Model HDDR & CHDDR


Dual Head Roof Bolter - Walk-Thru Chassis

Fletcher Model HDDR brings greater flexibility than ever to your high seam operation. Heavy-duty boom swing from 4’ to 20’ to allow several bolt installations from a single chassis position. Booms allow operators to drill over rubble, near ribs and over otherwise loose bottom areas. Bolting pattern is established relative to the roof, not the floor.

Standard 90° mast tilt allows angle and rib drilling: Fletcher ATRS (Automated Temporary Roof Support) eliminates the need for temporary posts and jacks in most applications.

  • Walk-thru chassis reduces miner exposure to rib hazards.
  • Operates in seam heights of 6’ to 17’ (custom heights available).
  • Dual heads install a full row of bolts from a single chassis position.
  • High-strength elevating booms drill without direct support from floor below.

Material Handling System

Mechanized mesh rack and mat rack as well as winch on material pods facilitate loading, storing, and operator access to the supplies. The mesh is delivered to the rear of the machine where the bolter operator winches the shifts supply of mesh into place using the radio control. The material pods are vendor loaded above ground and delivered to the rear of the machine. The operator uses the radio control to winch that days supply of consumable materials on to the bolter. The empty pods are off loaded and returned to the outside to be reloaded.


General Specifications

  • Electrical System

  • MSHA approved electrical system.
  • Dual 50-hp AC motors.
  • Horizontal axis cable reel.
  • Intrinsically-safe strip-type panic bars with start switches at all control stations.
  • Dust Collection System

  • MSHA approved vacuum system for hollow-shaft drill steels.
  • Blower: rotary lobe type, 62 cfm.
  • Vacuum at drill head: 12” Hg, separate system for each drill unit.
  • Hydraulic System

  • Maximum working pressure: 2500 psi.
  • Reservoir capacity 180 to 200 U. S. gallons.
  • Filtration: magnetic intank, Pall high pressure.
  • Hand-operated fill pump with screened intake.
  • JIC hose fittings.
  • Dual pumps.
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  • Drive System

  • 4-wheel chain drive.
  • Tractor type steering.
  • Turns within length.
  • Staffa tram motors with motion control valves.
  • Automatic spring set, hydraulic release disc brakes
  • Tram speed: 0-1.5 mph
  • Foam filled tires.
  • Drilling System

  • Linear sumping booms.
  • Telescoping mast feed.
  • Thrust: 0-7000 lbs. (optional 10,000 lbs.).
  • Feed length: 70” to 90” depending on mast size.
  • Torque: 0-300 ft. lbs.
  • Drill rotation speeds: 0-560 rpm.
  • Feed rate: 0-36 fpm;
  • Boom extend: up to 24”.
  • Minimum drill head separation: 4’.
  • Maximum drill head separation: 20’.
  • Adjustable bolt torquing valve.
  • 2 stabilizer jacks on frontof chassis.
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  • Standard Equipment

  • 90° mast tilt with hydraulic drill guides
  • Independently elevating booms
  • Automatic disc brakes
  • Automated Temporary Roof Support (ATRS)
  • Automatic disc brakes
  • Cable reel
  • Intrinsically safe strip switch panic bars
  • Deep chuck drill heads
  • MSHA "2G" Approval
  • MSHA approved illumination
  • MSHA approved dust collection system
  • MSHA approved fire suppresion
  • Foam filled tires
  • Fore-aft mast tilt
  • Features

  • Boom Swing
  • Boom Sump
  • Boom Lift
  • Overall Length
  • Overall Width
  • Chassis Height
  • Ground Clearance
  • Weight
  • 10' either side of center
  • Up to 24" (610mm)
  • Up to 60" (1524mm)
  • 24'6" - 27' (7468-8230mm)
  • 8'6" - 11' (2591-3353mm)
  • 3'6" - 6' (1067-1828mm)
  • 10" - 15" (254-381mm)
  • Avg. 60,000 lbs. (27216kg)

Download the Spec Sheet

HDDR Specifications Sheet | This document requires Adobe Reader.
J. H. Fletcher & Co.™ cannot anticipate every mine hazard that may develop during use of these products. Follow your mine plan and/or roof control plan prior to use of the product. Proper use, maintenance and continued use of (OEM) original equipment parts will be essential for maximum operating results.