PMCA Rotary Feeder
PMCA Rotary Feeder
A high-capacity rotary feeder for introducing cement raw materials, principally quarried limestone, into a vertical roller mill (VRM) or other type of raw mill. Designed for throughputs from 150 to 1000 tons per hour, the PMCA feeders are built to operate for a 24-month cycle between rebuilds.
Unplanned outages are virtually eliminated and the tight internal clearances lower energy costs in the milling operation.
Key Advantages
- Very little unplanned downtime to disrupt operating plans or production targets; a PMCA-60 recently had >99.8% uptime over a two-year operating cycle.
- Two-year operating cycle between rebuilds should be expected, reduces costs and allows for feeder removal only every other year in the annual outage.
- Install it, start it up, and run it – the PMCA requires only periodic maintenance and none of the adjustments or parts replacements that are common on other raw material feeders.
- Separator horsepower and power consumption are expensive and false air intrusion drives up costs; the tight tolerances in a PMCA reduce false air by thousands of CFM compared to other feeders.
- Lower false air reduces turbulence in the mill which leads to more uniform grinding and consistent particle size.
- Compact design makes the PMCA a “universal replacement” for feeders from others – minimizing installation complexity and cost.
Problems Solved
Raw mill outages are disruptive to achieving operating plans and a prolonged outage can shut down the plant’s entire output; a reliable raw material feeder is critical to keeping the mill operating.
PMCA feeders can normally be rebuilt after a two-year service cycle which can substantially reduce total cost of ownership over a multi-year horizon compared to an annual rebuild or an annual new feeder purchase.
How Does It Work?
Depending on the feeder size, 1” or 1-1/2” thick Tri-Braze abrasion-resistant steel used to construct the barrel resulting in exceptional durability and making rebuilding possible.
Six-pocket rotor with rounded rotor pockets to minimize possible build-up of wet or sticky raw materials.
Rotor constructed of 1” thick Tri-Braze abrasion-resistant steel for durability.
Rotor body and main drive shaft are joined with taper-locks and Ringfeder shaft clamps for positive rotor location and to allow the replacement of one or the other independently.Housings and rotors precision-machined for a clearance of 0.045” to 0.075” per side – depending on the size of the feeder.
Standard equipment includes MSHA/OSHA-compliant shaft guards, an Allen-Bradley zero speed sensor, and a split-ring shaft packing gland for easy service.
Oversize drive shaft and heavy-duty Dodge FCE piloted flange bearingsNord Clincher or MaxxDrive (depending on feeder size) shaft-mounted gear-motor drive packages including integrated Tsubaki torque-limiter clutches.
