Key Benefits

  • Long wear part life
  • Low operation and maintenance costs
  • Short shutdown for wear part replenishment
  • Up to 20-30% reduced energy consumption

High capacity High Pressure Grinding Rolls for all your use cases

During its relatively short history in minerals processing, HPGR technology has undergone significant development in machine roll wear surfaces and control philosophy. Initially introduced as a cement industry product in the mid 1980s, HPGRs soon gained a (minerals processing) foothold in diamond mines.

By the late 1990s the HPGR became standard equipment for processing iron ores. Successful hard rock mining installations followed about a decade later and HPGR applications have been expanding into base and precious metals flowsheets around the globe ever since, as the technology continues to prove itself on more complex and harder ores. There are several motivating factors that contribute to HPGR consideration for minerals processing:

There are several motivating factors that contribute to HPGR consideration for minerals processing:

  • Metallurgical benefits
  • Power savings
  • Reduction in wear costs
  • Reduced water consumption
  • Small footprint (allows for easy retrofits/upgrades)
Designed with your operation in mind, the HPGR truly is a unique comminution product when compared to traditional grinding mills and fixed-gap crushers. This makes it a perfect complementary tool to work in conjunction with, and even enhance the performance of, these other machines. With HPGR technology, the feed material is exposed to very high pressure for a short amount of time. The compressive nature of the HPGR mechanics causes the rock to typically crack and cleave along the grain boundaries, weakening the rock structure and exposing the ore particles. This high pressure also creates a large number of fines and causes the formation of microcracks in the larger particles.

We offer three frame designs for the minerals processing industry:

  • P-Series (P150): a small scale lab/pilot unit 
  • S-Series (S360 & S900) : our standard frame for smaller projects, similar in appearance to our legacy cement machines
  • F-Series (F1300, F1600, F2500, F3200, F3900, F5000, & F6000): specifically designed to accommodate the heavier loads of larger plants/units

High Pressure Grinding Roll - saving energy and providing results

Long wear part life
Our HGPRs are specially equipped with durable wear parts that are made to last longer and get more done for you in your operation. Many have found the long wear part life within our High Pressure Grinding Mills saves them time and money.
Low operation and maintenance costs
The initial investment in a high capacity High Pressure Grinding Mill certainly pays off. The superior construction and energy-efficient capabilities of the machine mean lower costs to operate and maintain. Low cost to you means higher margins.
Short shutdown for wear part replenishment
You simply can’t afford to shut your operation down frequently to replace wear parts. The wear parts within our High Pressure Grinding Roll are long-lasting, but also very easy to replace when they do wear down.
Up to 20-30% reduced energy consumption

Energy efficiency is key to running a profitable operation, so saving 20 to 30% could pay huge dividends. We do our part by providing you with an HGPR that’s built to conserve energy and save you money.

Efficient and advanced crushing with High Pressure Grinding Rolls

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 the Express Frame, accommodates the need to handle and operate larger and heavier components. 

Our Express Frame is designed and built for a faster and safer replacement of the roll surfaces. With the minerals processing industry always trending towards larger equipment, the Express Frame has been developed specifically with consideration for handling these larger, heavier components in a more safe and easy manner. 

The new design offers a tapered pin and bushing concept. Removal of the tapered bushing creates more clearance space for inserting and removing pins. This design utilises a wedge jacking system to take the load off the pins for quick extraction and replacement.

Advanced skew control

Designed for your needs, the FLSmidth HPGR features Advanced Skew Control (ASC) via the hydraulic pumping system to the cylinders and monitored by linear variable differential transducers (LVDTs). 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 allowing them to adjust to the segregation of feed conditions over the roll width, especially for larger machines.

Hinge-mounted, dual-acting cylinders

Mounting the hydraulic cylinders to the frame with hinges allows maintenance personnel to safely access and inspect these components without getting inside the framework of the HPGR. Should these cylinders need to be removed, overhead access to these heavy components is free and clear of the frame with hinges in the outboard position. 

“Dual-acting” means that no special tools are required for separating the rolls in the event of a tramp metal occurrence. By simply reversing the oil flow, the hydraulic cylinders can be used to retract the rolls allowing the tramp to fall through, getting the machine back on line quickly.

Oil-cooled bearings

Low pressure oil is pumped from the reservoir, filtered, temperature-conditioned, and routed to each of the shaft bearings. This system supplies filtered and cooled oil to the bearings flushing away contaminants and carrying away heat that is generated during normal operation of the HPGR.


  • No greasing/cleaning required
  • Longer bearing life (vs grease packing)
  • No additional shaft cooling required

Advanced drive systems

The two roll shafts are powered by induction motors driving planetary gear reducers. The gear reducers are mounted to a common torque-sharing arm assembly, thus eliminating the need for mounting these components to a foundation. 


The drive motors are synchronised using encoders in a master-slave drive arrangement. Two motors each with a variable frequency drive (VFD) seek to control the speed and torque for both of the roll assemblies for even wear, and a prolonged wear life. 


Cardan shafts connect the main drive motors to the high-speed reducer shafts via torque-limiting couplings. These torque limiters are manually-engaged and critical for protecting the drive and HPGR components in the event of an overload situation. 


Rigid drive couplings attach the reducer output shafts to the roll shafts completing the drive system.

Design analysis

Every HPGR we supply is backed by a full complement of design analysis:

  • Finite Element Analysis (FEA)
  • Seismic Analysis (as required)
  • Drive Train (Torsional) Analysis
  • Vibration Analysis
  • Gearing Designed to AGMA Standards
  • Field-tested Wear Surfaces

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