NH 630 round baler breaking a chain

[Chuck_Lind]

I have a NH 630 round baler that keeps breaking a chain on the pivot roll (the top most roller on the baler). The pivot roller spins freely with the chain off, so I don't think it's a bearing.

When I create the bale core, the chain snaps.

Does anyone have an inkling as to what the problem might be.

Thank you in advance...CL

 

[Mith]

Get someone to look at the shaft that the toller is on at the sprocket end and spin the roller. See if the shaft is eccentric. Sounds like a bent shaft as it rotates tightens the chain and snaps it. Also you could put a new chain on and see if it goes tight at a particualr point indicating something is eccentric.
If this is not the case a possible fix would be to get a longer chain and use spring tentioned idler sprockets to keep it tight but also allow it to flex.
Also cheack to see if the chain is running straight and not bending.

Hope this helps

 

[Chuck_Lind]

Thank you, Mith, for the suggestions.

However, I did run the baler with the side cover off to ensure that what you described is not happening. The roller turns freely, no eccentric or anything like that.

My feeling is...the roller is binding somewhere when the bale is being formed. For a chain of that size (RC 50) to break indicates a real source of stress.

I'm waiting for one of the experts to show up and locate the problem.

Thank you again..Chuck

 

[Chuck_Lind]

Received a call from the dealer repairman today...here's the scoop on the chain breaking:

1. The bearings were completely worn out on both the top roller and the bottom roller.

2. The top roller shaft was bent as a result of the bearing being worn so badly.

This baler is a 1991, so it's no surprise the bearings went bad after years of use.