Repair and overhaul of RABA and KAROSA front axles
RABA and KAROSA front axles are repaired and overhauled using top quality machinery and equipment as an additional programme to our production. We use our experience from our own development and manufacturing of front axles, knowledge from Karosa and technical information from operators. We regularly carry out further construction modifications and technical improvements tor higher quality product with higher utility properties for the satisfaction of our users.
Course of repair and overhaul of an axle:
- all repairs, renovation and manufacturing of new parts are done using the same, single-purpose machinery equipment as used in the standard series production of axles with the use of the maintained technical documentation,
- after receipt of the axle for repair and the documentation, the axle is completely washed by the steam developer, followed by the gradual dismantling and removal of the semi-axle pivot pins and the ball pins on the arms, then there is blasting of the pitman, brake jaws, cover metal sheets and some minor parts, as well as the washing of the wheel heads and rotary pins,
- for brake jaws, after removing of rivets from the old lining, the pockets are calibrated if required, are replaced and the Ferodo mixture 2020 lining approved by Karosa is applied with added thickness, which is consequently turned to the dimension of the diameter of the drum,
- measuring and turning the wheel head prevents any brake drum ovality, asymmetry of the braking effect on the left and the right side and any other defects,
- the brake cylinders are renewed based on the exchange of rubber piston collar, boots and sealing, caps with blowing are fitted and in the case of damage, the cylinder body is changed,
- conical bearings in the wheel heads are inspected after washing and replaced where necessary
- all wheel bolts are calibrated, damaged bolts are calibrated and can also be replaced with new bolts – manufactured by us,
- all sealing elements (git seals, rings and collars) are automatically replaced with new elements,
- re-assembly is done on presses and in specialized workplaces, similar to the series axles by the same qualified mechanics. The same technological procedures and drawing documentation are used. An identification number is assigned to each axle while a mark and rehabilitation sheet is issued into which all operations, consumable parts, measured values of required clearances and pre-stressing , tightening moments, run-out of drums, SBS rings, etc. are recorded. Axles are fully lubricated with La2 grease. For Raba front axles, there is also the reconstruction of the lubrication of the knuckle pin with independent lubrication of the axial bearing and new sealing on the cross pin pockets which leads to a significant prolongation of the service life of these axles,
- after assembly, testing of all functions and the final inspection, the axle is sprayed with Feidal PG53 base paint and after drying with black-grey Feidal KD25 top coat paint and then the axle is sent for dispatching,
To permanently increase the quality and utility properties of the product, we regularly inspect the axles generated by other repair shops. Defects which are found on these axles result in product failure from the very beginning. Under pressure to keep low prices for overhaul and repairs of axles, these companies use pseudo-renowned spare parts, parts from unauthorized manufacturers that misuse our drawing documentation and do not follow any changes. When welding pins, suppressing brake drums, these companies use unoriginal pockets, rivet brake lining of an unknown nature and unacceptable rivets and technologies. They easily re-attach the used sealing and cannot manage the worn holes in the rotary pin for placement of the pivot pin and attach them with a clearance. They do cannot grind ball pins while the surface treatment prevents long-term use of the product.
Low-quality repaired axles, even at a low price, in the final evaluation will be more expensive due to the cost of frequent replacement.