Best method to press bearings onto the rollers

[nothernlights]

When we get a new set rollers it comes to us without the spacers and bearings attached. What's the best way to press the bearings onto the rollers?

Thanks.

 

[Paultheprinter]

Hi there,

im not sure the name of the tool but is looks like a box section cut diagonaly in half to give two sides and a top, its about 12 inches long and keeps the bearing square when you tap it onto the stocks. Every printer i have worked for has a couple of examples rusting in most corners. (i know them as bearer tappers)

Paul

 

[CKL]

Bearings

Bearings

I use a small mini sledge hammer. You need to hit them square. It takes a little experience. Newbies I have use wood, instead of just hitting the bearing.

 

[prepmaster]

I would disregard CKL's reply completely. Hitting the bearing will damage the race. Bearings are precision built with very tight tolerances. Installation should be performed using a hydraulic or other mechanical press with pressure applied to only the inner part of the bearing. Lubricate the shaft of the roller and the bearing before continuing with the installation. Hitting the bearing will shorten its life by more than half and will cause minute movements in the way the roller will spin maybe causing uneven printing specially light screens. Take it to a machine shop if you don't have the right tools.

 

[John Kay]

Roller bearings

Roller bearings

The correct way to install bearings is to use an "ARBOR PRESS" Since most pressrooms do not have one most roller companies supply the rollers "Press Ready" Another important consideration is the bearing manufacurer. It is imperitive that a high quility bearing is installed, SKF is my personel choice. Be carful of your local supplier offering "Off Shore" bearings, this is often a code word for cheap inferior bearings.

John

 

[CKL]

Bearings

Bearings

True, using a hammer is NOT the best method. I would love to work with all the right tools and adequate time to do so. The facts are some large sheetfed shops are under tooled and under staffed. At 2 :00 A.M. corners are sometimes cut.

All rollers should come with bearings press ready. The only bearings not installed are meter & water forms due to the gears not being attached.

 

[cjwworld]

True, using a hammer is NOT the best method. I would love to work with all the right tools and adequate time to do so. The facts are some large sheetfed shops are under tooled and under staffed. At 2 :00 A.M. corners are sometimes cut.

All rollers should come with bearings press ready. The only bearings not installed are meter & water forms due to the gears not being attached.

Most Roller Vendors will have option to have the bearing pressed in before shipping, (If you ask)

 

[nothernlights]

Thanks. I'll double check with to see if my supplier can do that for me. My only concern is that they may sometimes loose spacers or bearings if they are already attached to the roller when we send them to have the roller recovered ( this had happened before ).

But in cases where we need to install it what tools are needed to install them properly? An arbor press?

 

[Al Ferrari]

Can you please recommend a source for an Arbor Press adequate for installing bearings on rollers from a 40 inch press, say 50 inch overall shaft length?

Al

 

[prepmaster]

I still think that a machine shop is the best way to go.

 

[qaos]

The bearings are placed with hammer and parts having contact with the internal and external ring at the same time to avoid hitting the balls. After hitting with the hammer until set point. If the bearing is very tight or very loose, should correct the diameter of the shaft.

 

[prepmaster]

I still say NO to hammering the bearing no matter what even If it is 3 am. I would wait for a machine shop to do the job properly. What's the use if you put the bearings in wrong and ruin the roller in the process. Not to mention the ruined jobs and angry customers. By the way I was in the auto repair business for over 10 years before getting into prepress and printing. I know what it takes to press bearings. Take my word for it or find out for yourself if I was right or not.

 

[Sam Ybarra]

Hitting them on with a hammer and brass drift is one way to do it...Hitting the inner race of the bearing will not cause damage if done right...
If the end of the roller is threaded you could use a socket head bolt with a very thick washer and basically bolt it on...
A press would be the best way to mount the bearings but depending on the width of the roller one would be looking at a very big press...
If your roller supplier can or do mount the bearings for you why not ask them how they do it...My money is on "They use the hammer method"...

 

[jbeniston]

If you have to do it without all the right equipment etc, It's not easy to find a machine shop at 2a.m. You can find a piece of tubing with as close to the diameter of the INNER race. Slide over the journal end and make contact with the inner race and tap the other end of the tube with a heavy hammer. This is not the best method but at least it will get the job done without damaging the bearing.
You could also use a pin punch against the inner race, but you will have to be very careful that it doesn't slip off and punture the sealing ring.

 

[Sfdp2300]

Get peice of aluminum or hard plastic have your shop bore out the core to fit over your roller journal make sure the body of the material beeing use covers the bearings innerace and outer flush. Center your bearing over the journal and tap on with a hammer (plastic mallet). But it nicer when the rollers come in press ready.... I have had to deal with both..

 

[dancingfox]

I would disregard CKL's reply completely. Hitting the bearing will damage the race. Bearings are precision built with very tight tolerances. Installation should be performed using a hydraulic or other mechanical press with pressure applied to only the inner part of the bearing. Lubricate the shaft of the roller and the bearing before continuing with the installation. Hitting the bearing will shorten its life by more than half and will cause minute movements in the way the roller will spin maybe causing uneven printing specially light screens. Take it to a machine shop if you don't have the right tools.

Yes, SKF is by far the best I've seen. We're currently testing a non-greese bearing from Peer manufactured in Thailand. SKF just recently acquired Peer. For our "BE" presses.

We use a bearing puller and re-use most of our SKF bearings as they rarely fail and burn up the journals.
We purchase our rollers from a few key suppliers that will include the J/R (if needed), bearing, and recover as one price or as line item charges. Based on plant needs.

If doing this yourself at a machine shop or in house remember to fill the bearing back up with greese using a small syringe (can't remember the name of ours).

Lastly, when working with the rollers, a dry ice machine is great at taking the ink, water waste, wash, and other chemistries right off the roller.