Vertical Borer Stabilizer Rod Bushes
This
is a standard application used by a borer company and is machined from Vesconite
bushing with an outside diameter 300 x 250 - 1000 mm (11.8" x 10" - 39.4") standard stock. The boring
machine is used to bore out chutes from one level to the other. This particular
machine bores a 1½ metre hole at angles varying from the vertical to a 30o
incline. Chutes up to 120 m long can be bored.
The
hole is drilled at a rate of 1.5 metres (5') per hour. All the rock, chips and debris
that result form the cutting action fall down the hole along the length of the
drill steels and contaminate the bearing surfaces.
Stabilizers to align the drill steel and prevent whip are placed every 5 metres (16') along the length of the drill pipe. Each stabiliser is lined with a Vesconite bush. The drill rotates at 16 rpm within the Vesconite bushing. Spring loaded lip seals are used to provide some protection from rock chips, abrasive debris and run of mine water.
There are 20 stabilizer rods per machine, each rod being approximately 1 m (3.3') long. On the upward drill every fifth rod is a stabilizer rod. The use of Vesconite allowed greasing to be reduced to overhauls only. Vesconite has a 12 - 15 month life in this application. No other material worked successfully in this application.
Updated Apr 26 2002
