dozer engulfment case study l.
Skip this Video
Loading SlideShow in 5 Seconds..
Dozer Engulfment Case Study PowerPoint Presentation
Download Presentation
Dozer Engulfment Case Study

Loading in 2 Seconds...

play fullscreen
1 / 45

Dozer Engulfment Case Study - PowerPoint PPT Presentation

  • Uploaded on

Dozer Engulfment Case Study. Jack Katlic Sr VP-Fuel Supply, AEP- Retired Mark Skiles Director of Technical Support, MSHA Phil Southern Bodygard Sunnie Southern Bodygard. Dozer Engulfment Case Study. Agenda Surge Pile Hazards Surge Pile Accidents Solutions for Stronger Cab Windows

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Dozer Engulfment Case Study' - Faraday

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
dozer engulfment case study

Dozer Engulfment Case Study

Jack Katlic

Sr VP-Fuel Supply, AEP- Retired

Mark Skiles

Director of Technical Support, MSHA

Phil Southern


Sunnie Southern


dozer engulfment case study2
Dozer Engulfment Case Study
  • Agenda
    • Surge Pile Hazards
    • Surge Pile Accidents
    • Solutions for Stronger Cab Windows
    • Demonstration
    • Conclusion
    • Panel Discussion
dozer engulfment case study3
Dozer Engulfment Case Study
  • Purpose
    • Share one method the coal industry has implemented to save lives

Surge Pile Safety

Slides with the MSHA logo were adapted from the MSHA website and can be found at:

Directorate of Technical Support Mine Safety and Health Administration

surge pile hazards6
Surge Pile Hazards
  • Feeding material acts like “quicksand”
surge pile hazards7
Surge Pile Hazards
  • The edge of the drawhole is unstable
surge pile hazards8
Surge Pile Hazards
  • Poor visibility
surge pile hazards9
Surge Pile Hazards
  • Since 1980, 19 persons have died in coal mining related surge pile accidents
  • Most of the accidents have involved a hidden cavity created when material “bridged” over a feeder
causes of bridging over a surge pile feeder
Causes of “Bridging” Over a Surge Pile Feeder
  • Bridging can occur
    • When equipment transverses the material at the surface of the pile
    • Surface material compacts creating a false roadway
    • “Settling in” may occur in an idle pile and increase risk

Dozer Buried in Cavity

Note the thickness of the material that had been bridged over


Partially Buried Bulldozer in Fatal Accident in Pennsylvania

A hidden cavity collapsed under the dozer while it was pushing coal on the pile

Most fatal accidents occurred when the dozer cab windows either broke, or were pushed into the cab, allowing coal to fill the cab

Cab Filled with Coal

The coal has broken or pushed in the cab windows and filled the cab


Windshield pushed back into cab

Note: orange object under windshield is an self contained self rescuer (SCSR)

best practices surge pile safety
Best Practices: Surge Pile Safety
  • Provide equipment cabs strong enough to resist burial pressures
available solutions for stronger cab windows
Available Solutions for Stronger Cab Windows
  • MSHA initiative
    • Use of very high-strength glass
  • Massey approach
    • Add supports to the inside of the cab windows - combined with using somewhat stronger glass
  • Use of polycarbonate windows
    • Adequate strength
    • Support around edges needs to allow for higher deflection
    • Issue of scratch-resistance
  • Bodygard system
    • A customized polycarbonate system
massey subkit22
Massey Subkit
  • The first system
  • Most widely used
  • Effective in saving lives
  • System design
    • is comprised of metal bars attached to the inside of the cab
    • keep the cab and glass from collapsing on the operator

The Massey Approach

  • Installed support bars on the inside of the cab windows
  • The supports for the right-side door window are shown here

The Massey Approach

  • Horizontal support bars and additional edge support for the windshield are shown here

The Massey Approach

  • Massey’s successful burial demonstration
  • The glass cracked but it held the coal out of the cab

Contrast this scene after the Massey demonstration - where coal was held out of the cab - with...

massey subkit28

Keeps cabs from collapsing

Least expensive

Saves lives


Obscures vision especially when backing up

Causes cycildelic affects that result in complaints of headache from operators

Metal bars rattle and increase noise level in the cabin

Metal bars loosen and crack door glass that must be replaced

Massey Subkit
ppg preformed pre designed product30
PPG Preformed Pre-designed Product
  • Created as by request of MSHA to overcome the deficiencies of the subkit
  • System design
    • A chemically hardened preformed pre-designed product
    • Installed by gluing the glass into a gasket is installed in same manor as standard glass packages
field burial demonstration

Field Burial Demonstration

Federal No. 2 Mine

Near Morgantown, WV


Does not obstruct vision

Resists static pressure up to 40 psi


Preformed therefore application is limited to Caterpillar and Komatsu dozer’s* standard cab packages

Requires fixing of any deformation of the cab prior installation of the glass

Most expensive

May crack when impacted

May pop-out under stress

PPG Preformed Pre-designed Product


Pounds per square inch

*Molds are only for dozers not for end loaders

bodygard system40
Bodygard System
  • Custom engineered
  • Custom installed
  • Polycarbonate system
    • Outboard seat is created
    • Material is mechanically attach to the cab
  • Inhibits internal collapse
  • Unbreakable
  • Noise insulator
  • On site installation
  • All manufacturers
  • MSHA approved
case study history
Case Study History
  • Massey conducted drop tests of 3 systems to determine the most effective system
  • The following demonstration shows the results of the test
body guard


Does not obstruct vision

Can be made to fit anything (all makes and models of existing equipment)

Absorbs and insulates sound

Broad based system

Onsite customized installation on all cabs

Installed on site by drilling and attaching to cab

Cut to specs and attached to ensure stability


Is less scratch resistant that regular glass therefore a protective covering is applied that is easy and inexpensive to replace

Bodygard System

Body Guard

*Protective replicable material is applied to improve the scratch resistance

  • Based on the results of the drop test, Massey signed a national contract with Bodygard to perform their installations

“The Safety Window People”

1 Lincoln Center, Shinnston, WV 26431 304-592-1980