Service life testing

PUCEST® system impact elements

Application: Impact swing arm at chute inlet in drum separator

1. general:
The Styrian Ore Mountain is the largest open pit ore mine in Central Europe and the largest siderite deposit in the world. The value mineral is a carbonate iron ore. The rocks of the deposit can be roughly described as, porphyroid as the geological bedrock, ore bearing formation, limestone and shale.

In the course of the preparation process, crushed material runs over a central chute inlet into a drum separator. The inclination of the inlet chute is ≥ 30°. The material is edge grain, grain size from 30-130 mm. The flow velocity is about 3 m/s. The quantity is about 250t/h.

The production cycle runs 24 h a day for 10 days each with subsequent revision shutdown for 2 days.

3. problem definition:
To protect the separator drum from wear, a material brake was provided at the chute inlet. The material brake was first designed as a chain curtain, after which impact bars made of solid manganese high-carbon steel were used. Both variants showed extremely high wear and only service lives of 2-3 weeks.

3.1 Wear stress:
Impact wear occurs on the material brake. The material of the material brake must absorb the impact energy on impact as well as the abrasion when the material slides off.

3.2 Solutions:
Due to the stresses involved, hard materials, metallic or ceramic, are not suitable or are only suitable to a limited extent. The use of tough manganese hard steel (chain curtain, solid beams) delivered only unsatisfactory service lives. The good experience of VA- Erzberg GmbH with the material PUCEST® in impact wear should also provide a remedy there.

For this purpose, Ing. Wedorn proposed and implemented the use of PUCEST® System impact beams with modular blocks made of PUCEST® and composite blocks PUCEST® + carbide.
The strong impact wear is absorbed on the one hand by the damping properties of the PUCEST® 65° Shore material and on the other hand by the highly wear resistant carbide.

The blocks are mounted on a rail and can thus be quickly exchanged or flexibly arranged.

4. service life:
The PUCEST® System impact beams with their individual blocks were mounted on the impact rocker bars in the customer’s own workshop. In week 01/2016, the preparation plant was started with the production cycle described above. No abnormalities could be detected during the respective shutdowns.

During the inspection on 20.05.2016 together with Mr. Ing. Wedorn the following could be determined:

Center of main impact area:
Composite blocks PUCEST® + carbide, s = 50 mm
= NO wear detectable,
no spalling, can still be used!

Block PUCEST® 65° Shore, s = 50 mm
approx. 50% wear, can be used further!

5. summary:
The blocks of the PUCEST® impact beam not only resist impact wear and are characterized by an extreme improvement in service life, but are also light and easy to install. This is an important aspect, especially when access is limited, as in this case with the separator drum.

Sources: VA- Erzberg GmbH (geology)
Pucest Protect GmbH (product images)
Photos: Ing.Wedorn