G E S C O G R O U P "Hole Openers"

Sheet 1

SEALED BEARING - SH - SERIES

Tool Features:
The Darron single slage hole opener is a simple but rugged design. The body is machined from AISI 4145 fully heat treated alloy steel with arms welded onto the body providing location for the cutters. Arms and cutters are hardfaced for protection, the cutters are available in 3 different designs for varying conditions and rock formations (see sheet la for more details The cutter assembly is a fully sealed unit incorporating ball and roller bearings Retaining the whole assembly is achieved by a locking pin. The design of the hole opener enables quick overhauls on the rig site. 3 or 6 replaceable nozzles are used giving optimum mud circulation around the cutters.

When enquiring or ordering please specify:
1) Hole size
2) Pilot size
3) Connection types
4) Cutter type (see sheet la)

BODY	HOLE	PILOT	A	B	C	D		TOP PIN	BTMBOX	ASS
WRTNO.	SIZE	SIZE	LENGTH	FN LENGTH	FISHING DIA	TONG DIA		CONN.		IWEIGHT Kgsl

SOS	8½"	5⅞"	64"	24"	6½"	4½"	1¼"	4½" lF	3 ½" REG	230
SO9	9⅝"	6½"	66"	24"	6½"	4½"	1¼"	4½" lF	3ft" REG	240
S12	12¼"	8½"	70"	28"	8"	6"	1½"	6⅝" REG	4ft" REG	410
SI5	14¾"	9⅝"	70"	28"	8"	7½"	1½"	6⅝" REG	6 ⅝" REG	460
S16	16"	12¼"	72"	28"	9½"	8"	2¼"	7⅝" REG	6 ⅝" REG	600
S17	17½"	12¼"	74"	28"	9½"	8"	2¼"	7⅝" REG	6 ⅝" REG	625
S24	24"	17½"	80"	30"	9½"	9ft"	2¼"	7⅝" REG	7 ⅝" REG	965
526	26"	17½"	82"	30"	9½"	9½"	3"	7 ⅝" REG	7 ⅝" REG	1010
536	36"	26"	84"	30"	9½"	9½"	3"	7 ⅝" REG	7 ⅝" REG	1360

Special requirements can be accommodated on request

Sheet 1a

SEALED BEARING - SH - SERIES

Cutter Features:
Generally the cutter assembly consists of 4 machined parts:- cutter, inner bearing race, spindle and locking key - roller and ball bearings and seals completing the assembly. All machined parts are fully surface hardened. A choice of cutler types are shown below.

Cutter type ST - soft to medium formations
- Open design tooth formation
- Tooth surfaces hardfaced

Cutter type MM - medium to hard formations
- Closed design tooth formation
- Tooth surfaces hardfaced

Cutter type HD - extra hard formations
- Button type design (spherical TCI)

BODY PART No.

HOLE SIZE

PILOT SIZE

* CUTTER PART No.

* Prefix cutter part number with relevant cutter Type:- ST
MM
HD

SOS

8½"

5⅞"

S09

9⅝"

6½"

S12

12¼"

8ft"

123

S15

14¾"

9⅝"

151

S16

16"

12¼"

162

S17

17½"

12¼"

172

S24

24"

17½"

243

S26

26"

17½"

263

S36

36"

26"

361

Sheet 1

INTEGRAL BODY-SEALED BEARING-S.H.I.SERIES

Tool Features:

Designed for the enlargement of pilot holes, directional drilling and large hole applications, the Darron S.H.I, series hole openers are manufactured from chromium molybdenum solid alloy steel forgings. heat treated and conforming to the requirements of AIS.I.4145 H modified

· By design the fully integral construction of the body eliminates any requirement for welding on the body and cutter arms

· The body and cutter arms are hardfaced for protection and cutters are available from our 3 standard designs, S.T, M.M. and H.D. all of which are fully interchangeable.

· Non standard cutters can also be supplied to meet specific applications

· The cutter assembly is a fully sealed unit incorporating ball and roller bearings providing optimum performance.

· Cutter assemblies can be easily changed out at the rig site using readily available hand tools.

· Circulation is achieved by either a 3 or 6 nozzle configuration on the body (3 in the cutter pockets and 3 in the wing areas!. This is dependent on the hole opener body size.

· The body can be provided with a fully integral bullnose complete with reverse circulation facilities or with a rock bit connection with optional separate bullnose.

When enquiring or ordering please specify:-

1) Hole size.

2) Pilot size.

3) Connection size and type.

4) Cutter type (see sheet 1 A).

5) Circulation nozzle size and type.

6) Pilot type (Rock bit/Bullnose/Integral Bullnose).

7) If Bullnose type is selected please specify type required

i.e. Plain, Side Hill or Spiral and any special circulation requirements.

Note: please state part no. from table below where possible.

HOLE SIZE

PILOT SIZE

F/N LENGTH

FISHING NECK DIA

TONE NECK DIA

INSIDE DIA

TOP PIN CONN.

BIT BOX CONN.

PART No.

INTEGAL BULLNOSE-PART Nos

PLAIN

SIDE HILL

SPIRAL

8½"

5⅞"

30"

6½

4½

4½" IF

3½" REG

I 08

I 08-A

I 08-B

I 08-C

12¼"

8½"

30"

6⅝" REG

4½" REG

I 12

I 12-A

I 12-B

I 12-C

16"

12¼"

36"

9½

2¼"

7⅝" REG

6⅝" REG

I 16

I 16-A

I 16-B

I 16-C

17½"

12¼"

36"

9½

2¼"

7⅝" REG

6⅝" REG

I 17

I 17-A

I 17-B

I 17-C

22"

15½"

42"

9½

2¼"

7⅝" REG

I 22

I 22-A

I 22-B

I 22-C

24"

17½"

42"

9½

2¼"

7⅝" REG

I 24

I 24-A

I 24-B

I 24-C

26"

17½"

42"

9½

7⅝" REG

I 26

I 26-A

I 26-B

I 26-C

NOTE

1. Standard circulation placement comprises of one central downward facing jet and three reverse circulation jets.

2. A separate bullnose for the three types shown can be supplied.

3. Special requirements can be accommodated on request

Sheet 1a

INTEGRAL BODY-SEALED BEARING-S.H.I.SERIES

Cutter Features:

Generally the cutter assembly consists of 4 machined parts-cutter, inner bearing race, spindle and locking key - roller and ball bearings and seals completing the assembly. All machined parts are fully surface hardened, A choice of cutter types are shown below.

ST	MM	HD



FOR SOFT TO MEDIUM FORMATIONS • OPEN DESIGN TOOTH FORMATION • TOOTH SURFACES HARDFACED	FOR MEDIUM TO HARD FORMATIONS • CLOSED DESIGN TOOTH FORMATION • TOOTH SURFACES HARDFACED	FOR EXTRA HARD FORMATIONS • BUTTON TYPE DESIGN (SPHERICAL T.C.I.)

BODY PART No.	HOLE SIZE	PILOT SIZE	CUTTER TYPE PART Nos.

			ST	MM	HD

I 08	8 ½"	5 7/8"	ST 82	MM 82	HD 82
I 12	12 ¼"	8 ½"	ST 123	MM 123	HD 123
I 16	16"	12 ¼"	ST 162	MM 162	HD 162
I 17	17 ½"	12 ¼"	ET 172	MM 172	HD 172
I 22	22 "	15 ½"	ST 243	MM 243	HD 243
I 24	24 "	17 ½"	ST 243	MM 243	HD 243
I 26	26 "	17 ½"	ST 263	MM 263	HD 263

Non standard cutters can also be supplied to meet specific application