US2670928A

US2670928A - Bearing assembly for oil well drilling turbines

Info

Publication number: US2670928A
Application number: US128841A
Authority: US
Inventors: George P Wagner
Original assignee: ENGINEERING DEV Co Inc
Current assignee: ENGINEERING DEV Co Inc; ENGINEERING DEVELOPMENT COMPANY Inc
Priority date: 1949-11-22
Filing date: 1949-11-22
Publication date: 1954-03-02
Anticipated expiration: 1971-03-02

Description

Mar 1954 G. P. WAGNER BEARING ASSEMBLY FOR OIL. WELL DRILLING TURBINES Filed Nov. 22, 1949 2 Sheets-Sheet. 1

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March 2, 1954 WAGNER 2,670,928

BEARING ASSEMBLY FOR OIL WELL DRILLING TURBINES Filed Nov. 22, 1949 2 Sheets-Sheet 2 BY George I? Way/zer- ATTORNEYS K Patented Mar. 2, 1954 BEARING ASSEMBLY FOR OIL WELL DRILLING TURBINES George P. Wagner,

Mount Vernon, N. Y., assignor to The Engineering Development Company, Incorporated, a corporation of Texas Application November 22, 1949, Serial N 0. 128,841

4 Claims.

casing and shaft have cooperating turbine blades forming a turbine unit which is operated by the drilling mud pumped downwardly through the drill stem to rotate the shaft. The shaft has -a bore openin at its lower end and communicating through holes with the interior of the casing at a point above the lower end but below the turbine unit.

During the operation of. such a device, there is always formed a substantial amount of grit and small pieces of stone in the bottom of the hole. This'cannot be entirely eliminated from the drilling mud, which is in practice recirculated through the drill stem and turbine. In addition, the lower end of the turbine unit on the outside is exposed to this grit.

The primary object of the present invention is to provide a bearing assembly for the lower end of the shaft of an oil well drilling turbine which is constructed to resist the entry of grit and thus towhave a longer life in use than ordinary bearings.

This bearing is located between the openings into the shaft bore and the bottom end of the shaft, and seals off at the bottom the space between the shaft and the casing. Therefore the bearin is exposed at both ends to the fluid under pressure, since the pressure on the outside of the casing at the bottom of the Well is substantially as great as that within the casing.

A further object of the invention i to provide a bearing which is exposed both to the pressure within the casing and to that outside the casing, or in other words to substantially equal pressures at both ends. 7

.Still another object of the invention is to pro- .vide a bearing assembly which can be readily filled with lubricant, this lubricant through its incompressibility resisting the substantially balanced inward pressures of the drilling mud at both ends and therefore resisting displacement out of the bearing.

An additional object of theinvention is to. provide a bearing assembly which can be readily put together outside the turbine and then slipped into pIacewithout the use-,of-special tools or equipment.

sun another btjet bi assessor-1 is to provide a bearing assembly in which the various parts can be completely filled with lubricant without removing th hearing from the turbine, and without disassembling the turbine.

Further objects and advantages of the invention will appear more fully from the following description, especially when taken in conjunction with the accompanying drawings which form a part thereof.

In the drawings:

Figs. 1A and 1B show in cross-section a bearing for the lower end of the oil well drilling turbine embodyin my invention;

Figs. 2 to 5 are cross-sections on the lines 22 to 55 respectively of Fig. 1A; and

Fig. 6 is a cross-section on the line 66 of Fig. 1B.

The invention as shown in the drawings is particularly intended for use in connection with an oil well drilling turbine described in my previous application S. N. 729,613, filed February 17, 1947.

That application described a construction in which the turbine drive shaft, which is to carry the drill bit, is arranged within a casing formed of an outer shell or casing and an inner sleeve made up of a plurality of parts which can be assembled together and thereafter slid into the outer casing. The stator blades of the turbine are arranged on parts of this sleeve, and are interlocked with each other and with the succeeding sleeve parts. The present invention constitutes an improvement on the lower bearing shown in that application, this bearing supporting the shaft in axial relation with and supporting it to turn within the outer casing. The bearing structure is however, adaptable to other types of oil Well drilling turbines.

The construction as shown in the drawings includes a shaft 2 which is to carry the rotor blades, a casing member 4 and a sleeve. The sleeve in-- cludes a bearing part 6 and a spacing part 8, this spacing part 8 in turn being intended to be interlocked with the rings carrying the stator blades. The shaft 2 has a bore in therein opening in the lower end through a threaded member l2 to which the drill bit is to be attached. Holes [4 open from the outside of the shaft into the bore [0 at a point above the bearing sleeve part 6, opposite the spacing sleeve part 8.

The sleeve part 6 is internally threaded at both ends to receive holding nuts [6, and has intermediat its length an inwardly directed shoulder [8. The nuts It and the shoulder l8 are of slightly greater internal diameter than the ex- 3 ternal diameter of shaft 2. Against the shoulder l8 and just above it abuts a bearing 26 which may be a sleeve of bronze or other suitable material. This bearing has on its inner face grooves 22 running its full length.

Above the bearing and th sleeve 20 and below the shoulder l8 are arranged packing members. Each packing is composed of a male member 24, a set of packing rings 26, a female member 28, another set of packing rings 30 and a male member 32. The upper packing is spaced from the hearing by a spacing sleeve 34. The male members 32 are engaged between holding nuts 10.

Each of the female members 28 has a circumferential groove 36 in its outer face and holes 38 opening through the female member and into the space between this member and the shaft. Sleeve member 6 and outer casing 4 have aligned holes opening into th grooves 36, these holes being closed by removable threaded plugs 40. Spacing sleeve 34 also has a peripheral groove :22 and holes 33 opening from this groove into the interior of the sleeve. Aligned holes in the outer casing '4 and sleeve section b communicate with groove 42 and are closed by threaded plugs it. There are also at shoulder l8 aligned holes opening at '18 "into the space between the shoulder and the shaft and closed by threaded plugs 50. The retaining nuts it have holes 52 therein for operation by a suitable tool. A nut 54 is threaded into the lower end of the outer casing 4 and abuts the lower retaining not It, so as to hold the packah'd bearing assembly within the outer casing. The sleeve part 6 is keyed as at 56 to the outer casing "4 so as to prevent it from turning therein.

Sleeve section 3 has projections 53 engageable in corresponding notches in the upper retaining nut 1'6. The edges or these notches and projections are radial to the axis of the shaft. As a result, the sleeve section 8 is not only locked against turning with respect to the bearing assembly, but is also prevented from moving laterally with respect thereto, this arrangement holding the parts properly aligned during the sliding of the outer casing '4 over the sleeve during the assembling of the device.

In the use of the turbine, the various packin'gs and the spaces between the spacer ring 34 and shoulder 18 and the shaft are filled with lubricant before the operation begins. Thorough filling may be achieved by introducing the lubricant tl'nough the openings of plugs 40, and allowing it to escape through those of plugs 45 and 50. This insures that a thorough filling of the whole bearing has been accomplished. The channels or grooves 22 in the interior face of the "bearing also allow communication lengthwise of the bearing unit, so that the pressures of the lubricant are equalized throughout the unit.

When the turbine is used in the drilling of the oil well, it is operated by the mud which is pumped downwardly through the well. This mud after passing by the turbine enters the space between the sleeve part 8 and the shaft '2, and then through hole 14 and passage l0, escapes through "the drill bit and proceeds back upwardly past the outside of the turbine. This mud is under considerable pressure, since the hydraulic static pressure alone at 10,000 feet amounts to 5,000 pounds per square inch. 'There is "therefore a tendency for the fluid to press past the packing rings 30 and to get into the hearing, where the sand and grit which is inevitably present in such mud would do serious damage and would quickly wear out the bearing. However the pressure outside the unit is almost equal to that inside, and this pressure is exerted upwardly through the space 60 between nuts 54 and I6 and the shaft, and operates upon the lower packing rings 30. Thu substantially equal pressure is exerted at both ends against the packings. Since the whole space between the bearing unit is filled with lubricant, which is substantially incompressible, there is no displacement of the lubricant from the bearing. Even leakage of fluid past packing rings 30 is not likely to reach the bearing and cause damage, since the lubricant is substantially incompressible and is being subjected to an equal pressure at the other end. Under these conditions, the pressure of the mud then tends in effect to hold the lubricant in the bearing and to prevent its displacement by the drilling mud which might cause damage.

In assembling the device, the whole bearing unit including the sleeve section 6, the parts enclosed in it and the holding nuts I5, is assembled as a separate part. During the assembling of the turbine, as directed in my prior application, the various sleeve sections are successively assembled in the shaft, this bearing unit constituting one of the sleeve sections and by the interlocking of the sections any rotational or lateral movement between them is prevented. When all the sleeve parts are asembled, the outer casing 4 is slid on, engaging the key 56 so as to lock the sleeve against rotation within the outer casing. Nut 5a is then applied, and the turbine is ready for use.

While I have described herein one embodiment of my invention, I wish it to be understood that I do not intend to limit myself thereby except within the .scope of the claims hereto or hereinafter appended.

I claim:

1. A hearing unit for an oil well drilling turbine having a casing and a shaft turnable therein, comprising a sleeve bearing mounted in the casing and engaging the surface of the shaft, packing members between the casing and the shaft above and below the bearing, and a spacing member between the upper packing and the bearing, said spacing member comprising a sleeve having a peripheral groove in .its outer face and holes through its wall connected to said groove, said "casing having an opening therethrough connected with said groove, and removable closure means for said opening.

2. A bearing unit for an oil well drilling turbine having a casing and a shaft turnable thereiii comprising a sleeve bearing mounted in the casing and engaging the surface of the shaft, packing members between the casing and the shaft above and below the bearing, said casing having an opening theret'hrough into said packings, removable closures for said openings, each of said packings including an intermediate ring member and packing rings 'on opposite sides thereof, said ring member having a peripheral groove in its outer face and holes through its walls connected to said groove, said packing openings -comrrmnicating with sa'id grooves.

3. A bearing unit for an oil well drilling turbine having a casing and a shaft turnable therein, comprising a sleeve bearing mounted in the casing and engaging the surface of the shaft, packing members between the casing and the shaft above and below the bearing, said bearing 15 having a groove in its inner surface forming a lubricant passage connecting opposite ends of the bearing, said casing having an opening therethrough into said packings, removable closures for said opening, a spacing member between the upper packing and the bearing, said casing having an internal shoulder between the lower packing and the bearing, the bearing abutting against said shoulder, the internal diameter of the shoulder being greater than the external diameter of the shaft, said casing having a second opening from the outside thereof into the space between the shoulder and the shaft, removable closure means for said second opening, each of said packings including an intermediate ring member and packing rings on opposite sides thereof, said ring member having a peripheral groove in its outer face and holes through its walls connected to said groove, said packing openings communicating with said grooves.

4. In a device as claimed in claim 2, said spacing member comprising a sleeve having a peripheral groove in its outer face and holes through its wall connected to said groove, said casing having an opening therethrough connected with said groove, and removable closure means for said opening.

GEORGE P. WAGNER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,482,702 Scharpenberg Feb. 5, 1924 2,137,328 Bissell Nov. 22, 1938 2,165,916 Bissell July 11, 1939 2,167,019 Yost July 25, 1939 2,320,589 Gruetjen June 1, 1943 2,350,364 Menhall June 6, 1944