate plug position, said bath of liquid then flowing from said plug aperture through the enlarged outlet of said seat.

2. A plug valve as set forth in claim 1, including also limiting means cooperating with said seat for limiting the plug movement to travel between said open and closed positions.

3. A plug valve as set forth in claim 1, including an additional circumferential channel connected by longitudinal channels with said circumferential channel, said additional channel and said longitudinal channels all being in the plug contact surface of said seat, said conduit means also supplying pressured wash liquid continuously to said additional channel and said longitudinal channels; and sintered metal cover means over said additional channel and said longitudinal channels.

4. A plug valve as set forth in claim 1, including an additional circumferential channel connected by longitudinal channels with said circumferential channel, said additional channel and said longitudinal channels all being in the plug contact surface of said seat, said conduit means also supplying pressured Wash liquid continuously to said additional channel and said longitudinal channels; and sintered metal cover means over said additional channel and said longitudinal channels; said plug valve including also limiting means cooperating with said seat for 15 References (Jited in the file of this patent UNITED STATES PATENTS 331,531 Neracher Dec. 1, 1885 1,519,858 Lumley Dec. 16, 1924 2,318,638 Scott May 11, 1943 2,536,896 Wood Jan. 2, 1951 2,708,096 Mueller May 10, 1955 2,711,752 Schmidt June 28, 1955 2,734,523 Wiggans Feb. 14, 1956 2,774,363 Benzien Dec. 18, 1956 2,834,366 Bond May 13, 1958