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DBT Roof Bolter

DBT Roof Bolter
Start of Shift Pre-op mantrip Enter mine Conduct workplace examination Pre-op of Roof Bolter Tramming/Place Change Tramming Bolter from Inch Tram Controls Drilling Test Hole Drilling and Installing Bolts Installing a Control Rod End of Shift Activities Unusual/Non Routine Activities
1. Start of Shift
Get dressed
Blouse pants
All clothing should be snug fitting, especially shirt sleeves
Obtain PPE Priority 2
Safety glasses
Hearing protection
Gloves
Knee pads
Hard hat
Safety boots
Check SCSR Priority 3
Self-rescurer must either be worn or within 25 feet of you at all times
Pull out of case Priority 3
Check for physical damage Priority 3
Seals and dents
Check moisture indicators Priority 3
Indicators should be blue when good
Obtain methane detector Priority 3
Check for physical damage Priority 3
Lens, dents, screen blockage,
Test battery Priority 3
Push both buttons to test Priority 3
3.4 minimum reading
Test electrical zero Priority 3
Push right button Priority 3
Reading should be 0.0 or 0.1
Obtain cap lamp Priority 3
Check water level
Check two beams
Check lens lock
Check cord
Abrasions
Cuts
Check white board and assistant notes Priority 2
Tools needed
Supplies needed
Roof conditions
Equipment conditions
Mining cycle location
Obtain needed supplies Priority 2
Obtain steels Priority 2
Obtain wire
Obtain signs Priority 3
Obtain bits Priority 2
Obtain filters
Obtain nails
Obtain spads
Obtain hand tools
Hammer
Razor knife
Adjustable wrench
Channel locks
6 inch flat screw driver
Electrical tape
Allen wrench
Check in/Tag in
2. Pre-op mantrip
Check lights
Check panic bar Priority 2
Check brakes Priority 3
Check brakes second time on the ramp prior to going into pit
Check charge indicator, if applicable
Check for fire extinguishers
Two fire extinguishers
Check for jack and lifting bar
Clean reflectors
Clean off debris
3. Enter mine
Conduct travelway examination
Put safety glasses on
Observe for mobile equipment Priority 2
Check roof conditions Priority 2
Check for cracks, loose rock, taking on weight, water
Check for loose ribs
Check for overhang
Check for ledges
Check for spalling
Look for uneven bottom Priority 2
Rough spots and bumps in the road
Soft spots/low spots
Look for roadway debris Priority 2
Look for crib blocks, rock, banding material, cable, bolts and knocked out timbers
Check for damaged bolts
Correct and/or report any unsafe conditions Priority 2
Exit mantrip
Be aware of crawling hazards
Obtain glue Priority 2
Drop glue off at intake supply car
Travel to return supply car to drop off glue
Take canvas down
Anytime back check/line curtain is taken down, replace canvas after traveling through
Replace canvas Priority 2
Travel back to intake and park mantrip in the intake
Restore canvas
Use only a permissible mantrip
Contact section foreman for bolting cycle
Load supplies if needed
Empty dust box Priority 2
Face bolter inby Priority 2
Stay out of this dust
Open box
Stay on the intake side of box Priority 2
Tap the filters out Priority 2
Replace filters if necessary
Once filters can not be tapped out, replace filters
Clean box out with hoe
Clean seal
Close door
4. Conduct workplace examination
Look for section foreman pre-shift date, time, and initial
Workplace exam must be conducted before a bolter moves into a new place
Check line curtains Priority 2
Examine roof conditions Priority 3
Start at outby corner of last open crosscut
Check for cracks, loose rock, taking on weight, water
Scale loose top with slate bar, if necessary
Spot bolt any area that can't be scaled
Check for loose ribs
Start at outby corner of last open crosscut
Cracks
Ledges
Spalling
Support or scale any loose ribs
Check for methane with spotter, and probe where necessary Priority 3
1 inch from face/roof/rib
If magnet on head of miner is not used you must use a probe
Check for damaged bolts and wide bolt spacing
Correct and/or report any unsafe conditions Priority 2
Ensure danger unsupported roof signs are hung where roof is unsupported Priority 3
In low coal, it is very easy to accidentally travel unsupported roof. These signs make it much easier to identify unsupported roof.
5. Pre-op of Roof Bolter
Check cable
4 splices, 5 to end the shift
Adequate cable for the shift
Adequately hung
Nicks, abrasions
Pull from reel if necessary
Check for accumulations
Coal dust
Spilled oil
Grease
Empty boxes, garbage, etc.
Check fire suppression
One in kitchen
One in the front of the machine near the operator station
Do not activate
Check panic strips Priority 2
Check all three panic strips
Start the machine and tap Priority 2
Check controls
Ensure controls are self centered
On some older machine, the cable reel lever may not self center
Check for excessive play
Keep linkage free from obstructions
Check lights
Report any lights that are out to foreman or mechanic
Check tires
Look for missing tire tread
Check for tools
Rock bar
Hammer
Torque wrench
Probe
Check suction
6. Tramming/Place Change
Ensure everyone is clear Priority 3
Check inch tram
Check ATRS Priority 2
Raise ATRS and pressurize Priority 2
Be observant for broken pins, cracks, and bleed-offs
Check for bleed-off Priority 2
Bleed-off is when the ATRS will not stay pressurized when against the roof
Lower ATRS
Check boom
Check rotation
Check suction
Raise stab jack
Turning the machine right and left, pull ample slack cable from reel Priority 2
Ensure gas tests have been made in face area before entering last open crosscut Priority 3
See workplace exam
Get in kitchen Priority 2
Ensure entire body is in kitchen Priority 2
Keep all body parts inside kitchen
Check cable reel to ensure that it is off Priority 2
Center machine in entry
Stay as low as possible in the kitchen Priority 2
Beware this machine may teeter and roof out
Look ahead for obstruction on travelway Priority 2
Overhead clearance
Bottom obstructions
7. Tramming Bolter from Inch Tram Controls
Ensure cable reel is disengaged Priority 2
Locate last row of bolts Priority 3
Make visual assessment of cut Priority 3
Inch tram forward to last row of bolts
Tram bolter so that the right rear corner is closer to the right rib Priority 3
Have roof control plan diagram showing the placement of the machine in the roof bolter cycle
Position the drill head of the machine so it is within 4 feet of the last row of bolts or closer, and within 4 feet of the rib or closer Priority 3
Roof conditions will dictate the exact distance of the bolt spacings
8. Drilling Test Hole
Drill proper length test hole according to roof control plan Priority 3
You can always drill higher than the roof control plan requires
Review approved roof control plan and/or mine policy for exact location of test holes
Watch for steel to jump Priority 3
This comes with experience
Jumping indicates bed separation
Look, listen, and feel for changes in the roof Priority 3
This comes with experience
Roof may sound drummy or hollow
Drilling sound will change as you go through different laminations
Measure test hole
Drag tip of tape measure against side of hole while withdrawing
Catches with the tip of the tape measure indicates separation or cracks
Install proper length bolt and identify Priority 2
Mark test hole Priority 2
Paint test hole or bolt installed in test hole
This allows people to know where test holes are located
Leave test hole open and identify Priority 2
Optional, to install a correct size bolt
Notify section foreman of roof defects to determine supplemental support if you are unsure Priority 3
Will determine course of action
Determine the length of bolts Priority 3
All bolts must anchor in solid roof. See roof control plan
9. Drilling and Installing Bolts
Visually examine the roof Priority 3
If roof is visually defective, do not sound
Look for dribbling, cracks, cutters, clay veins, horsebacks, etc.
Advance bolter not more than 4 foot from last row of bolts Priority 3
Do not expose yourself to unsupported roof
Raise ATRS Priority 3
ATRS must make contact with the roof
Properly position bolter Priority 3
Within 4 feet from the rib and the last row of bolts
See diagram from he roof control plan on bolting sequence
Set canopy and stab jack Priority 3
Make sure the canopy and stab jack are pressurized
Take assembled bolt, bearing plate, and resin Priority 2
Sound roof Priority 3
Unless obviously bad
Use suitable device to sound the roof
Listen for drummy or hollow sound
Keep all body parts away from the drill boom Priority 3
Lower drill head to bottom
Place starter steel in chuck
Raise head until bit contacts roof Priority 2
Drill steel must be straight or plumb to correctly drill your hole
Remove your hand from the drill steel Priority 3
Slowly rotate steel until bit penetrates rock while raising the drill head Priority 2
Increase drill speed
Increase up pressure so that steel penetrates rock without clogging
Drill starter hole to proper depth
Look and listen for changes in roof
Lower drill head to bottom with slow rotation and remove starter steel
Varies with type of steel
Insert finishing steel in existing hole
Insert pusher steel into chuck
Allow finisher steel to drop and couple with the pusher steel Priority 2
Remove you hand from the drill steel Priority 3
Increase drill speed and pressure to drill the maximum depth Priority 2
Pusher steel must be marked to ensure the proper hole depth which is 1 inch deeper than the bolt to be installed
Slow rotation
Lower drill head to bottom
Remove steels Priority 3
Do not put your hand or arm directly underneath a hole with steels in them
Place steels in steel quiver
Insert resin into hole Priority 2
Insert bolt with plate already assembled Priority 2
Using the boom, push bolt 1 inch from roof Priority 2
No rotation should be used at this point
Drop boom
Insert wrench
Wrench may not be used with hex steels
Seat wrench firmly on bolt Priority 2
Rotate maximum speed for recommended mix time Priority 3
Over mixing can be just as bad as under mixing. Count by saying one thousand one, one thousand two, etc.
Stop rotation and push to roof with maximum thrust Priority 3
Hold pressure for recommended hold time Priority 3
Spin time and hold thrust time are on each box of resin
Drop boom with wrench
First bolt in each cut must be torque Priority 2
See roof control plan
Follow roof control plan for bolting sequence Priority 3
Following the pre-established roof control bolting sequence gives you maximum protection from your ATRS and already installed bolts
Set bolter so that the right rear corner is closer to the right rib Priority 3
Have roof control plan diagram showing the placement of the machine in the roof bolter cycle
Make gas test at intervals not to exceed every 20 minutes Priority 3
Extend line curtain as bolts are advanced Priority 2
Normally it is acceptable to have curtain up to the rear of bolter unless concentration of methane requires the canvas to be closer
Keeping an unsupported roof sign behind the curtain Priority 3
In low coal, it is very easy to accidentally travel unsupported roof. These signs make it much easier to identify unsupported roof.
Hang curtain to within 10 feet of face when bolting is concluded Priority 2
Normally it is acceptable to have curtain up to within 10 feet of face unless concentration of methane requires the canvas to be closer
Makes the area safer for the scoop operator
Bending 6 foot bolts
Place bolt on slight angle with head end on bottom
Place knee on the crimp point
Press with your knee
Pull the end of the bolt upward until you reach 45 degree angle
Pick the head of the end of the bolt up
Place your knee on the crimp
Press with your knee
Pull the head end until you reach a 90 degree angle
The bolt when pulled properly will appear like a "U" shape
Install plate Priority 2
Bending 42 inch or similar bolts
Place bolt end in square stock on the bolter designed for bending
Slide bolt in to the desired length
Push head end down toward bottom
Stop when you have about a 25 degree bend
Over bending will create drag while inserting bolt into hole. This makes it very difficult to get the bolt inserted, and may result in hangers
Install plate Priority 2
10. Installing a Control Rod
Follow all procedures outlined in drilling and installing bolts, except using a bearing plate Emergency
Install control rod at intervals not to exceed 100 feet in solid roof
The installation of control rods are not required where full grouting can be observed at the intervals required in the roof control plan
Install control rods at 50 foot intervals in subnormal roof
Drill control rod hole to the same depth as normal roof bolt hole
Determines if there are voids in the roof into which resin is being lost
Drill control rod hole out of pattern
Install a normal length bolt without a bearing plate
This allows you to measure up into the hole for resin
Insert the bolt to within 1 inch of roof
Mix resin according to manufacturer recommendations
Look for a show of resin at the bolt head
Contact foreman if there is no show of resin Priority 3
Adverse or unusual roof conditions must always be reported to the foreman
11. End of Shift Activities
Assure danger unsupported roof signs are hung Priority 3
In low coal, it is very easy to accidentally travel unsupported roof. These signs make it much easier to identify unsupported roof.
Hang line canvas to the second to last full row of bolts outby the face Priority 2
Tram bolter to supply cars
Hang bolter cable, if necessary Priority 2
Check with foreman for further instructions
Let foreman know what supplies are needed
Inform foreman of any roof changes/machine problems
Load bolter with supplies
Gather and remove any damaged resins and used bits Priority 2
Put bits in used bit container
Dispose damaged resin in garbage container
Review the MSDS sheet with the trainee
Go to mantrip and conduct head count Priority 2
Travel outside
Look for hazards in travelway Emergency
See entering mine Emergency
Talk to cross shift bolters about conditions and bolter maintenance Priority 2
This could be in the section, on the travelway or outside
Park mantrip in pit shop
Set panic brake Priority 2
Shut light off
Place on charge Priority 2
Go directly to shower house and tag out
Put your light on charge Priority 2
Place methane spotter on charge Priority 2
Make notations on white board as needed Priority 2
12. Unusual/Non Routine Activities
Gas detection 1 percent or greater
Shut down Priority 2
De-energize your machine Priority 2
Notify foreman Priority 2
Follow foreman's instructions to make changes in the ventilation system Priority 2
Retest for gas prior to restarting Priority 2
Gas detection 1.5 percent of greater
Shut down Priority 3
De-energize your machine Priority 3
Notify foreman Priority 3
De-energize power to the entire section Priority 3
Follow foreman's instructions to make changes in the ventilation system Priority 3
Retest for gas prior to restarting Priority 3
Installation of supplemental support
Identify signs of roof failure in which supplemental support is necessary Priority 3
Danger area off Priority 2
Get instructions from foreman Emergency
Start bolting 8 feet outby in solid roof Priority 3
Position bolter to provide maximum protection with your ATRS Priority 3
Install supplemental supports according to plan Priority 3
Evaluate roof continuously during any supplemental support installation Priority 3
Monitor areas where supplemental supports were installed Priority 2
Areas inby or outby the supplemental area may need additional attention
Firefighting and evacuation
Roof bolter duties obtain; fire extinguishers, rock dust, and take to the intake side of the fire Priority 3
Quick response in attacking a fire lessens the possibility of the fire getting out of control