First of all sorry forgot to take a photo to share... so picture this... it’s a 30 tonne drum from a bleach plant at a pulp mill. It’s all stainless except for the shaft to be removed and very expensive to make ($2 million’ish. Drum is probably 14 foot diameter and 40 feet long
Shaft that needs to come out is approx 6 feet long and 10” diameter. Sleeve is approx 5 feet long with a 10” ID and 13” OD. Which makes the sleeve approx 1.5” wall thickness. Shaft is solid and gets a spocket mounted so the drum is chain driven.
Let’s call it a press fit shaft. There’s a lot of weld and gussets supporting the sleeve so removing the sleeve is out of the question.
We think to install the shaft some of the gussets on the sleeve were cut allowing expansion, then the sleeve was heated and the shaft bathed in liquid nitrogen and inserted
Now, inside the drum they have mounted a big brace to support hydraulic rams to push this shaft out. It’s been heated with Oxy/acetalyne rose buds from both the inside and outside trying to expand the sleeve enough to push out... IT WONT BUDGE!
I believed the next step is to add more hydraulics, if that fails then it may have to be repaired in place
I had an idea today but the engineer will think about it... as it’s under immense pressure from the hydraulic rams what about using a demolition jack hammer on the side of the shaft that’s protruding, perhaps clad in a brass pad on the end not to cause any damage to the shaft...
A lot of smart cookies on here, any thoughts on the jack hammer or other ideas? Can take a picture in the next day or 2 if needed
Thanks in advance
It’s something like this. You can see the gussets on the back of the sleeve on the right side of photo
Shaft that needs to come out is approx 6 feet long and 10” diameter. Sleeve is approx 5 feet long with a 10” ID and 13” OD. Which makes the sleeve approx 1.5” wall thickness. Shaft is solid and gets a spocket mounted so the drum is chain driven.
Let’s call it a press fit shaft. There’s a lot of weld and gussets supporting the sleeve so removing the sleeve is out of the question.
We think to install the shaft some of the gussets on the sleeve were cut allowing expansion, then the sleeve was heated and the shaft bathed in liquid nitrogen and inserted
Now, inside the drum they have mounted a big brace to support hydraulic rams to push this shaft out. It’s been heated with Oxy/acetalyne rose buds from both the inside and outside trying to expand the sleeve enough to push out... IT WONT BUDGE!
I believed the next step is to add more hydraulics, if that fails then it may have to be repaired in place
I had an idea today but the engineer will think about it... as it’s under immense pressure from the hydraulic rams what about using a demolition jack hammer on the side of the shaft that’s protruding, perhaps clad in a brass pad on the end not to cause any damage to the shaft...
A lot of smart cookies on here, any thoughts on the jack hammer or other ideas? Can take a picture in the next day or 2 if needed
Thanks in advance
It’s something like this. You can see the gussets on the back of the sleeve on the right side of photo