PTO ?

[logan97]

The plastic cover around the PTO came with a chain. What exactly is it's function ? The plastic does spin when the PTO is engaged.

 

[whistlepig]

The chain is supposed to keep the plastic cover from spinning. A spinning plastic cover on a PTO shaft is about the most dangerous thing there is on operating an implement on a tractor.

 

[SARG]

I assume you're talking about the PTO drive shaft. The chain is usually provided to hold or hang the loose end from the equipment when it is not attached to the tractor. You would wrap or attach one end around where the top 3 point link hooks to the implement ( brush cutter etc) and the other around the end of the pto shaft to keep it up.

I have seen some youtube clips where the chains are hooked from the top link to the pto covers while the shaft is spinning on the tractor.

 

[Duffster]

A spinning plastic cover on a PTO shaft is about the most dangerous thing there is on operating an implement on a tractor.

Why is that?

 

[SARG]

Check the end of this video. It shows the proper chain usage.

YouTube - How to Measure and Cut a Tractor PTO Shaft

 

[Transit]

The plastic cover around the PTO came with a chain. What exactly is it's function ? The plastic does spin when the PTO is engaged.

The answers are half right. The plastic tube is a safety shield with cups at both ends to protect you from coming into contact with the rotating steel shaft and the U-joints at both ends of the drive. The chain on the PTO drive end keeps the shield from spinning and the safety cup in place over the U-joint. If the driven end of the shaft were ever to be uncoupled from the PTO drive, the chain would keep that end of the shaft from swinging about wildly.

At the implement end of the shaft, the chain and the cup do the same, keep you from contacting the steel shaft and U-joint. If the shear bolt were to brake, the chain keeps that end from swing around wildly. Remember, we are talking about a shaft that spins at 540, 750 or 1,000 rpm. You do not want to get warped up in the works. :thumbsup:

 

[SARG]

Your comment also appears half right. PTO shafts are designed such that when the shear bolt does "break" .... the union just spins with no chance of the shaft "flopping around".

 

[Transit]

Your comment also appears half right. PTO shafts are designed such that when the shear bolt does "break" .... the union just spins with no chance of the shaft "flopping around".

No, with the shear bolt broken there is nothing to keep the U-joint from spinning and working itself off the implement drive shaft. Maybe it does not happen too often but you don't want to find out the hard way, or do you?

 

[whistlepig]

The plastic safety shield on the PTO should always be fixed and not spinning. This prevents loose clothing from getting caught on the PTO shaft and the operator being tangled up in the PTO shaft.

 

[SARG]

No, with the shear bolt broken there is nothing to keep the U-joint from spinning and working itself off the implement drive shaft. Maybe it does not happen too often but you don't want to find out the hard way, or do you?

I suspect that's why there are "locks" on both ends of the shaft.

 

[Transit]

The plastic safety shield on the PTO should always be fixed and not spinning. This prevents loose clothing from getting caught on the PTO shaft and the operator being tangled up in the PTO shaft.

Dead on!

 

[banjodunn]

G'day over here now the plastic covers come with no chains the theory behind that is that the cover can turn with the shaft but must stop when you put your hand on it, this save the plastic bushes that the cover mounts to from wearing out. In reply to some of the other answers the chain is not there to hold the end of the pto up off the ground as this can deform the cover and/or the bushes and prevent it from spinning freely


Jon

 

[whistlepig]

G'day over here now the plastic covers come with no chains the theory behind that is that the cover can turn with the shaft but must stop when you put your hand on it, this save the plastic bushes that the cover mounts to from wearing out. In reply to some of the other answers the chain is not there to hold the end of the pto up off the ground as this can deform the cover and/or the bushes and prevent it from spinning freely


Jon

Perhaps its just because that I'm old and mouldy but an opportunity to talk to someone in the land of OZ is just pretty darn neat to me. The theory of the plastic shield spinning freely to save wear on the plastic bushings makes very good sense. But if the plastic shield isn't rotating freely you would not know it until your jacket, along with you, got wrapped around the PTO shaft. I would rather have the chain holding the PTO cover stationary. That way If the safety PTO cover failed it would break the chain and you would know from the tractor seat that is was defective. I have been brush hogging with chained PTO safety covers for over 25 years and have never had one fail.

 

[aczlan]

No, with the shear bolt broken there is nothing to keep the U-joint from spinning and working itself off the implement drive shaft. Maybe it does not happen too often but you don't want to find out the hard way, or do you?

Every piece of equipment that I have used with a shear pin (2 bush hogs. a tiller and a baler) have had a retainer clip to keep the PTO shaft from coming loose when the shear pin breaks.


Aaron Z

 

[shiver]

Why is that?

YouTube - The dangers of an unguarded PTO shaft

Now, imagine being found by your wife or children....

 

[blueriver]

the theory behind that is that the cover can turn with the shaft but must stop when you put your hand on it
Jon

No way would I even attempt to test this theory ... people do not put anything on or near a turning PTO.

I believe the chains serve a purpose ... the tracor end I always atatch to the drawbar and the implement end to the implement.

I do agree not to hang the stored shaft from this chain.