Hearn SDT7 Portable Drills

The Hearn SDT7 Portable Drill has the capability to be mounted directly to a steel beam in the shop, in the yard or in the field.  The machine frame allows for a set up to drill on both flanges and webs.  A single machine operator will be able to accomplish a previously physically punishing manual drilling job requiring multiple workers in a much shorter time and with greater control and precision.


MACHINE FEATURES & CAPABILITIES

Machine Versatility

SDT7-Series Machines allows drilling capabilities in not only vertical and horizontal positioning but also inverted positioning and out of position drilling  on tub girder type beams.  Current designs come in travel area widths of 3', 4' & 6' on the Cross Feed (Y-Axis) and 6', 8', 10' & 12' lengths on the Longitudinal (X-Axis). 

Heavy Duty Frames

The SDT7-Series Machines are designed with a rugged, sturdy Frame.  Weldments with multiple lifting and securing locations & angle support rails greatly enhance versatility and ease of positioning/handling.  The machine can be moved from a vertical drilling set up to a horizontal position in just a few minutes. 


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Hearn Machine

The Global Leader in Portable Heavy Duty Steel Drills
Operational Efficiency

The use of a SDT7-Series Machine allow the user to significantly reduce the workforce currently drilling with handheld, manual machines.  A single trained operator can run the machine and drill the same number of holes it would previously have required multiple men to manually drill.  The automatic cycling power feed permits the spindle to rapidly traverse downward to a predetermined point at which it automatically slows to appropriate feedrate set by the operator.  When the drill cycle is completed, the spindle automatically rapid feeds back to its starting point, ready to move to the next hole position.   

Service Support

Hearn Machine Tool keeps a full inventory of spare parts to ensure a ready supply whenever a part is needed.  This approach allows our customers to minimize the amount of spare parts inventory they must carry and ensures that emergency downtime is minimized.



SPECIFICATIONS

The following is a summary of the standard machine specifications for the Hearn SDT7 (Portable)-Series Manual Positioning Coordinate Drilling and Light Milling Machine:

Spindle Drive Motor                                         7.5 HP (AC)
Spindle Quill Housing Diameter                      4 Inches
Spindle Quill Travel                                         7" (Standard), 11" (Extended, Optional)
Spindle Feed Rate [Infinitely Variable]            1.8 - 9.9 Inches Per Minute
Spindle Rapid Traversing Rate                       30 Inches Per Minute
Spindle Diameter                                            2 Inches
Spindle Taper (Drilling)                                   No. 4 Morse Taper Spindle
Spindle Extensions (4MT to 3MT)                  3", 6", 9", and 12"
Spindle Speeds (8 Settings)                          75, 150, 225, 300, 455, 600, 912, & 1200 RPM


The Hearn SDT7 Portable series machine is a 3 axis machine with the following axis specifications:

  • Spindle Quill Feed (Z-Axis) consists of a Rack & Pinion which is Power Fed through an 80:1 Gear Box (Standard) which can be optimized to 60:1.
  • Longitudinal Travel (X-Axis) consists also of Rack & Pinion which is Power Fed through a 60:1 Gear Box which can be optimized to either 80:1. 
  • Cross Feed (Y-Axis) consists of a Precision Ball Screw through a 8:1 Reduction Gear Box for positioning accuracy. 
  • All Axis' are equipped with 3/4 HP-1800 RPM Three Phase AC Motors.


Machine Electronics and Logic Program

  • The standard SDT7 Machine features an Allen-Bradley Micrologic PLC and Programmed Motor Drives
  • Conveniently Mounted Control Cabinet
  • Configuration consists of either fixed wire or remote pendant motion control assemblies  


Machine Options

  • Power Input Set up - 240v and 480v options
  • Pressurized Mist Coolant System Integration
  • Newall 2-Axis Digital Readout System (Manual Control Models)
  • Laser Crosshair Targeting System packages
  • Wireless remote pendant control assembly
  • I-Beam Support fixture Legs for dedicated horizontal spindle drilling
  • On-site training

The new Hearn Machine production facility.  The facility allows Hearn to reduce new machine production time to under 1 month and maintain a complete machine spare parts inventory.

Model SDT7 Drill Head & Pendant
Set up for drilling flange splice plates in laydown
Hearn Machine 2011