Kuhn Hammer loosing power

[eddie]

Hey guys
If anyone knows or has had this problem solved with a kuhn or another off brand air hammer, I would appreciate any help with resolving this problem.

[imagedude]

Is it still running at the usual BPM? Slipping drive belts is a common maintenance issue on some of the Kuhn clones.

[eddie]

The problem is the air capacity that delivers the power of the blow has decreased. Apparently there is a valve,seal, or somewhere that the air is by passing

[John N]

Ive never worked on a Khun, But checking the ram & compressing piston pistons rings would be a good starting point, as well as any packings in the stuffing box (gland where the ram exists the cylinder).

These are the usual points of air loss.

[bbehnke]

I have experienced the same problem with my "off brand" Kuhn hammer and it was the belt that was slipping. I think that I would check this first to see if that improves performance.

[Hofi]

first of all check if the hammewr is working in its natueral ryhthem 220- 240 bpm
if less then 220 the belts are slipping tighten them or if worn out change them!
if the belt are ok and the hammer is in the right ryhthem (the check is done when u forge a piece of hard wood and not on idle) check while the hammer is working if u have full recovery means if the day light is acc to the book -i think 91/2'' if very much less and there is no full recovery it means the hammer piston is loosing air on the way up and when it is not going all the way up on the way dowen the hammer is not having full valocity and no power-then check the amount of air that is leacking around the silling collar by putting your hand there --be carefull-- if there is a bIg leakeage u have to repair the silling system and get the right parts from the agent.
this happens when not enough oil is oiling the ram allways more oil is better then less .on the kuhn hammer the oil is been SUPLIED with possitive pump and many times the oil suply to the hammer is lesser do increase the oil amount u have instructions in the book. if all this is ok there are two more things to do 1. on the kuhn the unit is a close box the air is going and coming IN AND OUT through a filter if jamm u have a problam of a insuffitient air coming into the hammer and the out let of air is not free!! cleen the filter.
2 if u take the cover away under the cover there is an adjustable left right rode see if on nutral the marks mech if not adjust it again acc to the book.
there are some more things but it is complicate for me to explain on the mail.
hope i helped u some
HOFI

[Ian Wille]

I'm attending SIU in Carbondale, and we have one of the new model 50 Kg Kuhn hammers. It's been out of commission for the past three or four years due to the fact that it was losing power, and the rhythm was slowing down. It was losing power to the point that while running, the ram would just stop cycling and sit on the bottom die. It also knocked loudly while running, something that was not coming from slipping belts. All of these problems got worse as the hammer was used. When I finally looked into it (and I was the 4th guy to do so), I noticed that the rod was loose in its bushings on the compressor cylinder (the source of the knocking).

That prompted me to take apart the rear (compressor) cylinder to check on the piston rings. Upon taking the cylinder apart, my first surprise was that everything was bone dry and covered with a black powder mixed with specks of metal. My next (horrible) discovery was that the rings had entirely disintegrated, and that both the piston and cylinder tube had been heavily galled, which was where all those shiny little specks of metal had come from. It looked as though someone had taken a chisel and incised the entire circumference with rather heavy grooves.

Now from what I can tell, there was never an oil line that ran to the compressor cylinder. The only oil line on it goes to the ram cylinder. The dealer at Centaur Forge that I've been dealing with says that the rear (compressor) cylinder does not require any oil due to the materials the rings are made of. Note that this cylinder is an aftermarket component that Kuhn buys ready to go from another manufacturer. However, it seems that a lack of lubrication in the cylinder was the source of the failure. Nevertheless, we are awaiting the arrival of a brand new compressor cylinder to get the hammer back up and running. Once its installed, we are thinking about running an oil line to the compressor cylinder to keep this problem from happening again.

Your hammer may very well be starting to experience the same symptoms as the one at school. I've heard that other smiths who have these newer models have also experienced similar problems. Check it out ASAP before any major damager gets done!

[Kallsme´n]

I have not work with Kuhn hammer but I hawe a lot of experience of Beche´hammers.

I think you should look att the rubberseal round the bar.
If there is blowing air around the bar when its running,
i would say thats the problem, change the seal around the bar and
i think your problem will be solved.

If the hammer goes without oil in the two cylinder, the seal will be damage wery quickly.and there will bee a leak of air.
Oil line must goes in to the compressorcylinder to grease ewen the barcylinder.


I don think its the piston or the bar rings that failure.

Hope you anderstand my bad english

Kallsme´n