Solution Summary: Highway Milling Machines with Wet Dust Suppression
Description:
Highway milling machines use a rotating drum with teeth to grind and remove asphalt or concrete pavement prior to repair or replacement. The machines often employ a conveyor to move debris into a truck for transport to disposal or recycling facilities. Removing and conveying asphalt or concrete pavement generates a large amount of dust that may contain crystalline silica and creates a hazard for everyone in the vicinity.
Water spray systems are the most common method of controlling dust generated by highway milling machines. These controls use a pump to deliver water to the milling surface and to the conveyor where it combines with dust and silica particles and reduces airborne levels. Adding moisture to the material will also reduce the amount of dust produced downstream.
If properly designed, maintained and used, water spray systems may significantly reduce exposures near milling machines. This may reduce exposures enough that a respiratory protection program isn’t required. Continuous use may exceed the OSHA Permissible Exposure Limit, even with the use of wet dust suppression, however.
CPWR and the National Asphalt Pavement Association has produced a Field Guide for Controlling Silica Dust Exposure on Asphalt Pavement Milling Machines.
NIOSH has produced Best Practice Engineering Control Guidelines to Control Worker Exposure to Respirable Crystalline Silica during Asphalt Pavement Milling outlining measures to reduce worker exposure to respirable crystalline silica.
Volvo MT2000 Milling Machine
- Used for mill and fill or full depth removal of parking lots, city streets, county roads, shoulders, highways and airports
- Cost: call for a quote
- Engine: Cummins QSX-15, 6 cylinder, 610 horsepower
- Selectable engine speeds: 1,900 RPM (standard), 2,300 RPM (high speed) and 1,500 RPM (deep cut)
- Milling depth: 0 to 14 inches
- Cutting width: 78.75 inches (model with 86-inch drum is available)
- Conveyor capacity: up to 1,330 cubic yards per hour
- Operating weight: 80,930 pounds (full fuel, full water and 175 pound operator)
- Water spray system
- Water supplied to each conveyor and the drum
- Nozzles can be adjusted independently to match rate of work
- Water capacity: 920 gallons
Volvo MW500 Milling Machine
- Used for smaller milling jobs such as patching, joints, trenching and close cutting around street and roadway obstructions
- Cost: call for a quote
- Engine: Deutz TCD 2012 liquid-cooled diesel engine, 127 horsepower at 2,300 RPM
- Working speed: 115 feet per minute
- Milling depth: 0 to 8.3 inches
- Cutting width: 19.7 inches
- Conveyor capacity: up to 104.6 cubic yards per hour
- Operating weight: 21,020 pounds (full fuel, full water and 175 pound operator)
- Water spray system
- Water supplied via a spray bar in the drum housing
- Water capacity: 158 gallons
- Ergonomic operator station with adjustable control panel and steering wheel column
Dynapac PL350T Planer/Milling Machine
- Used for partial repairs of asphalt and concrete pavements and removing of surfaces in buildings
- Cost: contact Dynapac for a quote
- Engine: Cummins B3.3-C60, 4 cylinders, diesel, 60 horsepower at 2,200 RPM
- Working speed: 0 to 82 feet per minute
- Milling depth: up to 3.9 inches
- Cutting widths: 13.7 inches
- Operating weight: 6,170 pounds
- Water spray system
- 4 spray nozzles
- 2.5 gallons per minute
- Water capacity: 75 gallons
Dynapac PL500TD Planer/Milling Machine
- Used for removing asphalt or concrete pavements, cutting around man hole covers and road maintenance jobs
- Cost: contact Dynapac for a quote
- Engine: Cummins QSB4.5-C130, 4 cylinders, diesel, 130 horsepower at 2,200 RPM
- Working speed: 0 to 79 feet per minute
- Milling depth: up to 7.9 inches
- Cutting widths: 19.7 inches
- Operating weight: 17,860 pounds
- Water spray system
- 6 spray nozzles
- 5 gallons per minute
- Water capacity: 132 gallons
Dynapac PL2000S Planer/Milling Machine
- Used for removing asphalt and concrete pavement
- Cost: contact Dynapac for a quote
- Engine: Cummins QSX 15, 6 cylinders, diesel, 600 horsepower at 2,100 RPM
- Working speed: 0 to 131 feet per minute
- Milling depth: up to 12.6 inches
- Cutting widths: 79.1 inches
- Operating weight: 73,900 pounds
- Water spray system
- 13 spray nozzles (additional nozzles optional)
- 40 gallons per minute
- Water capacity: 980 gallons
Dynapac PL2100S Planer/Milling Machine
- Used for removing asphalt and concrete pavement
- Cost: contact Dynapac for a quote
- Engine: Cummins QSX 15, 6 cylinders, diesel, 600 horsepower at 2,100 RPM
- Working speed: 0 to 131 feet per minute
- Milling depth: up to 12.6 inches
- Cutting widths: 82.7 inches
- Operating weight: 74,700 pounds
- Water spray system
- 13 spray nozzles (additional nozzles optional)
- 40 gallons per minute
- Water capacity: 980 gallons
BOMAG BM1000/30, BM1200/30 and BM1300/30 Milling Machines
- Used for average sized pavement milling projects
- Cost: approximately $365,000
- Engine: CAT C7, 6 cylinder, diesel, 275 horsepower
- Selectable engine speeds: 1,900 RPM (standard), 2,300 RPM (high speed) and 1,500 RPM (deep cut)
- Working speed: 0 to 92 feet per minute
- Milling depth: 0 to 12.6 inches
- Cutting widths: 39.6 / 47.2 / 51.2 inches (models BM1000/30, BM1200/30 and BM1300/30)
- Conveyor capacity: up to 1,330 cubic yards per hour
- Operating weights: 42,300 to 43,300 pounds (with full fuel tanks)
- Water spray system
- 10 spray nozzles; 8 on the drum and 2 on the conveyor
- Two pumps, adjustable up to 12 gallons per minute
- Water capacity: 264 gallons
BOMAG BM2000/50 and BM2000/60 Milling Machines
- Used for average to large pavement milling projects
- Cost: $460,000 to $500,000
- Engine: Deutz/TCD2015, 8 cylinder, diesel, 1,900 RPM
- Milling depth: 0 to 12.6 inches
- Cutting width: 78.7 inches
- Theoretical milling volume:
- Water spray system
- 14 spray nozzles; 12 on the drum and 2 on the conveyor
- Two pumps, adjustable up to 30 gallons per minute
Model | Horsepower | Working Speed, feet per minute | Operating Weight*, pounds | Water Capacity, gallons |
BM 2000/50 | 469 | 0 to 112 | 65,257 | 713 |
BM 2000/60 | 590 | 0 to 98 | 71,650 | 872 |
*Operating weight with a full fuel tank
Risks Addressed:
Milling asphalt and concrete pavement is a high dust activity that, in the absence of controls, would place workers at risk of lung disease, cancer, chronic obstructive pulmonary disease (COPD), lung scarring and silicosis with prolonged exposure to silica. Silicosis is an incurable, sometimes fatal disease.
How Risks are Reduced:
In a similar evaluation, Linch reports personal sampling results ranging from 0.22 to 2.9 mg/m3 for respirable dust and from less than the detection limit to 0.36 mg/m3, seven times the REL and 14 times the TLV, for respirable silica.
Effects on Productivity:
Reducing airborne dust levels reduces vehicle and site cleanup times and avoids exposing other workers, members of the public, adjacent property, cars and building occupants, which can increase liability and time-consuming disputes. Improved worker comfort is a result of reduced airborne dust which may in turn result in less fatigue for the worker and greater productivity. In some cases, particularly where highway milling is intermittent, the use of water spray systems may be adequate to reduce the need to wear a respirator, and the need for an employer respiratory protection program.
Additional Considerations:
As is the case with any construction equipment, users should follow manufacturer safety recommendations and comply with any applicable local, state or federal regulations.
Availability
BOMAG Milling Machines
To obtain information, visit http://www.bomag.com
or contact 1-309-852-6219 info.bomag@bomag.com
Dynapac Planers/Milling Machines
To obtain information, visit http://www.dynapac.com
or contact 1-210-474-5770
Volvo Milling Machines
To obtain information, visit http://www.volvoce.com
or contact 1-828-650-2000 http://www.volvoce.com/constructionequipment/na/en-us/aboutus/contactus/contact_new/Pages/contact_equip_request.aspx