Edgar arinaitwe

Supervised by kakama Gilbert, Maintenance Engineer

1

Report for Mechanical maintenance of the entry support hearth roll (E.S.H.R) and

the Turn down roll (T.D.R) bearings. by Edgar arinaitwe 29th may 2014

Due to the 20th may 2014 shutdown, mechanical maintenance work has been done work to work with different

technicians and their respective supervisors/shift in charge. Under kakama Gilbertl,I cleaned filters for power

packs, worked on all hearth rolls removed old grease, check the condition of the bearing and put new grease

among other jobs, I was allocated to remove the old grease in the entry support hearth roll and the turn down

roll bearings too.

As usual cleaning first and preparing the entire area to give me a motivation to work perfectly up to the end of

work, opened the support roll and the turn down roll bearing covers on the other hand.

(A) Opening entry Support hearth roll (B) opening the turn down roll bearing

Obviously the grease inside the bearings was used up, old and dirty as expected earlier before.

(C) The dirty grease in the bearings after opening

Edgar arinaitwe

Supervised by kakama Gilbert, Maintenance Engineer

2

So we had to clean the bearings so neat to inspect the mechanical conditions of the bearings.

(D) Turn down bearing after cleaning (E) entry support hearth roll after cleaning

After cleaning I inspected the conditions of the bearings.

For the E.S.H.R the bearings were ok but to the T.D.R the bearing collets lock were all loose open on the drive

side. They are suspected to have loosened due to the consistent rotation of the roll.

(F) Loose collets in turn down roll bearing coupling (H) loose set screw on the collets lock

The collets lock is supposed to be with three set screws but to my view I found that one set screw was missing I

tried to check around the coupling it was not in there meaning that it was not put in there at times of

assembling. This set screw m10 by 15mm is too missing in the stores after me inquiring from them.

Edgar arinaitwe

Supervised by kakama Gilbert, Maintenance Engineer

3

(I) The missing set screw thread hole.

after cofirming the bearings to be ok in all the bearing couplings, I replaced the collets in their right positions.

though the missing set screw may be the great factor behind the incidence of loosening the whole set of the

collets. I firmly tightened the two set screws to their full torque.

(J) Re-tightenning the set screws (K) fully tightennig the set screws

and greased all the bearings on all sides of the furnace/line E.S.H.R and the T.D.R respectively.

Edgar arinaitwe

Supervised by kakama Gilbert, Maintenance Engineer

4

(L) GreasIng the E.S.H.R (M) greased the turn T.D.R

After greasuing (L) and (M). The coupling cover were replaced after properly organizing the gaskets.

Before closing the turn down roll bearing and coupling covers. there is a lot of grease in the turn down roll

coupling. I applied the white solventless non-gass liquid silicon on the cover gaskets both on the drive and

operators sides to stop all grease leakages on the coupling. instructed by Mr. kimura. ( Japannese expartriate) as

shown in pictures (N) & (O).

(N) applied silicon on the coupling covers (O)

Opened off the greasing allen bolts on the covers and put back the covers. the excess grease is pressurized out

when re-tightening back the coupling covers on the T.D.R as shown below.

Edgar arinaitwe

Supervised by kakama Gilbert, Maintenance Engineer

5

(P) Opening the greasing Allen bolts (Q) excess grease coming out of coupling on re-tightening.

(R) finished coupling of the T.D.R (S) finished coupling of E.S.H.R

After all has been done as explained all from the start of this report, I cleaned the couplings (R) and (S), re-

tightened them to their full bolt torque and finished the duty in only 8hrs of my 29th may 2014 daily shift duty.

In conclusion we immediately need to purchase the set screw missing in the turn down roll collets for at

any time we have another shut down we replace the missing screw otherwise after a long run of the line the

screw will loosen quickly enter the bearing rollers and destroy them so becoming costly to replace the bearing.

This was like the only big problem found in the whole work. Greasing is supposed to go on as usual to maintain a

good condition of the bearings.

Well thank you very much