SU1761936A1 - Device for rolling cutter bit bearing sludge protecting and lubricating - Google Patents

Abstract

Use: drilling with roller bits with the cleaning of the intake air-water mixture. SUMMARY OF THE INVENTION: The device includes a housing placed between a drill rod and a roller bit. Two spring-loaded non-return valves are installed in the body cavity, one of which is designed as a piston, and the other as a plate connected to it. The valve seat is designed as a sleeve with radial channels and longitudinal channels connected to them. When the device is triggered, the radial channels overlap the piston and the longitudinal channels overlap the plate. 1 il.

Description

The invention relates to the drilling of wells in quarries with roller cone bits with a bottom-hole mixture cleaning and can be used to drill watered wells.

There are known devices for sludge protection and lubrication of roller bit supports, which are installed directly in the bit nipple and blocking both the central blowing hole in the bit nozzle and the annular cavity of the bit nipple during blowdown shut-off.

A disadvantage of the known sludge protection devices installed in the nipple of the roller bit is that, in connection with the limited working space in the nipple of the chisel, the sludge protection device accepts the minimum dimensions of flow sections for the passage of the washing-blowing and lubricating agent.

As a result, when devices are operated in a pneumatic transport network, pressure increases, which causes unnecessary energy costs, and reduces the service life of the pump-compressor equipment.

The noted deficiency is partially eliminated in the sludge protective device, in which non-return valves are installed in adapters above the bit. It contains upper and lower adapters connected to each other by the drill pipe, and is equipped with two valves, one of the valves overlaps the cavity formed between the adapters from above, is spring-loaded relative to the upper adapter and is connected by a rod with another valve fixed in the lower adapter .

However, this device does not provide reliable sealing of sealed polos (L

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First, due to the fact that in both the upper and lower valves, the sealing of the insulated cavities is carried out along a very narrow strip of contact between the valve and the valve seat.

It is known that if the size of the valve contact strip with the valve seat in the direction of leakage is L, the width of the gap in the seal S and the average leakage rate VCp, the leakage of compressed gas with dynamic viscosity c will occur when the pressure drop A / and L Vcp / S1, those. this will be the maximum overpressure that can be kept in the cavity to be sealed with the contact strip width L in one valve.

With two valves isolating the cavity from both ends, as is the case in the prototype, the leakage of compressed air will be twice as intensive and will occur mainly through the upper valve, since it is here that the pressure drop will be greatest.

It follows that it is especially necessary to seal the leakage channels in the upper valve.

Secondly, in the working position, the valves connected between themselves with a thin and long rod (about 8 m) are centered only in the upper sleeve, which is freely located in the recess of the adapter, therefore, when drilling under conditions of lateral beats and intense vertical vibrations of the rods , the valves will swing like a master, which will necessarily damage the sealing surfaces of the valves and their nests in the very first period of penetration so that the sealing of the cavities will become impossible.

Thirdly, the upper and lower adapters, which are made integral with valve sockets, are rigidly connected between each other by a drill pipe (about 8 m long) with threaded connections on each ring.

Practically achievable tolerances of the coaxiality of the holes (valve sockets) relative to the longitudinal axis with such removal are 2-3 mm, and the deviation from the coaxiality of the holes in the valve sockets, required to ensure reliable sealing, should not exceed 0.02-0.03 mm, t. e. less than 100 times.

Another disadvantage of the prototype is the increased aerodynamic drag that occurs when the flushing-blowing agent is skipped due to excessive shading of the flow sections in the upper adapter caused by the need to install the centering sleeve mentioned above. In addition, it has an increased material consumption of parts of the device.

5 The purpose of the invention is to increase the reliability of sealing of insulated cavities and increase the performance of the device.

The goal is achieved by the fact that

10 in the device containing the adapter, the nipple of which is connected to the drill rod, and the coupling to the bit, valve seat installed in the nipple part of the adapter, and two valves spring-loaded

15 relative to the adapter, the valve seat is made in the form of a sleeve with radial and longitudinal channels connected to them, and the upper and lower valves are combined into one piece, made in the form

0 piston with a plate at the lower end installed in the sleeve with the possibility of blocking its channels.

Distinctive features of the invention are the implementation of the nest of valves in the form of a sleeve with radial and connected with them longitudinal channels;

combining the upper and lower valves into one single piece, made in the form of a piston with a plate at the lower end, installing this part in a sleeve with the possibility of blocking its channels.

This solution allows you to double the possible leak paths.

5 compressed air from the sealed cavity of the nipple of the bit and the mills using simple valves, which include a cylindrical piston and a flat poppet valve.

0 Combining the upper and lower valves in one piece, made in the form of a piston with a plate at the lower end, allows to produce this part with high accuracy, maintaining the required tolerances on the cycling, and perpendicularity of the arrangement of sealing surfaces, when installed in the above the valve seat ensures very strict centering of parts and increased reliability of sealing of isolated cavities both due to double overlap of possible leakage paths in the direction of the upper valve and due to you ora desired size L-valves with contact strips kla5 pannym receptacle in the leakage direction.

The invention allows to reduce the consumption of materials and the aerodynamic resistance of the device during the blowing of wells. The invention can be used not only in valves of sludge protective devices, but also in other designs of machines and mechanisms, in pneumatic and hydraulic systems where increased reliability of sealing of insulated cavities is necessary.

Parts of the device are simple in shape and easy to manufacture.

The drawing shows a general schematic diagram of the device.

It includes adapter 1, the nipple of which is connected to the drill stand 2, and the coupling to the roller bit 3, valve seat installed in the nipple part of adapter 1 and made in the form of sleeve 4 with radial channels 5 and longitudinal channels 6 connected to them. Inside the sleeve 4 there is a part 7, which unites two valves: the upper one, made in the form of a cylindrical piston 8, which overlaps the radial channels 5 of the sleeve 4, and the lower one - the disk valve 9, which blocks the longitudinal channels 6.

Spring 10 valves are pressed to the lower end of the sleeve 4.

To pass the flushing and blowing agent out of the subvalvular cavity 11 to the roller bit 3, the adapter 1 has axial 12 and peripheral holes 13, and the central nozzle 14 and channels 15 are provided in the roller bit 3 for blowing the roller cone supports.

The proposed device operates as follows. The mechanism of rotation of the machine rotates the drill becoming 2 and the adapter 1 and the roller bit 3 connected to it, pressing it to the bottom of the recessed well. Rolling over the face, the bits of the bit cutters destroy the rock. A water-oil-air mixture (flushing-blowing agent) is injected into the drill rod 2 from the pump-compressor unit of the machine. The mixture, the passage through the pipes of the drill rod 2, presses on the upper end of the piston valve 8 and shifts it downward, compressing the spring 10. Moving down, the valve 8 opens the radial channels 5, and the poppet valve 9 opens the longitudinal channels 6, therefore the mixture

the flushing and flushing agent enters channels 5 and 6 into the subvalvular cavity 11, and from it holes 12 and 13 enter the nipple of the roller bit 3 into the cavity. Here the mixture flow is separated and part of it (approximately 70% of the total volume) through the central the nozzle 14 goes to the bottom to clean the well, and the other part of the channels 15 enters the roller cone supports for cooling and lubricating the bearings. This is the operating mode of cleaning the well and associated lubrication of the supports.

In the event of a sudden shutdown of the purge, the pressure of the mixture in the drilling rig 2 decreases and the spring 10 is compressed and presses the disc valve 9 to the valve seat 4, while the disc valve 9 blocks the mouth of the longitudinal channels 6 and the piston valve 8 at the same time closes the radial channels 5 leading the internal cavity of the valve socket 4.

Thus, channels 5 and 6, which communicate the internal cavity of the drill rod 2 with the cavity of the nipple of the bit 3 and the annular space of the well, are blocked twice, which ensures reliable sealing of the insulated cavities and keeps the pressure of the flushing-blowing agent equal to the pressure that preceded the shutdown of the purge, therefore, neither the sludge nor the contaminated liquid can penetrate either the bearings of the cones, nor into the nipple of the bit 3, nor into the subslap cavity 11 adapter 1.

When resuming the blow, the order of operation of the sludge protective device will repeat in the sequence described above.

It should be noted that the proposed device not only reliably seals the insulated cavities, but also separates most of the liquid and lubricant contained in the part of the mixture that goes to the center of the bottom, and directs the separated liquid and lubricant to the cones.

This is due to the fact that the flow of the mixture entering the internal cavity of the nest of 4 valves is divided into 9-12 parallel streams (according to the number of longitudinal channels 6). The movement of the mixture undergoes a high degree of turbulence. Liquid droplets and lubricants collide with each other and combine, stick to the walls of the channels 6 and flow down them into the subvalvular cavity 11.

Following to the nipple of the bit 3, the flow of the mixture re-passes through the apertures 13 and is again dried. This leads to the fact that at the walls of the device there is a mixture of a purge agent enriched with liquid and lubricant, and in the central part dried air flows. From the nipple of the bit 3, the mixture enriched with liquid and lubricant flows through the channels 15 into the bearings of the cones.

The water-oil-separation process can be significantly enhanced if a oil-separating tube or valve, for example, KOP-2, is screwed into the central nozzle 14. The proposed device does not exclude this possibility.

Claims (1)

The invention The device for slam protection and lubrication of roller bit supports includes a hollow body placed between a drill rod and a bit and two spring-loaded non-return valves installed in the body cavity, characterized in that, in order to increase its reliability due to better stabilization valve displacement at od0 a modern decrease in their metal content, check valves are made in the form of a piston with a plate at the lower end, and the valve seat is in the form of a sleeve with radial and longitudinal channels connected to them, while the piston is installed in the axial channel of the sleeve with the possibility of blocking its radial channels, and the plate - with the possibility of blocking the longitudinal channels. 15