Cement Raw  Vertical Mill Area Maintenance

Dam Ring

There is high wear and deformation in the dam ring segments.

Recommendation:

Replace the dam ring segments with a new one.

Action has been taken:

The defected dam ring has been replaced.

Thermo cable for rollers bearings

The thermo cable for rollers bearings which indicate the temperature of the bearing is not
working.

Recommendation:

We recommend repairing this thermo cable and connecting it with the CCR, where it is very
important indication for bearing statues inside the roller assembly to prevent any suddenly
damage for this bearing.

Action has been taken:

All thermo cables have been repaired and the bearings temp for all rollers appears at Control
panel.

 Tire Bolts For R.M Rollers

The tire bolts is loose also the bolts and its nuts have a sever wear, and the protection cups for all
bolts in the rollers have a severe wear too.

Recommendation:

1- Replace the worn out tires bolts.
2- Replace all protection cups with a new one and the cup design should be changed.

Action has been taken:

Only the new cup has been fabricated with the same old material and design but it have not been
erected.

Roller housing for Vertical Raw Mill .

The rollers housing and bolts at the side of hot gas inlet is subjected to high wear, and this is will
force you to replace the roller housing.

Recommendation:

We recommend fabricating a protection cone around the roller casing from voted to protect the
roller casing and bolts from wear (this is an additional solution).

Action has been taken: No Action has been taken.

 The lock plate for R.M roller bearing inner race on the shaft

All bolts of lock plate for bearing inner race on the shaft are very loose.

Recommendation:

1- We recommend to retighten the bolts of lock plate with its specified torque
which is 1400N.M
2- Weld a steel bar between every 2 bolts to prevent this bolts to be loose
again (this matter is highly recommend).

Action has been taken:

The bolts of the lock plate for bearing inner race on the shaft have been re-tighten
with torque 1000 N.M only.
Note: No steel bars have been welded between bolts, so it will cause the bolts to
be loose again.

  Rollers bearings

1- There were metal ships inside the rollers with a big amount and size.

2- The outer race of the 1st bearing in all rollers has pitting and there is wear in the cage too.

3- The housing of the rollers bearings full with contamination.

Recommendation:

1- Replace the bearings of all rollers due to metal ships existence on the roller housing and pitting on the outer race which is very clear, also they should be replaced according to their life time.

2- The oil must be replaced and the oil tank and roller housing must be cleaned very well.

Action has been taken:

  The oil has been replaced and the oil tank and roller housing for all rollers have been cleaned.

 Rollers grinding parts

Recommendation:

Fabricate a template for measuring the wear rate of R.M grinding parts

Action has been taken:

The template for roller tire has been fabricated and the tires wear have been measured to be 110 mm (As approach measurement) from 170 mm as original thickness.

  R.M Reject cone

1- The reject cone metal sheet has worn out on its circumference.

2- The reject cone supporting webs must be checked for cracks and loose bolts.

Recommendation:

1- Replace the worn out sheet metal with a rolled sheet metal.

2- Re-weld the supporting web for the reject cone and re-support it well.

Action has been taken:

1- Only the worn out sheet metal has been patched.

2- The supporting webs have been supported well and repaired.

3- Reject cone with its webs have been repaired

  Raw mill scraper

1- The wear plate and base plate for the scraper have high deformation.

2- There are some missed wear plates.

3- There are 2 lining plates in the scraper platform have been deformed due to looseness bolts.

Recommendation:

1- Remove the 2 defected lining plates for scraper platform.

2- Replace the defected wear plate and erect the missed ones.

3- Re-tighten the fixation bolts of the scraper bottom  linings to avoid contact with the movable scraper’s blades.

4- Maintain  gap  between   scraper’s  movable  blades  and  scraper  stationary bottom linings not less than 30.0 mm

Action has been taken:

   The two defected lining plates for scraper have been repaired

  Hot gas nozzles

1- There is worn out in the guide vanes.

2- The flange of the hot gas nozzles is not supported correctly.

Recommendation:

1- Replace the worn out guide vanes with hardox steel

2- Re-adjust the position of the hot gas flange due to bad supporting.

3- Blind guides  vanes (under the  rollers  hub housing) direction  to decrease  wear occurrence. (Already done)

Action has been taken:

   The worn out guide vanes have been repaired with ST 37

Vertical Raw mill  armor ring

There are many deformed and worn out armor rings.

Recommendation:

Replace the deformed and worn out armor rings.

Action has been taken:

No action has been taken.

  Cement Raw mill Spring rod

1- There is no expansion joint which protect  the piston rod from scratches by the  material which causes repeated damage  for the  seal kit of the  piston head.

2- The repair kit for the piston head of roller no.2is defected  and there  is oil

leakage.

Recommendation:

Erect an expansion joint for all pistons rods.

Action has been taken

No action has been taken.

 Cement Raw mill  rocker arm of rollers

There is a sever wear in the rocker arm at the position of the spring rod pin.

Recommendation:

Replace or Repair the worn out part in the rocker arm to avoid any failure damage for roller cylinders or spring rod bearing.

Action has been taken:

No action has been taken.

in the next post I will talk about raw Mill Separator and bucket Elevator and other rawmill are Equipment

if you have any question don’t Hesitate to contact me at project20062015@gmail.com