High Pressure Grinding Roll for advanced crushing |FLSmidth

Key Benefits

Lower operating power required
Creates microcracks for downstream processes
Provides a more stable grinding operation for variable ores
Reduces the need for and consumption of grinding media

What we offer

HPGR - Today's technology for today's mines

Our HPGR is flexible enough to be highly suitable for both brownfield expansions and greenfield installations. The wide variety of ways our customers are already using the machine shows just how helpful the technology is.

Our HPGR is a perfect complementary tool to work in conjunction with, and even enhance the performance of traditional grinding mills and fixed-gap crushers. The HPGR exposes feed material to very high pressure for a short amount of time. The compression typically causes the rock to crack and cleave along the grain boundaries, weakening the rock structure and exposing the ore particles. This high pressure also creates a large amount of fines and causes the formation of microcracks in the larger particles, lowering the Bond work index of the ore and reducing the ball mill power required downstream.

High pressure grinding roll - saving energy and providing results

The HPGR truly is a unique comminution product. It weakens rock structure and exposes ore particles, making it an attractive option for heap leach applications.

HPGR in Pebble Crushing Circuit

HPGR for Heap Leach Circuits

HPGR in Finish Grinding Circuit

Primary Grinding

HPGRs add efficiency to the primary grinding circuit for highly competent and complex ore bodies. HPGR product has microcracked particles which weakens the boundaries and lowers the Bond work index. This reduces the amount of ball milling power required downstream.

Pebble Crushing

Our HPGR is great at de-bottlenecking your problematic pebble circuit. You know how easy it is for hard pebbles to get caught in circulation, small enough to escape the mills but too large to make it through your screening process. Our solution is to crush the pebbles with a cone crusher and then feed them to an HPGR. This arrangement will crush the pebbles enough that that you can feed the product directly into the ball mill sump.

Heap Leaching

If higher recoveries and faster leach kinetics is important to you, HPGR should be a consideration for your heap leach flowsheet. The microcracking in HPGR product lends itself nicely to the heap leaching process. HPGR inclusion in heap leaching can be a viable retrofit to existing operations as well as for original plant designs.

Finish Grinding

The future of mining is dry comminution circuits that minimise wasted power, water consumption and carbon production. This circuit also provides downstream benefits:

The consumption of grinding media is eliminated
The finished, ground material can be immediately stored, creating a buffer, and allowing the downstream plant to be fed at a consistent rate
Air separators provide a product with a narrower particle size distribution

Benefits of our HPGR in minerals processing:

Improved metallurgy due to microcracking of coarse particles
HPGR is one of the most power efficient tools in comminution
Higher availability than conventional crushers
Reduced need for and consumption of grinding media
More stable grinding operation for variable ores

Product features

Efficient and advanced crushing with High Pressure Grinding Rolls

Oil-cooled bearings

The HPGR has a skid mounted tank with a lubrication oil conditioning system that supplies clean filtered and temperature conditioned oil to the roll bearings. A constant flow of oil carries the contaminants and heat that are generated in operation away from the bearings to maximising uptime. The lubrication oil system instrumentation monitors and protects the system. In contrast, conventional grease lubricated units are messy, require frequent relubrication and must be water cooled.

Key takeaways

No greasing or cleaning required
Longer bearing life
Grit and heat are quickly removed from the bearings

Advanced skew control

We designed the hydraulic pumping system to the cylinders with advanced skew control (ASC) and use linear variable differential transducers (LVDTs) to monitor the system. As skewing starts to occur in the floating roll, the ASC system adjusts the press force applied to the hydraulic cylinders, keeping the roll assemblies as near parallel as possible during operation, while at the same time maintaining interparticle contact and grinding efficiency over the roll width.

Differing frame types for specific applications

There are two frame styles offered for industrial applications. The S-Series, which incorporates a traditional box frame design, has been optimised for smaller plants. The F-Series, using our express frame, accommodates the need to handle and operate larger and heavier components.

We designed and built our express frame for a faster and safer replacement of the roll surfaces. With the minerals processing industry trending towards larger equipment, we specifically developed the express frame to handle larger, heavier components in a safer and easier manner.

This new frame uses a tapered pin and bushing concept. Removal of the tapered bushing creates more clearance space for inserting and removing pins. A wedge jacking system takes the load off the pins for quick extraction and replacement.

HPGR Standard
Sizes	Type	Roll Diameter [mm]	Roll Width [mm]	Grinding Force [kN]	Motor Power [kW]	Length [mm]	Width [mm]	Height [mm]
PM0	9/7	950	650	2,700	2x220	3,240	1,860	3,800
PM1	11/8	1,100	800	3,400	2x450	3,750	2,150	4,600
PM2	14/8	1,400	1,000	4,300	2x500	3,735	2,164	5,400
PM4	17/10	1,700	1,000	7,000	2x800	4,490	3,030	6,800
PM5	20/10	2,000	1,000	8,600	2x1,600	5,950	3,000	7,500
PM6	20/15	2,000	1,500	11,000	2x1,850	6,020	3,460	8,000
PM7	20/17	2,000	1,650	13,500	2x2,500	6,550	3,640	8,800
PM8	24/17	2,400	1,650	17,000	2x2,800	7,725	3,820	9,000
PM9	26/18	2,600	1,750	20,000	2x3,400	8,500	4,150	9,700
PM10	30/20	3,000	2,000	25,000	2x5,000	9,500	4,600	11,000