Bulroc ODS 90

Eccentric Overburden Drilling System

Drilled Hole Diameter 4.88" -- Casing Size 4.5" O.D. x 3.96" I.D.

The ODS 90 is a two-part Eccentric Overburden Drilling System designed for the simultaneous installation of casings to support unstable ground conditions. The bit holder is fitted into the hammer in the same way as a conventional button bit would be. The Eccentric Button Bit is locked into the Bit Holder by means of a double "Seloc" pin arrangement that can be removed when the Bit needs either regrinding or replacing. Bulroc only supplies threaded Casings, but the system can also be used with less expensive Welded Casings when the Casing is required to be left in the hole.

When the ODS 90 has been drilled to the required depth, the Eccentric Bit can be closed to its concentric position and the complete system withdrawn from the Casing. If required, it is then possible to drill on into solid rock using a Conventional Button Bit with a maximum diameter of 3.54". It is important to make sure that a stabilizer of the correct dimensions is positioned directly behind the hammer. On deep angled holes it is recommended that further stabilizers are positioned after 32.81 feet of drill tube.

Complete System: Hyper 31, Mach 33, and DHD3.5 (COP32 by special order).
A complete system comprises Bit Holder, Eccentric Bit, and Locking Pin.

Technical Specifications

		Component Parts
		Reference	Description
		1	Bit Holder Hyper 31
			Bit Holder Mach 33
			Bit Holder DHD3.5
		2	Locking Pin Set
		3	Eccentric Bit
		4	Casing Shoe
		5	Starter Casing, Pin Up (complete with shoe)
		6	Stabilizer
		Specifications
		Bit Holder O.D.	3.94"
		System Closed	3.6"
		System Open	4.88"
		Casing Size	4.5" O.D. x 3.96" I.D.
		Total Weight (bit and bit holder)	35.2 lbs.