technical NOTES

S. N. SALIENT FEATURES ROLLER PRESS VRM

8 Power demand Power demand in roller

press system is less hence

will result to less contract

demand.

Power demand in vertical

roller mill system is more

hence it will lead to more

contract demand

9 Loss of production due

to worn out parts

there is no loss of

production throughout the

life of rollers

Loss of production is

approx.

10 ton or 5% of rated

output as the wear and

tear of the rollers increases

hence the average

production will be lower.

But Recently Sinter cast

rollers which has less wear

and 1 year life are being

incorporated

10 Yearly maintenance

cost for clinker

grinding

Maintenance cost is

almost negligible since

no welding of rollers is

required.

Maintenance cost is

higher due to re-welding

of rollers after every

1000/2000 hours.

11 Erection time

requirement

4 months 7 months

S. N. Particular VRM Grinding

Semi-Finish

Grinding (RP +

Ball Mill)

Finish Grinding

(RP)

(^1) Design Compact Complex Compact
(^2) Circuit Simplicity More Less More
(^3) Grinding Process Compression &
Shear
Compression, Im-
pact & Attrition
Compression &
Shear
4
Moisture
Suitable for
Slightly high
moisture
Suitable up to 4%
feed moisture
Suitable up to 4%
feed moisture
(^5) Hot Air requirement High Low Medium
(^6) Power Consumption High High Low
(^7) Product Quality Better Best Better
8
Initial Equipment Cost Moderate High
Low (in case of
less capacity)
Very High (in
case of higher
capacity)