Word International VL-140
*New* Wolf VL140 Drifter
Available for the Low Price of Only
The VL-140 DRill is a 140mm bore, valveless, hammer
incorporates an independently controlled, gear type, air powered
rotation motor to rotate the drill steel in place of the conventional
rifle bar, rifle nut rotation.
The VL-140 Drill is capable of drilling 2-1/2"
(64mm) to 4" (102mm) diameter holes in all types of ground
formations. It is recommended for use on our "Crawlair"
self-propelled mountings, and for surface applications with chain feed
mountings on any type of fixed or mobile drilling rig.
The VL-140 is a valveless tool. An air
distributor, controlled by an extension on the piston head, is used in
place of conventional valve chest assembly. This is a much
simpler design, and therefore, reduces the number of parts and critical
A double blower tube construction is standard on the
VL-140. It includes a 9/16 in. (14.3mm) O.D. Plastic blower
tube within a 3/4 in. (19mm) O.D. Steel tube support. The
standard chuck parts (jaw, aligner, and retainer) accomodate a four
splined striking bar with 1-3/4" (45mm) shank and stem diameters.
The VL-140 drill is equipped with an independently
controlled, air powered gear type rotation motor. This heavy duty
3 hp motor is mounted on top of the drive gear cover at the lower end
of the drill. The rotation motor is independently controlled, and
is designed to provide continuous drill steel rotation. The
operator controls the speed and direction of rotation (conventional
forward [L.H.], Neutral [no rotation], or Reverse [R.H.] from a remote
lb. (191 kg)
in. (140 mm)
in. (92 mm)
|Size of Main
Air Inlet Hose Required
in. (38 mm)
Blower Hose Required
|Size of Air
|3 @ 90
psi (3 @ 620 kPa)
Chuck (at stall & 90 psi [620 kPa] )
lb-ft. (140 mm)
Speed at Chuck (norm. Oper. Speed)
lbs. (191 kg)
lbs. (205 kg)
ft. (0.14 cu. m.)
The total air consumption of the VL-140 consists of
three parts. They are:
This is the air required to reciprocate the
piston. It depends only on the pressure at the drill main air
This is the air passed through the drill steel to
blow the chips out of the hole. The amount consumed depends on
the pressure at the blow inlet in the backhead and the number of the
steels in the string. In some instances, when drilling in hard
uniform rock, the operator uses more blow air then necessary. In
such cases, improved drill performances can be obtained by throttling
back the blow air to divert additional air to the hammer, so that the
drill runs at higher pressure.
This is the air requried to rotate the drill steel
and bit. The operator can control the power and air consumption
of the rotation motor by controlling the pressure supplied to the
motor. If he runs the rotation wide open, the motor will run at
maximum speed and air consumption. If he throttles back on the
pressure to the motor, it will run slower and consume less air.
The air conserved by throttling back the rotation air pressure will be
diverted to the drill hammer and will improve drilling performance by
increasing the operating air pressure. The total amount of air
used is, therefore, dependent upon several factors. However, the
following can be expected when using a 600 cfm (17 cu/m min)
compressor in good condition at sea level.
- 82 PSI at the drill inlet when running continuous rotation wide
open as in overburden drilling.
- 90 PSI at the drill inlet when running continuous rotation
throttled back as in average rock formations.
A 750 cfm (21.2 m3
compressor must be used to maintain an air pressure of 100 PSI or more
at the drill inlet, and in addition, provide the required volume of air
for blow and rotation.
The air pressures indicated in
above paragraphs are based on readings
taken at sea level. The pressures will be 2.5 PSI (17 kPa)
every 1000 ft (304m) altitude above sea level.
An air compressor having a capacity for 750
cfm (21.2 m3
/min) is required to provide the necessary
volume of air at the most efficient pressure for the VL-140 drill.
Pressure and Volume
Low or inadequate air pressure at the drill is
costly and wasteful.. In addition, an insufficient volume of air at the
drill will not allow the machine to operate in the most officient
An air pressure of 100 PSI is recommended for
maximum performance of the VL-140 drill. This figure represents
the air pressure at the drill and not at the compressor. There is
always a certain amount of line drop between the compressor and the
drill, and only the pressure and volume at the drill can be effective
in doing work. If hoses are short and in relatively good
condition, pressure drop between the compressor (or air receiver) and
point of use should not exceed 15 percent of the initial pressure.
Air Hose and Fittings
Quality hose designed especially for rock drill
service should be used. It should be constructed with an outer
covering which resists abrasive wear; it should have an oil resistant
inner tube; and must be designed to withstand the heat of the
compressor's air. The hose should be at least one size larger
than the pipe thread on the drill. It should have a working
pressure safety factor of at least 4-to-1 in relation to burst.
The hose fitting should be kept as tight as possible
and should be in good condition. Elimination of air leakage
involves making the air system tight and then keeping it tight.
Air losses, through bad connections and worn hose, can often reach
10-20% of the total air compressed.
The backhead is a compact steel unit with threaded
inlet ports for the blower tube retainer and main air inlet
connection. The inlet connection is forged steel (90°) with
screwed-in straight hose stem for a 1-1/2 in. (38 mm) main air
hose. It is attached to the backhead by a cap and retaining ring
so that it is free to swivel in the backhead.
The VL-140 is a valveless drill: a simple air
distributor (no moving parts) is installed in the rear bore of the
cylinder in place of the valve chest assembly used in conventional
drills. The internal bore of the air distributor is fitted with a
pressed-in replaceable bronze liner which relieves the distributor body
of wear. Ports in the air distributor body (and liner) direct the
main operating air through the front and rear piston supply
ports. The intermitent flow of air through the front and rear
main air supply ports is controlled by a piston extension that extends
into the distributor body, and opens and closes the air supply ports as
the piston reciprocates. A long key is installed along the O.D.
of the distributor body to align the ports in the distributor with the
connecting ports in the cylinder.
The piston is designed with an integral piston
extension that projects from the rear end of the piston head. It
extends into the bore of the air distributor when the drill is
assembled, and, as the piston reciprocates, opens and closes the main
air supply ports to the front and rear ends of the piston.
The piston bearing is designed with long bearing
surfaces and with two pressed-in sleeves; one to take wear from the
piston stem and one to take wear from the chuck. The chuck is
supported in both the fronthead and the counter bore in the piston stem
bearing. Gear teeth on the O.D. of the chuck mesh with chuck
drive intermediate the gear to rotate the chuck smoothly. The
chuck engages the chuck jaw to transmit rotation to the shank piece.
The rear end of the fronthead is counterbored to
support the chuck drive intermediate gear shaft and the piston end of
the motor drive gear. The front end of the fronthead is equipped
with a replaceable bronze fronthead bushing that takes all wear and
prolongs the service life of the chuck and fronthead.
The VL-140 is designed with an air powered, integral
rotation motor which includes a motor drive gear, and an enclosed
housing assembly consisting of an air motor manifold and a motor gear
housing. The motor drive gear and idler gear convert the
operating air to rotation power. The rotation power developed by
the drive gear is transmitted through a drive gear shaft, which extends
through the center bore of the drive gear, to the chuck drive
intermediate gear. The intermediate gear meshes with the chuck
gear to transmit the motor rotation to the drill steel.
The motor manifold encloses the rear end of the
rotation motor, and includes two inlet ports for the forward and
reverse control hoses. The forward rotation port includes a
metering plug to cut down the rotation motor air consumption, and
therefore, allow a greater volume of air to be directed to the drill
hammer to improve drilling performance.
This product was added to our catalog on Tuesday 14 August, 2012.