Drill Rods and Extension Equipments

Integral Drill Steel Series

Integral Drill Steels are normally produced from 19mm (3/4" ), 22mm ( 7/8") or 25mm (1") Hexagon Drill Steel, where the dimensions given are measured across the flat of the hexagon.

Integral Drill Steels are a fixed length with a shank at one end and a bit at the other, and are able to drill to a depth equivalent to their effective length. The bit may consist of a single chisel shaped tungsten carbide insert or three such inserts.

To drill deep holes, the rods are designed to be used in a series where the length of any rod used is longer than the one used just before it. To do this, a series of rods must be produced so that the bit diameter is reduced for each increase in length of rod to prevent jamming of the bit in the hole.

The table shown below indicates some of the most common series of Integral Drill Steels produced :-

7/8" Drill Steels

Series 1
Effective Length (mm)	Bit Dia (mm)	Order Code
800	34	834
1600	33	1633
2400	32	2432
3200	31	3231
4000	30	4030
4800	29	4829
5600	28	5628
6400	27	6427

Series 2
Effective Length (mm)	Bit Dia (mm)	Order Code
800	40	840
1600	39	1639
2400	38	2438
3200	37	3237
4000	36	4036
4800	35	4835
5600	34	5634
6400	33	6433

Series 3
Effective Length (mm)	Bit Dia (mm)	Order Code
400	34	434
800	33	833
1200	32	1232
1600	31	1631
2000	30	2030

Series 4
Effective Length (mm)	Bit Dia (mm)	Order Code
600	35	635
1200	34	1234
1800	33	1833
2400	32	2432

Series 5
Effective Length (mm)	Bit Dia (mm)	Order Code
600	41	641
1200	40	1240
1800	39	1839
2400	38	2438

Series 6
Effective Length (mm)	Bit Dia (mm)	Order Code
800	36	836
1600	35	1635
2400	34	2439
3200	33	3233
4000	32	4032