- 85 664 75 34
- handel@darmet.com.pl
- Darmet sp. z o.o.
Zakład Obróbki Skrawaniem
ul. Komunalna 4c, 15-197 Białystok
Our adress:
Darmet sp. z o.o.
Zakład Obróbki Skrawaniem
Komunalna 4c street, 15-197 Białystok
Our e-mail:
handel@darmet.com.pl
Telephone number:
+48 85 664 75 34
Deep Hole Drilling Guidelines - Structural Steel T-A®
Step 1: Pilot Hole
- 100% RPM
- 100% IPR (mm/rev)
Details:
- Establish the pilot hole using the same diameter short drill to a depth of 2xD minimum.
- Utilize a pilot drill with the same or larger included point angle.
Coolant: ON
![DHD TA Coolant ON](/images/stories/amec/original/DHD_TA_Coolant_ON.png)
![DHD SS TA 1](/images/stories/amec/ss/DHD_SS_TA_1.png)
![Icon Warning](/images/stories/amec/gen3sysXT/Icon-Warning.png)
- 50 RPM max
- 12 IPM (300 mm/min)
Details:
- Feed the longer drill within 1/16" (1.5mm) short of the established pilot hole bottom at a maximum of 50 RPM and 12 IPM (300 mm/min) feed rate.
Coolant: OFF
![DHD TA Coolant OFF](/images/stories/amec/original/DHD_TA_Coolant_OFF.png)
![DHD SS TA 2](/images/stories/amec/ss/DHD_SS_TA_2.png)
Step 3: Deep Hole Transition Drilling
- 50% RPM
- 75% IPR (mm/rev)
Details:
- Drill additional 1xD past the bottom of the pilot hole at 50% reduction of recommended speed and 25% reduction of recommended feed.
- Minimum of 1 second dwell is required to meet full speed before feeding
Coolant: ON
![DHD TA Coolant ON](/images/stories/amec/original/DHD_TA_Coolant_ON.png)
![DHD SS TA 3](/images/stories/amec/ss/DHD_SS_TA_3.png)
Step 4: Deep Hole Drilling - Blind
- 100% RPM
- 100% IPR (mm/rev)
Details:
- Drill to full depth at recommended speed and feed for longer drill according to Allied speed and feed charts.
- No peck cycle recommended.
Coolant: ON
![DHD TA Coolant ON](/images/stories/amec/original/DHD_TA_Coolant_ON.png)
![DHD SS TA 4](/images/stories/amec/ss/DHD_SS_TA_4.png)
Step 5: Deep Hole Drilling at Breakout
- 50% RPM
- 75% IPR (mm/rev)
Details:
For through holes only:
- Reduce speed by 50% and feed by 25% prior to breakout.
- Do not break out more than 1/8" (3mm) past the full diameter of the drill.
Coolant: ON
![DHD TA Coolant ON](/images/stories/amec/original/DHD_TA_Coolant_ON.png)
![DHD SS TA 5](/images/stories/amec/ss/DHD_SS_TA_5.png)
![Icon Warning](/images/stories/amec/gen3sysXT/Icon-Warning.png)
- 50 RPM max
Details:
- Reduce speed to a maximum of 50 RPM before retracting from the hole.
Coolant: OFF
![DHD TA Coolant OFF](/images/stories/amec/original/DHD_TA_Coolant_OFF.png)
![DHD SS TA 6](/images/stories/amec/ss/DHD_SS_TA_6.png)
![Icon Warning](/images/stories/amec/gen3sysXT/Icon-Warning.png)
- When using holders without support bushing, use a short T-A® holder to establish an initial hole that is a minimum of 2 diameters deep.
- Do not rotate tool holders more than 50 RPM unless it is engaged with the workpiece or fixture.