In recent years, conventional roller screens have proved to be a sturdy and effective mechanism for the screening of fines from a crushing plant’s feed material.

With a roller screen, the separation surface is formed by polygonal discs, fitted in a staggered configuration to rotating rollers, which transport the material, circulating and loosening it. Separated fines drop through the gaps between individual rollers whilst the coarse material, assisted by the discs’ triangular shape, is conveyed via the roller screen to the overflow.

For difficult to screen, bulk material, including moist material with loamy or argillaceous shales, this type of screening appears to distinctly outclass oscillating screening machines, which frequently exhibit baking and adhesions with these materials. The rotary movement of the separation surface means that roller screens are ‘self-cleaning’ to a degree, and adhesions do not occur. In addition, each roll has scraper elements for guaranteed cleaning.

Furthermore, since a roller screen conveys the material horizontally, the downstream crusher is fed smoothly and consistently; reducing the workload for the crusher. This obviously results in reduced wear, reduced energy consumption and, in some instances a smaller crusher can be utilised. Consequently, employing roller screens generally leads to reduced energy usage, reduced operational costs, and increased operational safety.

The compact design, resulting from the horizontal material flow, as well as the variety of possible arrangement options, allows the application in numerous situations – underground as well as above ground. Plants of this type are suitable for a multitude of operations in limestone, clay, argil, coal, natural stone, salt, gypsum and other materials.

The HAZEMAG Roller Screen HRS is available as a single or multi-stage system, and with variable gap setting to meet all customer requirements.

Due to the modularisation of the roller screen length, almost any size of separation surface can be achieved.

HAZEMAG Roller Screens offer the following advantages:

• HAZEMAG Roller Screens distinctly outclass conventional screens or wobbler feeders, especially with difficult to screen bulk feed such as moist material with loamy shales or clay
• Screening effect is enhanced by use of triangular rollers which are arranged on the shafts in a staggered configuration
• Achieves spiral transportation of the material
• Separation surface is formed by discs fitted to rotating rollers
• Rollers transport the material fed in, circulate and loosen it
• Separation of the fines effected by the gaps between individual rollers
• Coarse material is transported via the screen into the overflow
• No acceleration of primary feed onto the downstream equipment due to horizontal arrangement
• Load independent and vibration free transportation of the material provides a smooth and consistent crusher feed
• As the gaps are square, elongated or flaky rocks are unlikely to pass through
• All shafts are solid core shafts
• The round shaft design allows the utilisation of adjustable and replaceable scrapers
• Clogging is minimised due to the movement in the separation surface and the resulting self-cleaning effect of HAZEMAG´s Roller Screens
• In addition, each roll is equipped with scraper elements for guaranteed cleaning
• HAZEMAG Roller Screens are available in individual modules of 4 or 6 shafts and any combination thereof
• This modularisation also allows for steps in between individual modules
• The steps between individual modules improves the screening efficiency as it increases the material movement
• HAZEMAG Roller Screens are equipped with a Chain-Link System, resulting in reduced stress to chain, sprockets, shafts and drive, eliminating the need for chain tensioning, and allowing for In-Line disc arrangement
• The HAZEMAG In-Line disc arrangement eliminates the risk that near size rocks get stuck between the gaps and impacted between shaft and 3-tier disc
• The Form-Fit system allows for individual part replacement and gap adaption
• Since 1981, over 140 HAZEMAG Roller Screens have been installed world-wide

• RORO