Drilling System
Adjusting High Percussion Pressure
NOTE
Factory setting is 150 bar (2176 psi).
NOTE
For drill rod < 32 mm (1.26 inches), percussion pressure above 150 bar (2176 psi) is not recommended.
Precondition
The hydraulic oil is at operating temperature 40 °C (104°F).
- 1.Make sure that the switch on the drilling lever is in position high percussion pressure. Quick setting of high percussion pressure is activated with button
on the operator panel.
- 2.Raise and lower the pressure using button
and
respectively.
- 3.Read the percussion pressure on pressure gauge (A).
Low Percussion Pressure Adjustments
NOTE
The factory setting is 120 bar (1740 psi) and is not adjustable.
Recommended Pressure
Recommended pressures for the drill rods with diameter ≤ 41 mm (1.6 in.)
Pressure/Flow Setting | Parameter Unit / Rock Condition (m/min) | ||
|---|---|---|---|
Hard / 0.2–1.5 | Medium / 1.5–2.5 | Soft / >2.5 | |
High impact pressure | 160–170 bar (2320.6–2465.6 psi) | 150–160 bar (2175.5–2320.6 psi) | 140–150 bar (2030.5–2175.5 psi) |
Low impact pressure | 120 bar (1740.4 psi) | 120 bar (1740.4 psi) | 120 bar (1740.4 psi) |
High feed pressure | 110–120 bar (1535.4–1740.4 psi) | 100–110 bar (1450.3–1535.4) | 90–100 bar (1305.3–1450.3) |
Low feed pressure | 50 bar (725.1 psi) | 50 bar (725.1 psi) | 50 bar (725.1 psi) |
Recommended pressures for the drill rods with diameter > 41 mm (1.6 in.)
Pressure/Flow Setting | Parameter Unit / Rock Condition (m/min) | ||
|---|---|---|---|
Hard / 0.2–1.5 | Medium / 1.5–2.5 | Soft / >2.5 | |
High impact pressure | 150–160 bar (2175.5–2320.6 psi) | 140–150 bar (2030.5–2175.5 psi) | 130–140 bar (1885.4–2030.5 psi) |
Low impact pressure | 120 bar (1740.4 psi) | 120 bar (1740.4 psi) | 120 bar (1740.4 psi) |
High feed pressure | 105–115 bar (1522.8–1667.9 psi) | 95–105 bar (1377.8–1522.8 psi) | 85–95 bar (1232.8–1377.8) |
Low feed pressure | 50 bar (725.1 psi) | 50 bar (725.1 psi) | 50 bar (725.1 psi) |
Adjust High Drill Feed Pressure
Factory setting is 100 bar (1450 psi).
Precondition
The hydraulic oil is at operating temperature 40 °C (104 °F).
- 1.Activate the functions for collaring.
- 2.Make sure the flushing air is on.
- 3.Activate high percussion.
- 4.Go to manual drill feed.
- 5.Press the rapid feed button
on the operator panel. Press arrow up
- 6.Press arrow down
- 7.The drill feed pressure can be read on the pressure gauge for the drill feed pressure (A).
Pressure Regulator Adjustment
A | Compressor pressure gauge |
B | Regulator wheel with automatic locking |
Setting the compressor maximum temperature and operating pressure.
Compressor Operating Pressure | |
|---|---|
Maximum pressure | Maximum temperature |
8.5 bar | 120 ºC |
Rotation Speed Adjustment
NOTE
Rotation speed can be set without drilling taking place.
The hydraulic oil should be at operating temperature, normally 40 °C (104°F). To measure rotation speed, count the number of revolutions the drill string completes per minute (make a mark on the drill rod). Correct rotation speed should be set according to the type of drill bit and the properties of the rock.
Observe the following guidelines:
Size of drill bit
Small drill bits demand a higher rotation speed than large drill bits.
Size of drill bit (mm) | 33 | 35 | 38 | 41 | 45 |
Rotation speed (rpm) | 170 – 220 | 170 – 220 | 150 - 220 | 150 – 220 | 130 – 170 |
Type of drill bit
X drill bits (cross drill bits) require a higher speed than button drill bits (10–20 rpm higher)
Rock properties
Soft types of rock normally require a higher speed, harder rock requires a lower rotation speed.
Jerky rotation
if rotation speed is jerky during drilling (not rotating at even speed). This could indicate that rotation speed is too low.
In certain types of rock, ballistic drill bits can cause jerky rotation.
Drill bit wear
Diametric wear can be reduced if rotation speed is lowered
Penetration rate
High rotation speed can give a higher drilling rate.
Ballistic button drill bits normally give a higher drilling rate.
X drill bits give lower drilling rates.
NOTE
In the case of heavy wear on drill bit diameter (skirt), reduced flushing air must be used.
Setting Rotation Speed
- 1.Press the rotation button
on the operator panel to activate rotation speed.
- 2.Raise and lower the rotation speed using button
Anti-Jamming Protection
The drill rig is equipped with an anti-jamming device. The rotation pressure switch reduces feed, percussion pressure in the event of increased rotation pressure.
The reduction of feed, percussion pressure is started at 50-bar (725 psi) rotation pressure.
At 70-bar (1015 psi) rotation pressure feed pressure becomes 0, that is, the rock drill is stationary.