KLEEMANN Crushing tools for impact crushers

Crushing tools for impact crushers

KLEEMANN impact crushers can be used for a wide range of applications. From classical processing of natural stone and the recycling of high volumes of building rubble to quarrying and mining applications – the focus is always on two particular challenges: increasing utilization rates and lowering operating costs. The crushing tools are subject to varying degrees of wear depending on various influencing factors.

Genuine KLEEMANN blow bars offer much more than just the right sizes. The materials used, alloying elements and the entire casting process are important foundations for a reliable crushing tool. KLEEMANN impact crushers can be used for a wide range of applications. From classical processing of natural stone and the recycling of high volumes of building rubble to quarrying and mining applications – the focus is always on two particular challenges: Increasing the service life of blow bars and lowering operating costs.

The cost-effective usage of blow bars is influenced by a number of factors. e.g. the feed material, rotor speed, moisture content, feed size and the crushing ratio. Determine the ideal blow bar for your specific application with the aid of the following points. Access a choice of various different blow bars and begin your crushing project with economically optimised crushing tools.

The correct assessment of blow bar wear is a prerequisite for the cost-effective operation of an impact crushing plant. Replacing blow bars at the right time guarantees successful operations and significantly reduces operating costs. It is common for blow bars not to wear evenly across their full width. The wear limit is reached when the specified minimum wear dimension is no longer fulfilled at any one point on the blow bar.

Please note that changing the blow bars too late will lead to increased wear on the rotor and the blow bar mountings. The consequences of this are costly subsequent damage and prolonged machine downtimes. Apart from the necessary renewal of the rotor armouring (hard facing), the clamping wedges for blow bar mounting are frequently also damaged.

• For preliminary cleaning of the crushing chamber, it is recommended to fill the crusher with clean, coarse material for several minutes.
• Installation and removal of blow bars must always be carried out by a minimum of two persons.
• Always use suitable lifting gear and tackle.
• Completely extend the crusher gap before installing new blow bars to ensure that replacement in order to avoid a collision between the blow bars and the toggle after installation.
• Improper replacement of blow bars can lead to serious damage to the crusher.
• Operate the rotor only when the blow bars have been correctly installed.
• Always replace blow bars one after another.
• Replace all blow bars even if only one of them is broken.
• Before making final adjustments, briefly run the machine at its highest rotational speed (for the EVO 1800 rpm), then check the wedge clamps and, if necessary, tighten any loose bolts and screws.
• Always use conical spring washers with the clamping bolts of tensioning devices. Re-tighten the clamping bolts after approx, two operating hours.
• Caution: An unsecured rotor can lead to serious injuries. Therefore: Always observe safety regulations and instructions!

A detailed description of how to replace blow bars can be found in the instruction manual for the respective machine.

In addition to their shape, the blow bars benefit from the properties of their respective components:

• The chamfering of the impact edge, aligned to the rotor's rotational direction, ensure longer crushing effectiveness and better crushing performance for a prolonged period of time.
• The holes on the side ensure easy and quick handling when turning or exchanging the blow bar.
• The lug on the back assures ideal transfer of the centrifugal forces to the rotor (C-shape only).
• The clamping wedges fix the blow bars in position and ensure that they rest correctly on the contact surfaces of the rotor. The machined clamping surface provides a precise fit over the entire length with a reduced risk of breakage.

Depending on the crusher size and application, KLEEMANN impact crushers are fitted with one of a selection of different rotors. The number of blow bars installed depends primarily on the crushing chamber geometry and its corresponding intake behaviour. In the case of smaller crushing chamber geometries (< 1100 mm intake width and a rotor diameter of < 1100 mm), rotors with two or three blow bars are used. Larger crushing chamber geometries (over 1,200 mm with larger rotor diameters > 1,200 mm) are equipped with rotors featuring four blow bars to increase the operational spectrum. In the majority of applications, these rotors are operated with two high blow bars and two low blow bars.

In practice, different materials for manufacturing blow bars have become established standards. These include manganese steels, steels with martensitic structure (referred to in the following as martensitic steels), chrome steels and Metal Matrix Composites with ceramics (MMCs), in which the various types of steel are combined with special ceramics.

An increase in the steel's wear resistance (hardness) is generally accompanied by a reduction in the impact resistance or load bearing capacity of the material. In order to simultaneously ensure optimal utilisation rates and low risks of breakage, the appropriate blow bars must be selected according to the material to be crushed, the non-crushable content and the feed size.