US2336173A

US2336173A - Service t

Info

Publication number: US2336173A
Authority: US
Inventors: Henderson Elting
Original assignee: Individual
Current assignee: Individual
Priority date: 1942-06-29
Filing date: 1942-06-29
Publication date: 1943-12-07
Anticipated expiration: 1960-12-07

Description

Dec. ,7, 1943. HENDERSON SERVICE TEE Filed June 29, 1942 Patented Dec. 7, 1943 UNITED STATES PATENT OFFICE SERVICE VT Elting Henderson, Whittier, Calif. Application June 29, 1942, SerialNo. 448,979-

2 Claims. (Cl. 251-43) The present invention relates to an improved service T arranged to be interposed between a fluid pressure main and a branch or service pipe, for conducting gas, water, oil, and other fluids from the main to the service pipe, and is more particularly directed to the association with the service T, of a combined plugging unit and tool guide. The present application is a continuation-in-part of my copendin'g application Serial No. 410,632, filed September 12, 1941.

An important feature of the invention consists in providing the bore of the T with an integral web or partition member which is formed with a reduced axially disposed openingof such length and diameter relative to the drill or'a center cating punch, that the wall of the reduced opening acts to constitute an axially disposed guide to insure both the drill tool and the punch, when inserted into the T, being maintained in proper operative alignment relative to the part of the main to be tapped. The wall of the opening in the web also ccacts with the drill to prevent the latter from crawling on the main during the drilling operation. The top or upper surface of the web is formed to provide a seat for the end of a movable plug or stopper which is permanently inserted within the T after the drilling operation is completed. This plug is normally adjustably maintained in a position above the web so as not to interfere with the free flow of the fluid through the T. However, in the event it becomes necessary to cut off the supply to the service line or pipe, this may quickly and easily be done by moving the plug in engagement with its seat.

A further object is to provide an improved apparatus for controlling the flow of the fluid through the T. This is effected by associating with the valve seat in the T, means including a hollow plug or cylinder having its inner and outer surfaces provided with threads of different pitch, which coact with complementary'formed threads on the inner wall of the T and the outer surface of the stopper, to move the stopper axially relative to its seat. The differential threaded plug is also arranged when rotated relative to the stopper when the latter is initially moved against its seat, to exert an increasing downward pressure on the stopper due to the difference in pitch of the threads, to insure the stopper being maintained in tight sealing engagement with its seat when the fluid supply is cut off.

Other objects and advantages of theinvention will become apparent from the following description, when taken in conjunction with the accompanying claims and drawing.

Referring to the drawing, in which are shown several preferred embodiments of the invention:

Figure 1 is a vertical sectional view of the T and the main to which it is applied, and shows a part of a drilling tool associated therewith.

Figure 2 is a vertical sectional view of the T showing a plugging unit associated therewith.

Figure 3 is a detail vertical sectional view of the upper portion of. the T showing the stopper in its raised'position.

Figure 4is a plan view of Figure 3.

Figure 5 is detail vertical sectional view of a modified form of the invention, and

Figure 6 is a plan view of Figure 5.

Referring to the drawing, in which like numerals indicate like parts in the several views, It designates the body of a service T which is connected to the fluid pressure main H, such as a gas pipeor the like, in any suitable manner, such as by having its lower or inlet end welded as at lZto the main; Prior to the connection of the T l0, it is preferably preformed with an axial bore l3 and a lateral port' or outlet I4 to which the service line or pipe, not shown, is suitably connected.

The T l0 may be of solid steel forging and is bored inwardly from each end thereof a specified or predetermined distance, to form the elongated integral web or partition l5, which preferably extends from the lateral port I4 downwardly'to a point adjacent the main II to provide the bore with a lower or inlet section l6 and a spaced upper section ll. The solid web 15 is then drilled to provide the reduced axially disposed elongated opening 18 so as to establish communication of the inlet section IS with the upper section I! and the outlet port M. The upper end of the T H] has an externally threaded portion l9 and an internally threaded portion 20.

The preformed T if) is initially installed at the: point where the branch line or service pipe is to be attached to the main, and a drilling apparatus such as shown in the Mueller Patent No. 1,996,345, April 2, 1935, may then be connected to the Tim order to tap the main. The fitting 21 of the drilling apparatus is internally threaded at its lower end so as to be connected as at 22 to the'externally threaded portion l9 of the T.. The elongated drill 23 which is con. nected as at 24 to the rotatable operation rod 25, is then inserted through the fitting 2i and into the T toform the opening 26 in axial alignment with the bore l3. The reduced opening l8 preferably extends from the outlet 14 to a point adjacent the inlet ofthe bore, and is of such a length as to overlap a major portion of the tool inserted therein, in order to serve as a guide to hold the shank of the tool steady during the drilling operation.

The reduced opening IS in the web i5 is accurately machined or formed to provide a small tolerance or clearance between the wall thereof and the drill. It will be manifest that if there is too much clearance between the drill and the wall of the opening IS, the wall would not constitue a guide means or bearing surface which would insure proper alignment of the tool with the main during the tapping operation. For; this reason, the clearance between the tool and drill not infrequently has been broken in the T due to the excessive strains to which it was sub ject'ed during the drilling o'peration. By virtue of the small clearance between the wall of the opening I 8 and the drill, it will be seen that positive, efficient and economical means are provided for guiding and maintaining the drill in proper alignment with the T' when drilling a hole in the main and which also prevents crawling of the drill on the main. The upper surface of the web 15 at the juncture of the section I! with the reduced opening I8, is preferably formed with a seat or tapered portion 2?, the purpose of which will be subsequently described.

Prior to the attachment of the drilling apparatus to the T to tap the main ii, a center 10- cating punch such as shown in the Mueller application, Serial No. 315,825, filed January 26, 1940, may be introduced into the T to form an indentation in the outer wall of the main to insure the opening being formed concentric with'the bore of the T. The diameter of the centering punch is substantially the same as that of the'drilling too-1 23 so that the wall of the reduced opening l8 will insure the punch being maintained in proper axial alignment with the bore of the T. Upon the removal of the punch or indenting tool from the T, the fitting 2| and its associated parts are connected to the upper portion of the T so that the drill 23 may 2 to back up or turn the latter in a counterclockbe rotated and moved axially into engagement with the indented portion of the main, and thus insure the drill 23 being positioned and maintained concentric with the drilling apparatus and the bore of the T during the tapping operation.

After the opening 26 is formed in the main, the drilling apparatus is removed from the plugging unit is permanently positioned within the upper section ll of the bore. This plugging unit comprises a hollow removable closure member or brass plug 28 which is externally threaded. as .at-29, to engage the complementary internal threads 23 on the T. The closure member 28 also has an internally threaded opening 33 concentrically disposed relative to the axis of the bore i3 of the T. The wall of the opening 33 is arranged to receive and guide the upper threaded portion or stern 3! of an adjustable stopper or plug 32, preferably made of steel; and which is inserted within.

the T after the-opening. 26 hasbeen forined in the main, in order to provide mcan's' fi1r'con'-..

trolling or outing. off the fio'w of the fiuidsuri-f ply from the main to the service pipe when'i't'.

I-Ieretofore in devices of this character,-

;' seat 21.

ter. The stopper 32 is relatively short and is preferably formed with a tapered lower end portion 33 arranged to extend a limited distance within the openinug H! of the web and engages the seat 21 when it is necessary to cut ofi the flow of the supply of the surface line so as to form a tight sealing engagement therewith. The top of the stem or portion SI of the stopper 32 may be provided with a kerf or recess 34 which receives a suitable tool, such as a screw-driver or the like, so as to control the axial position of the stopper 32 relative to the The stopper 32 is preferably formed beneath the threaded stem 3! with a tapered P inserted in the kerf 3Q.

shoulder 35 arranged, when the stopper is raised to its full open position, to engage the lower end of the opening 38 in the plug 28 (Fig. 3) in order to prevent leakage of the fluid therethrough. The upper end of th plug 28 extends from the T and has a reduced portion or head 36 of any'polygonal shape for receiving a tool such as a wrench, so as to apply Or remove the plug from the T.

When the stopper 32 is moved downwardly against its seat 2? to cut ofi the flow of gas through the T, it has been found that it is not possible to apply sufiicient pressure on the stopper by a screw-driver inserted in the kerf 34, efiectively to seal the gas flow through the T. Accordingly, the threads 23 and their coacting threads 29 on the plug 28 are of different pitch than the threads 30 and their coacting threads 3! on the stopper 32. As shown in Figure 2, the threads 2023 are I l-pitch, While the threads 33-3! are 13-pitch. The internal threads on the plug 28 and their coacting threads on the stem of the. stopper 32 may be of greater or less pitch than the external threads on the plug and their coacting threads on the T.

When it is desired to out ofi the flow of the gas through the T, the stopper 32 is rotated clockwise as shown by the arrow A in Figure 4 so as to be forced downwardly as tightly as possible against its seat 2'! by a screw-driver or th like, This pressure alone would not be suilicient to insure the stopper being maintained in sealing engagement with its seat. Therefore, a suitable tool, such as a wrench, is applied to the head 33 of the plug 28 wise direction (arrow B, Figure 4), whichtends to unscrew the plug 28 from the T 53 at the rate of /14" per revolution. Since the internal threads 30 and their coasting external threads 3! on the stem are /13 pitch, it will be seen that,

due to the differential effect of the pitch of the threads 23-29 and 3il3l, the plug 23 will tend to come off or be removed from the stopper 32 at a faster rate than it can be unscrewed from the T l3, with the result that the plug 28 exerts a downward increasing thrust or pressure on the stopper 32 equal in effect to a fine thread, the equivalent of the diff rences in the pitch of the threads 25-29 and 33- --2!. Thus, positive means are provided to insure the stopper being held against its seat irrespective of the pressure of the fluid in the main. Moreover, since the head 36 of the plug 28 may be engaged b a wrench'or other tool having a good leverage, a much greater force can be exerted on the stopper to insure the latter being moved and maintained in; tight sealing contact withits seat 21.

. lnthe modification shown inFigures 5 and 6, thg pitch of thethreads are reversed to that previously disclosed. ln other'words, the external threads 31 on the plug 38 and their complementary internal threads 39 on the inner wall of the T 40 are of l3-pitch, while the internal threads 4| of the plug and their coacting external threads 42 on the stem of the stopper 43 are of i l-pitch.

To cut off the flow of the fluid from the T 40, the stopper 43 is initially turned in the direction of the arrow C (Figure 6) so as to be forced in engagement with its seat, by a tool inserted in the kerf or opening 44 sufiiciently tight so as not to be rotated when the plug 38 is moved relative thereto. After the stopper has been seated, a suitable tool is applied to the head 45 of the plug 38 and the latter is rotated in a clockwise direction or the same direction in which the plug has been turned, as shown by the arrow D in Figure 6, to engage its seat, in order to exert a downward increasing pressure on the stopper due to the difference in pitch of the threads, and thus insure the stopper being firmly maintained in sealing engagement with its seat. It will be noted that the only substantial difference between the threaded arrangement shown in the form of the invention disclosed in Figure from that shown in Figure 2, is that in the former the plug is rotated in a counterclockwise direction, or opposite to the direction or rotation of the stopper while in the latter it is turned in the same direction to force the stopper against its seat.

In both forms of the invention, the flow of the fluid through the T is controlled by, first, threading the stem of the stopper to the plug, then inserting the plug and stopper into the T so that the plug is threaded to the T above the valve seat. While, normally, the stopper is moved away from its seat to allow the free flow of the fluid through the T, it will be seen that upon the stopper being moved downwardly by a suitable tool, it will be brought into sufficiently tight engagement with its seat, as to be prevented from rotating with the plug when the latter is turned to increase this downward pressure. The plug is then either turned in the same direction or in the opposite direction to that of the stopper, depending upon the pitch of the threads, and is moved relative to the stopper to exert an increasing downward pressure on the stopper due to the difference in pitch of the threads, which further acts to provide sufficient lock-off pressure to insure the stopper being accurately and firmly seated against its seat so as to be capable of withstanding the pressure of the fluid to which Ts of this type are normally subjected.

It will be understood that the several forms of the invention and method for controlling the flow of the supply through the main are merely illustrative of preferred embodiments, and that such changes may be made without departing from the spirit of the invention, as come within the purview of one skilled in the art and the scope of the appended claims.

I claim:

1. A T for connecting a fluid pressure main to a service pipe, said T having an axial bore and a lateral port and provided with an internally threaded end portion, said bore having a web provided with an axial opening and a seat, a stopper in the T arranged to engage said seat to cut off the flow of the fluid through the T, said stopper having an externally threaded stem, an externally threaded plug connected to the threaded portion of the T and having a central threaded opening connected to the threaded stem of the stopper, the internal threads on the plug and the external threads on the stopper being of different pitch than the external threads on the plug and the internal threads on the T, said stem having means for receiving a tool to move the stopper into and out of engagement with said seat, said plug having a tool receiving portion whereby when the stopper has been initially moved in firm engagement with its seat, and the plug is rotated relative thereto, the movement of the plug acts to exert a downwardly increasing pressure on the stopper due to the difference in pitch of the threads to insure the stopper being maintained in tight sealing engagement with its seat, and means on the stopper for engaging the wall of the opening in said plug when the stopper is moved away from said seat, to prevent the escape of fluid through said opening.

2. A T for connecting a fluid pressure main to a service pipe, said T having an axial bore and a lateral port and provided with an internally threaded end portion, said bore having a web provided with an axial opening and a seat, a stopper in the T arranged to engage said seat to cut off the flow of the fluid through the T, said stopper having an externally threaded stem, an externally threaded plug connected to the threaded portion of the T and having a central threaded opening connected to the threaded stem of the stopper, the internal threads on the plug and the external threads on the stopper being of different pitch than the external threads on the plug and the internal threads on the T, said stem having means for receiving a tool to move the stopper into and out of engagement with said seat, said plug having a tool receiving portion whereby when the stopper has been initially moved in firm engagement with its seat and the plug is rotated relative thereto, the movement of the plug acts to exert a downwardly increasing pressure on the stopper due to the difference in pitch of the threads to insure the stopper being maintained in tight sealing engagement with its seat, and said stopper having a tapered shoulder arranged to engage the plug to close the opening therein, when the stopper is moved to its full open position.

EL'IING HENDERSON.