Why McLanahan GDAMs™
McLanahan Corporation built the first Rotary Breaker in 1893. Since then, our design is an evolution of more than 100 years of rotary equipment manufacture and servicing of our customer’s units. An overlapping screen plate design is bolted to the inside of the steel cylinder beams to further strengthen and add rigidity to the cylinder, while the addition of our closure bar design eliminates the possibility of thin slabs of refuse passing through the cylinder and into the product stream.
Designed to be durable and low maintenance machines, GDAMs™ are both safe and simple to operate. The low operating speed and horsepower requirement make GDAMs™ economical to operate and easy to maintain. When maintenance is required, inspection doors in the fabricated steel and sectionalised dust housing, which covers the cylinder, allow easy access. An optional inching drive offers a safer means of rotating the cylinder for maintenance procedures. Centrally banked lubrication lines allow an operator to grease all bearings from one location.
All critical cylinder surfaces are machined during the manufacturing process in a single large lathe that allows for a concentric drum that runs vibration free and extends the overall life of the equipment. This eliminates any chances of wobble or vibration during operation. Screen plates are offered in non-plugging designs, which are installed in an overlapping fashion to protect the cylinder beams and provide additional structural support. Chute work at the feed and discharge ends ensures a smooth transition of material in and out of the cylinder.
How GDAMs™ Work
The GDAM™ consists of a large chain-driven rotating drum that is driven by an electric motor, coupling and gear reducer. The chain drive's segmented sprocket is bolted to the cylinder, allowing rotation. The cylinder is equipped with replaceable locomotive steel tires, which ride on a pair of trunnion rollers at each end of the cylinder. Thrust rollers are positioned at each end to prevent excessive axial float. When the cylinder is properly aligned, the drum will float between the thrust rollers, not ride hard to one side or the other.
The GDAM™ operates in a batch process. The cylinder is operated in a retarding non-advancing rotation. As feed material is introduced at the front end of the cylinder, it is continually lifted and dropped onto a series of perforated screen plates. This batching process continues lifting and dropping material until a signal in the control room indicates that most all of the cyrolite has been crushed. At this point, the cylinder rotation is reversed, thus discharging the accumulated refuse. Once the refuse is discharged, the process begins again.
Benefits of McLanahan GDAMs™
- All guarding is in accordance with MSHA and OSHA in the U.S. and can comply with other countries’ requirements
- Drive sprockets and chain are completely encased in steel enclosure guarding system
- Full-length base frame aids with installation and alignment
- Adjustable lifters allow for advancing or retarding the flow of material
- Renewable steel cylinder and trunnion tyres
- End sections joined by wide flange steel beams to form the cylinder frame
- Perforated and overlapping screen plate design bolted to the inside of the steel beams to further strengthen and form the cylinder
- Closure bars between breaker plates
- Four independently adjustable trunnion rollers support the cylinder ends
- Cylinder driven by a chain and sprocket utilising a motor/coupler/reducer drive configuration
Frequently Asked Questions
What are my operating costs?
The operating costs are relatively low due to the rugged design, minimal downtime and low power consumption in comparison to other machines performing similar crushing applications.
What is the typical ratio of reduction?
The ratio of reduction is quite high since the GDAM™ can except larger feed sizes. This plays a role in selecting the drum diameter, while the product size determines the length. The product size and tonnage requirement factor into the length of the breaker required for the application.
What is the role of the lifters internal to the drum?
The lifters in the drum play multiple roles. First, they lift and drop the feed material to initiate the breaking action. Second, they can be set in a neutral, advancing or retarding position. How the material is performing in the breaker will determine in what position they are set.