# Presentation: 451794

## ROOF BOLTERNOISE SOURCE IDENTIFICATION PROJECT 

## ROOF BOLTER TEAM

## FIELD STUDY AREAS

** ****SINGLE and TWIN HEAD BOLTERS**
** ****COAL and METAL/NONMETAL MINES**
** ****DRY DUST COLLECTION and WET DRILLING**
** ****FLETCHER, FMC, JOY, LONG-AIRDOX, EIMCO**
** ****SANDSTONE, SHALE, LIMESTONE, TRONA,                                                                                                                                                                                                                              VARIOUS LAMINATES**
** ****DRILL BITS ****(CARBIDE & CERAMIC)**** and DRILL                                                                                                                                                                                                                        STEEL ****(ROUND, HEX & CONSTRAINED LAYER DAMPING)**** **
** ****INITIAL and FOLLOW-UP SURVEYS                                                                                                                                                                                                                                   ****(STRAPS, CHANNELS, WORN HEADS, WATER BOXES)**

##  TWIN HEAD ROOF BOLTER Q-300 RESULTS

**ISLAND CREEK 003 Right Side**

*** *****TWIN ****HEAD**** ROOF BOLTER Q-300 RESULTS**
**WET DRILLING -vs- DRY DRILLING**
**SAME SEAM/SAME GEOLOGY/SAME HEIGHT**

**CONSOL 005/006 Right Side**

**CONSOL 005/006 Left Side**

**   ****ISLAND CREEK 003 Left Side**

*** Worked as Cont. Miner Operator for 2 hours.**

## Slide 5

## Slide 6

## *Noise Generated while Drilling Holes

****Noise Generated while Drilling Holes***

## *Noise Generated while Drilling Holes

****Noise Generated while Drilling Holes***

## Noise Generation Sources 

** ****Drilling Holes ****(2 - 4k Hz range) **
** ****Intentionally Penetrating Roof Straps (14 Gauge)**
** ****Accidental Metal to Metal contact while drilling,                                                                                                                                                                                                                (Channels & 14 Gauge Straps)**
** ****Vacuum at the Drill Pot without Drill Steel                                                                                                                                                                                                                     Inserted (**_**Drill Pot Whistle**_** in extreme situations)**
** ****Dust Collection Systems and Hydraulic Motors**
** ****Miscellaneous: Supply Loading and                                                                                                                                                                                                                               Unloading, Unstopping Plugged Steel, etc.**
** ****Background (Cont. Miner, Cont. Haulage, etc.)**
** **_**MANTRIPS**_** **

## TRAINING/WORK PRACTICES

**    ****1- Align Hole/Drill Straight Hole = 3-10 dBA drop    **
**    ****2- Minimize Crowding Steel at End of Drill Cycle                                                                                                                                                                                                                   (last 3 seconds of cycle = 3-5 dBA increase)**
**    ****3- Minimize Metal to Metal Contacts                                                                                                                                                                                                                                (Hammering Drill Steel, Dropping Materials,                                                                                                                                                                                                                     Penetrating Straps,etc.)**
**    ****4- Emphasis Identification/Repair of Worn Equip.                                                                                                                                                                                                                   (Bits,Steel,Drill Pots,Chuck Inserts, etc.)**

**TRAINING/WORK PRACTICES**

**CUT OFF MACHINE WHEN NOT IN USE - if cold,                                                                                                                                                                                                                put on a jacket, DON’T use machine as heater**

##    ROOF BOLTER MAINTENANCE

**INCORPORATE A **_**NOISE CHECK LIST**_** WITH                                                                                                                                                                                                                             THE ONSHIFT EXAM FOR DUST CONTROL                                                                                                                                                                                                                              PARAMETERS (LOOK/LISTEN FOR DAMAGED                                                                                                                                                                                                                            MUFFLERS, POT WHISTLES, BENT LEVELLING                                                                                                                                                                                                                         ARMS, WORN HEADS, LOOSE CHUCK INSERTS,                                                                                                                                                                                                                         BENT STEEL, etc.)**
**MAINTAIN PROPER TRAM CHAIN TENSION                                                                                                                                                                  **
**TIGHTEN ATRS PADS (LOOSE PADS                                                                                                                                                                                                                                   CREATE  NOISE DURING TRAMMING)**
**MAINTAIN MANUFACTURER’S SETTINGS                                                                                                                                                                                                                                ON *ROTATION SPEED AND THRUST             **** *NIOSH has conducted test comparing different rotational speeds**

## RECOMMENDED NOISE CONTROLS

*** NIOSH has conducted comparisons of various drill steels and drill bits**

**RECOMMENDED**** ****NOISE CONTROLS**

**USE SHARP *DRILL BITS TO REDUCE LATERAL                                                                                                                                                                                                                         DRIFT OF THE HOLE (**_**CURVED HOLE**_**),SIDE HOLE                                                                                                                                                                                                                      RUBBING AND DRILLING TIME (LENGTH OF                                                                                                                                                                                                                           EXPOSURE) **
*** NIOSH has conducted comparisons of various drill steels and drill bits**

## RECOMMENDED NOISE CONTROLS

**USE THE RECOMMENDED MUFFLER  AND                                                                                                                                                                                                                                INSTALL A WATER BOX AS A BACKUP                                                                                                                                                                                                                                SYSTEM (Approx. 1 dBA Drop at Head & 3-8                                                                                                                                                                                                                       dBA at Bumper - Surveyed both the Baffle                                                                                                                                                                                                                       System and the Bubble Flow Through System)**
**USE DAMPING MATERIALS IN STORAGE                                                                                                                                                                                                                                AREAS, ON TOP OF THE MACHINE  AND                                                                                                                                                                                                                              SEPARATIONS IN THE TOOL TRAY (FOR                                                                                                                                                                                                                              DRILL STEEL, TORQUE WRENCH, BOLT                                                                                                                                                                                                                               SUPPLIES)**

## RECOMMENDED NOISE CONTROLS

**RECOMMENDED**** ****NOISE CONTROLS**

**IF YOU HAVE **_**TRIED EVERYTHING ELSE**_** AND**
** ****STILL HAVE A NOISE PROBLEM WITH                                                                                                                                                                                                                                ROOF BOLTER - INSTALL A WET DRILLING                                                                                                                                                                                                                           SYSTEM (WATER  WORKS AS LUBRICANT                                                                                                                                                                                                                              MINIMIZING THE EFFECTS OF **_**SIDE HOLE                                                                                                                                                                                                                         **_**   **_**RUBBING)**_**  (3 - 10 dBA Drop)****   **

## CONTROLS UNDER STUDY 

** ****STRAPS AND CHANNELS (WAYS TO DAMPEN) -                                                                                                                                                                                                                          ****(Currently working with Shamrock Coal - April)**
** ****MANTRIP NOISE (esp. DIESEL,TRACK,UNCOVER) -                                                                                                                                                                                                                     ****(Currently working with Cave Spur - March)**
** ****CONTINUE WITH OUR FOLLOW-UP SURVEYS                                                                                                                                                                                                                             (STRAPS, MANTRIPS, WORN HEAD)- ****(Currently working                                                                                                                                                                                                                with Coastal Coal in identifying bolter maintenance problems that result                                                                                                                                                                                       in noise sources - 2nd follow-up survey in April) **
** ****MORE “TAKING CARE OF THE DRILL POT”  -                                                                                                                                                                                                                           (FEEDBACK SYSTEM **** Monterey - March****, HOTL, THICK                                                                                                                                                                                                                WALL STEEL ****Coastal Wet Drilling- March****, MIST DRILLING,                                                                                                                                                                                                         DRILL STEEL GUIDE CLAMP) **