Grinding technology for plane bricks
KELLER ICS grinding machines can handle both dried and fired bricks, grinding them to get a plane surface on both sides. The cut surfaces are ground with diamond grinding wheels in a continuous process. Due to the modular system, KELLER ICS can offer the optimal grinding machine to meet the requirements of the customer. The machine is either available with 1 or 2 grinding stations with a standard diameter of 650 mm, or the customer can choose from a grinding size range between 199 mm to 500 mm. The grinding capacity depends, amongst other things, on the brick size and the material used. An exchange of the grinding wheel can be done in no time.
Modular grinding machine system
All machines are characterised by a high technical availability and serviceability. The standard grinding machine type is designed for brick heights from 115 to 380 mm. The transport speed of the bricks is continuously adjustable between 1.5 and 18 m/min. This modular system offers a future-oriented solution to the customer as he can retrofit his machine with the mentioned options at any time. Therefore, with a KELLER ICS grinding machine you have the option to react in a very flexible way to future developments on the brick market. In addition, it is generally possible to deliver customer-specific special solutions.
Design of the grinding machine
The large mass of the stable base frame and the use of vibration dampers ensure that the machine runs smoothly.
Two separately driven lateral inlet belts centre the bricks and transfer them to the transport system of the grinding machine. The feeding belts adapt automatically and symmetrically to the raw brick.
Lower transport system
The well-established wear-resistant transport system developed by KELLER ICS facilitates precise guiding of the passing bricks. The elastic support on the transport belt compensates for any unevenness of the bricks. Servo motors used as a standard allow optimal adjustment of the transport speed.
Upper transport system
The upper transport system is of the same design as the lower one. A motorised spindle adjustment moves the transport belt to its home position. Pneumatic cylinders and the elastic support of the transport belt compensate for any tolerances in height of the bricks. The contact pressure can be adjusted to the exact value required.
The servo drives of the feed system permit exact positioning and fast movement of the grinding wheels.
The grinding tools are positioned by a patented laser measuring system that was especially developed for this task. All measuring values are not taken on the outgoing bricks but directly at the grinding wheels. This method leads to a very high accuracy and easy adjustment of the grinding size.
Each grinding wheel pair is separately enclosed to prevent dust formation. The grinding wheels are easily accessible after opening the hoods.
Cleaning the plane bricks
After grinding, the brick dust is blown away from the plane bricks, extracted by suction and forwarded to a central de-dusting installation.
- Accessibility of the complete installation even during operation
- Available optionally with 2 or 4 grinding heads
- Cutting lengths from 199 – 500 mm can be implemented with additional equipment.
- All drives, e.g. grinding wheels and transport belts are frequency-controlled to be able to adjust the grinding speed and transport speed that is required and most suitable for the material.
- Exact grinding wheel adjustment by a specially developed laser measuring system. This system measures and pre-defines the free distance between the grinding heads Therefore, it is not necessary to even out the grinding heads with measuring devices after the grinding process Even when the grinding heads are left separated after an emergency stop of the machine, they will return to their exact position when the machine is restarted. The transport equipment only starts after the grinding heads are repositioned. The bricks left near the grinding heads are not affected and show no dimensional tolerances.
- A specially developed transport system forwards the bricks on V-belt transport belts through the grinding installation, thus offering large benefits regarding wear and operational safety. The V-belt guide secures the lower transport belt against lateral shifting. The exterior belt surfaces are supported by sliding guides to ensure safe forwarding and stopping of the bricks.
- Adjusting belts in the feed zone of the grinding machine run with a lever-operated synchronous drive system to provide for an exact adjustment to the grinding centre axis
- Positioning of the individual grinding heads with free-from-play servo drives to guarantee an exact stopping point and a precise readjustment of the grinding heads.
- Special suction conduits to remove the grinding dust, with a waste box for possibly larger chunks of waste material that are then ejected separately.
- Drive motors for the grinding bodies with extra stable and protected bearing.
- For safe operation of the machine it is necessary to have a solid foundation which is ensured by the entirely welded structure and the milled and treated surfaces of the base frame.