Refurbished Steel Balls
Refurbished Steel Balls
A cost effective and alternative choice to new steel balls material. However, it still carries a comprehensive guarantees as with the new grinding media.
As part of good operational practice, ball mill regularly re-grade chamber charges to remove rubbish and under-size grinding media. The cleaned and graded charge is then returned to the ball mill together with top-up grinding media to return the ball mill to its most efficient operating condition.
This is perfectly acceptable because the Cast High Chrome Grinding Media used in modern grinding media charges is through-hard, i.e. the hardness towards the center of a grinding media is the same as the initial surface hardness. It also means that this type of grinding media retains its shape for the majority of its useful life.
Benefits of Refurbished Steel Balls
Cost Saving – Price for refurbished steel ball is up to 20% cheaper than new chrome grinding media.
Guarantee – With the ‘through-hard’ characteristic result, we are able to offer the same wear rate and breakage guarantee as for new grinding media.
Quality Assurance – All 1st ball mill chamber grinding media is hand-sorted and all miss-shapes and true rubbish are removed before grading. The 2nd ball mill chamber grinding media have obvious rubbish removed and smaller sizes are mechanically screened to give nominal size grading.
Performance Guarantee in Ball Mill
The total steel ball wear rate will not exceed 35 grams per tonne of product ground for OPC using 100% clinker. This wear rate to be established over a period of two years or 10,000 operating hours, whichever is the shorter, in the event of failure to meet the guarantee, compensation to be evaluated on the basis of grinding media used in excess of the guaranteed figure relative to the appropriate quantity of product ground as determined by the following formula:
C= (WA – WG) x T / 10(factor of 6)
C = compensation in tonnes of replacement media (FOB value)
WA = wear rate achieved
WG = wear rate guaranteed (grams/tonne)
T = throughput in tonnes
10(factor of 6) = factor to convert wear rate expressed in grams to tonnes
Performance Guarantee Condition in Ball Mill
- Normal ball mill operating conditions are maintained.
- No operation without product.
- Maximum steel ball size to be 90mm diameter in 1st chamber and 50mm in 2nd chamber.
- Minimum volume loading to be 28%.
- Any compensation claims must be proved to be as a result of casting integrity.
- All relevant mill data to be made available free of charge in event of any compensation claim.
- Any compensation claim to be settled with supplies of future casting or grinding media requirements.