DE3726014A1 - High-pressure deep-hole hammer drill, for example for injection holes - Google Patents

Abstract

Published without abstract.

Description

The invention relates to a deep hole drilling hammer integrated with a special valve combination nation, which enables greater drilling depths in the Water or with a large water inlet. This valve combination exists

• 1. from an absolutely tight setback valve and
• 2. with one or more injector drive nozzles built-in check valves.

Injection drilling was previously only possible

• 1. with the core drilling method low drilling progress, expensive tools and great wear in hard rock
• 2. with the roller chisel also little drilling progress and high tool costs
• 3. with rotary drill bits can only be used in soft rock. The disadvantage of this method is the deviation the specified drilling direction and the roughness the borehole wall, which in turn destroys the

packer required for the injections.

Deep hole rotary hammers offer the advantage of directional accurate holes of high quality and almost the same permanent drilling progress. They are from the Bohr machine via an extension rod with compressed air operated from the front of these hammers or  from holes in the percussion drill head as blow-out air emerges again. The annulus created during drilling from the difference in diameter of the impact drill and drill hammer serves as a transport channel for the cuttings, whereby the exhaust air is used as the expulsion medium.

These hammers are z. B. to Drilling blast holes up to a depth of approx. 100 m used. Drilling through damp and water The formations are up to a maximum, depending on the water supply 50 m depth possible, but only with hammers Raise additional purging air, as through the Back pressure of the water-drilling mixture in the annulus the hammer mechanism between the drill pipe and the borehole wall after a few centimeters of drilling progress to a standstill comes and only after lifting the boom and blowing out for a few minutes.

Experience with additional blow-out holes in threads only have nipples between hammer drill and drill pipe success shown until the next boom change, because the unpressurized water drilling mix from penetrates outside into these blow-out holes, the drill hammer dirty and therefore inoperative.

The purpose of the invention is to remedy this, to take advantage of the deep hole hammer system, with a high-pressure deep hole hammer drill with Upper part or valve integrated elsewhere combination to achieve greater drilling depths.  

This valve combination exists

• 1. from a tightly closing check valve above the Bohr hammer control with a self-centering valve cap, the Sealing ring arranged concealed, opposite ball and surface offers the greatest possible protection against damage and absolutely lute tightness guaranteed. This valve cap on a valve Sliding lower part with spring chamber, prevents that possibly Fragments of the compression spring get into the hammer drill, as well soiling is almost impossible. The setback valve prevents water and cuttings from entering the hammer drill side into the hammer drill
• 2. from one or more injector propellant nozzles with kickback valves equipped and above the Ven are arranged. The air throughput of these propulsion nozzles is included to determine the size of the nozzle bore or its number. This nozzle bore is cylindrical at the outlet end and inwards widened conically to increase the air speed tet trained. The check valve in the injector nozzle prevents when changing the drill pipe, i.e. in the unpressurized Condition of the system, penetration of the water-drilling mix from the rod side into the hammer drill. The valve cone with compression spring, sliding in a spring chamber, ge guarantees against ball or plate valves susceptible to failure absolute tightness and insensitivity to dirt.

When the compressed air supply is opened, it causes air pressure injector drive nozzles with over 50% increased air speed escaping air jet that the sluggish water-drilling mixture is released whirls and is thrown out of the borehole at high speed is changed. The vacuum created below the injector nozzles is released the hammer from the disturbing back pressure and gives the relaxed exit the blow-out air again the necessary lift speed. The blow werk starts working immediately and an undisturbed drilling becomes guaranteed.  

Figs. 1-3 are cross-sectional drawings of a misfiring during lifting of the drill string downhole drilling hammers, combined while Fig. 4 with Fig. 1 illustrates a continuously striking hammer. In these sectional drawings, the right half is executed with the valves open in the working position and the left half in the rest position, i.e. in the depressurized state, with the valves closed.

Fig. 1 is a section through a hammer drill lower part with percussion drill 1 , front housing 2 , percussion piston 3 , cylinder 4 and cylinder insert 5th

Fig. 2 is a section through a center drill part with cylinder 4 , cylinder insert 5 , hammer control 6 , double nipple 7 , connecting slide piece 8 and hammer upper part 9th

Fig. 3 is a diagrammatic section through a hammer-shell with terminal sliding piece 8, damping ring 10, connection-threaded piece 11, the check valve part 12, compression spring 13, the valve cap 14, sealing ring 15, valve seat 16, domed strainer 17, threaded nipple 18, Injector drive nozzle 19 (closed), injector drive nozzle 20 (open), compression spring 21 , valve cone 22 and strainer 25 .

Fig. 4 is a sectional view of a continuously striking top hammer with cylinder 4 , cylinder insert 5 , control top 24 , compression spring 13 , valve cap 14 , sealing ring 15 , hammer top 23 , injector driving nozzle 19 (closed), injector driving nozzle 20 ( open), pressure spring 21 , valve cone 22 and strainer 25 .

According to the invention, when opening the compressed air supply via the bore 26, the valve cap 14 is pressed onto the lower valve part 12 of the return check valve, thereby being opened and the hammer mechanism of the rotary hammer set in motion.

At the same time, according to the invention, the compressed air flows through bores No. 26 and No. 27 into the valve chamber 28 , thereby opening the check valve of the injector propellant nozzle and escaping via the feed bores 29 compressed at high speed from the initially conical propellant nozzle bore 30 .

Claims (2)

1. deep hole hammer consisting of cylinder, percussion piston, front housing, percussion drill, control valve and hammer head with connecting piece, characterized in that in the hammer head 23 or in Ge thread nipples 18 at any point between the extension rods a determinable, from the drilling deposit and the delivery quantity the compressor-dependent, the number of injector drive nozzles 19 and 20 is arranged, the nozzle bore 30 at the upper end widening conically inwards, flow-accelerating and the underside formed with a spring chamber 31 , a compression spring 21 with valve cone 22 made of plastic materials or pla takes up the conical insert and offers the greatest possible protection against contamination. 2. deep hole hammer according to claim 1, characterized in that below the injector drive nozzles 19 and 20, a check valve is arranged either in the upper hammer part 23 or in threaded nipples 11 at an arbitrary point, the valve seat in the hammer drill or as a separately sealed ring 16 executed a self-centering Valve cap 14 with sealing ring 15 slidably receives on a valve lower part 12 with spring chamber 32 and spring 13 .