General Description
The YD90 Drifter is a 90 mm ( 3 ½ in ) bore hammer driller that 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 YD90 is capable of drilling 44 mm ( 1 ¾ in ) to 64 mm ( 2 ½ in ) diameter holes in all types of ground formations. It is recommended for the LM100A Crawlair Mountings.

The YD90 Drifter is design with a 13.0 mm ( ½ in ) OD and 11 mm ( 7/16 in ) ID Blower Tube swaged down to 10.2 mm ( 13/32 in ) OD and 8.2 mm ( 21/64 in ) ID. The standard chuck parts ( jaw, bushing, and cap ) accommodate a four splined shank piece with 38 mm ( 1 ½ in ) shank and stem diameters. THe YD90 Drill is equipped with an independently controlled, air powered gear type rotation motor. This heavy duty 1.04 kW ( 1.4 hp ) motor is mounted on top of the chuck end. 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 control valve.

Specifications
Drifter Specifications

	Metric	U.S.
Weight of Drifter	85 kg	187 lbs.
Overall Length	780 mm	30 11/16 in.
Bore of Cylinder	90 mm	3 5/16 in.
Working Stroke	85 mm	3 1/3 in.
Size of Main Air Inlet Hose Required	25 mm	1 in.
Size of Blower Hose Required	19 mm	¾ in.

Drifter Rotation Motor Specifications

	Metric	U.S.
Size of Air Hoses Required ( 2 )	19 mm	¾ in.
Brake Kilowatt ( Horsepower )	1.04 at 621 kPa	1.4 at 90 psi
Torque at Chuck ( at 100 rpm )	29 N° m at 621 kPa	21 lb / ft at 90 psi
Rotation Speed at Chuck	200 - 300 rpm	200 - 300 rpm
Maximum Chuck Rotation Speed	380 rpm	380 rpm

Steel ( Coupled Type )

Steel Size → 32 mm ( 1 ¼ in. ) Hollow Round

Thread Type → 32 mm ( 1 ¼ in. ) SPI-RAL

Drifter Shipping Information

	Metric	U.S.
Net Weight	85 kg	197 lbs.
Shipping Weight	92 kg	203 lbs.
Cu Contents ( Boxed )	.20 m³	7 ft³

Air Consumption

The total air consumption of the YD90 consists of three parts.
These are:

1. Drill - This is the air required to reciprocate the piston. It depends only on the pressure at the drill main air inlet.
    
2. Blow - 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 steels in the string. In some instances, when drilling in hard uniform rock, the operator uses more blow air than necessary. In such cases, improved drill performance can be obtained by throttling back the blow air to divert additional air to the hammer, so that the drill runs at a higher pressure.
    
3. This is the air required 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 maximum 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 improved drilling performance by increasing the operating air pressure.

The total amount of air used, therefore, is dependent upon several factors. However, the following can be expected when using a 365 cfm ( 10.3 m³ / min ) compressor in good condition at sea level.

1. 565 kPa ( 82 psi ) at the drill inlet with the rotation wide open.
    
2. 621 kPa ( 90 psi ) at the drill inlet with the rotation throttled back.

Note
These readings are based on reading taken at sea level. For every 305 m ( 1,000 ft ) above sea level, the pressures will be 17.2 kPa ( 2.5 psi ) lower.

---

→ Click Here ←
To Return To The Used Drifter Drills Page