GB2117428A

GB2117428A - Improvements in or relating to rotary percussion core hammers

Info

Publication number: GB2117428A
Application number: GB08234155A
Authority: GB
Inventors: Melvyn Samuel James Ennis
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-02-11
Filing date: 1982-11-30
Publication date: 1983-10-12
Also published as: GB2117428B

Abstract

The invention relates to an improved particle sampling air hammer drill and which contains a by- pass tube 14 and flushing device 15 which allows high pressure compressed air to directly flush a central sample tube 5 continuously and independently of the lower pressure air exhausted from the hammer mechanism 1, which itself flushes out directly through the drill bit to the cutting face, which contains an eccentric cutting tooth 16 which disintegrates any core sample into particulate material. <IMAGE>

Description

SPECIFICATION Improvements in or relating to rotary percussion core hammers This invention relates to a method and apparatus for drilling and sampling any ground strata or formation of overburden or bedrock or man-made structures and is for use with any drilling machine capable of bore hole drilling in vertical, horizontal or angular boring.

The method and apparatus provides a continuous uncontaminated sample of whatever drilled and may be employed for any application requiring the drilling or boring of a hole under any climatic conditions throughout the world either onshore or offshore and in or on inland waters.

Sample recovery may be in the form of sludge, particles or chip cuttings.

An embodiment of the invention is to be found in Figs. 1 and 2 where the apparatus consists of a down-hole rotary percussion hammer (1) attached to dual wall drill rods or tubes (2) employing reverse circulation flushing technique.

Attached to the cutting end of the hammer are steel or tungsten tipped or similar drill bits in the form of blade, button or similar cutting faces (3).

The method consists of high pressure air moving down the annual area within the dual wall drill tubes (2) into the down-the-hole rotary percussion core hammer (1). This activates a hollow piston (7) which strikes the hollow drill bit (3). The rapid up and down motion of piston (7) is controlled via a flap valve system (8) which directs compressed air alternatively into chambers (9) and (10). A combined percussion and/or rotation motion is set in operation and the chip cuttings, particles, or whatever is being drilled are transported upwards via the sample tube (5) to the surface by compressed air. Drill bit (3) is held in position in the hammer cylinder 1) via a screw in chuck (12) and several torque plugs (13).

The method does not require the need for the drill hole to be cased or lined as drilling proceeds but yet will provide continuous sampling of the hole, the sample itself being uncontaminated from material already drilled. The only limits on the size or depth of hole drilled are those dependent on the drill rig capabilities itself.

The method and apparatus described above represents a system of drilling ideally suitable for obtaining disturbed but uncontaminated samples.

If differs from all existing drilling systems in many features but principally when compared with all existing rotary percussion hammers it incorporates a unique bye-pass tube (14) which directs flushing air past the hammers mechanism to a U-tube device (15) which then directs the compressed air at a high upward angle into the .central core tube (5). The U-tube device (15) may be altered to also direct all of the hammers exhaust air into the central core tube (5) or none of it, in which case the exhaust air is ported out through the drill bit (3). Large volumes of compressed air may thus be channeled into the central core tube (5) to allow sufficient lift velocity to carry cuttings to the surface on a continuous basis as drilling proceeds.The drill bit (3) is also of unique design in that there exists an eccentric cutting tooth (16) located in the central hole which breaks up large rock pieces and so prohibits solid cores to form, thus allowing chip sizes to pass into the central core tube (5), see Fig. 2.

Claims (Filed on 10-2-83) 1. Apparatus for continuously taking chip and particle samples while drilling a bore hole, having an air powered hammer device with an annular hammer piston striking an annular drill bit containing a central eccentric cutting tooth to provide breakage of the sample, and the hammer device containing a flushing tube which by-passes hammer mechanism to allow high pressure air to flush directly and continuously at high upward angle into sample tube independent of hammer mechanisms exhaust air which flushes directly out through drill bit at lower pressure.

2. A sampling hammer drill substantially as herein before described with reference to, and as shown in, the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in or relating to rotary percussion core hammers This invention relates to a method and apparatus for drilling and sampling any ground strata or formation of overburden or bedrock or man-made structures and is for use with any drilling machine capable of bore hole drilling in vertical, horizontal or angular boring. The method and apparatus provides a continuous uncontaminated sample of whatever drilled and may be employed for any application requiring the drilling or boring of a hole under any climatic conditions throughout the world either onshore or offshore and in or on inland waters. Sample recovery may be in the form of sludge, particles or chip cuttings. An embodiment of the invention is to be found in Figs. 1 and 2 where the apparatus consists of a down-hole rotary percussion hammer (1) attached to dual wall drill rods or tubes (2) employing reverse circulation flushing technique. Attached to the cutting end of the hammer are steel or tungsten tipped or similar drill bits in the form of blade, button or similar cutting faces (3). The method consists of high pressure air moving down the annual area within the dual wall drill tubes (2) into the down-the-hole rotary percussion core hammer (1). This activates a hollow piston (7) which strikes the hollow drill bit (3). The rapid up and down motion of piston (7) is controlled via a flap valve system (8) which directs compressed air alternatively into chambers (9) and (10). A combined percussion and/or rotation motion is set in operation and the chip cuttings, particles, or whatever is being drilled are transported upwards via the sample tube (5) to the surface by compressed air. Drill bit (3) is held in position in the hammer cylinder 1) via a screw in chuck (12) and several torque plugs (13). The method does not require the need for the drill hole to be cased or lined as drilling proceeds but yet will provide continuous sampling of the hole, the sample itself being uncontaminated from material already drilled. The only limits on the size or depth of hole drilled are those dependent on the drill rig capabilities itself. The method and apparatus described above represents a system of drilling ideally suitable for obtaining disturbed but uncontaminated samples. If differs from all existing drilling systems in many features but principally when compared with all existing rotary percussion hammers it incorporates a unique bye-pass tube (14) which directs flushing air past the hammers mechanism to a U-tube device (15) which then directs the compressed air at a high upward angle into the .central core tube (5). The U-tube device (15) may be altered to also direct all of the hammers exhaust air into the central core tube (5) or none of it, in which case the exhaust air is ported out through the drill bit (3). Large volumes of compressed air may thus be channeled into the central core tube (5) to allow sufficient lift velocity to carry cuttings to the surface on a continuous basis as drilling proceeds.The drill bit (3) is also of unique design in that there exists an eccentric cutting tooth (16) located in the central hole which breaks up large rock pieces and so prohibits solid cores to form, thus allowing chip sizes to pass into the central core tube (5), see Fig. 2. Claims (Filed on 10-2-83)

1. Apparatus for continuously taking chip and particle samples while drilling a bore hole, having an air powered hammer device with an annular hammer piston striking an annular drill bit containing a central eccentric cutting tooth to provide breakage of the sample, and the hammer device containing a flushing tube which by-passes hammer mechanism to allow high pressure air to flush directly and continuously at high upward angle into sample tube independent of hammer mechanisms exhaust air which flushes directly out through drill bit at lower pressure.