A Little Something Different In Machine Work

[jackieschmidt]

A while back, one of our shipyard customers got the contract to completely rebuild a 24” suction Dredge Boat.

One of the items that had to be rebuilt was the Hinged Spud Housing, which pivots on a 10 inch pin.

All of the bushing fits were in terrible shape and needed to be align bored. So they had us come out and Aline bore the Spud Mount and the Hinge Abutments, then machine new bushings and install them with liquid nitrogen.

It was a pretty good job. I used our 4”x 14’ bar one the Spud Mount, and and our 3 1/2 inch 7 ft bar on the Hinge Abutments. The last pictures are one of the new bushings after installation and being shrunk in the liquid nitrogen.

I don’t get to do out of the ordinary jobs like this very often, so I look upon these as a challenge,

 

[Shooter13]

Nice! So you're sayin' that a lil' ol' barrel ain't nothing? ;-) That truly is amazing stuff you do!

 

[Bill Norris]

Nice work Jackie.

 

[Dusty Stevens]

Great job jackie. I was always amazed at guy’s creativity when dealing with machining on site like that. Ive had guys bore turbine bearings and bearing housings that would take days to set up and run.

 

[Jtate]

I love to read about and see photos of the work you do.

 

[6milphil]

You ever do Ajax crosshead guides?

 

[jackieschmidt]

You ever do Ajax crosshead guides?

I assume you are talking about large gas compressors. The answer is no.

We are dedicated to the Marine Industry, and do very little work that is not directly related To the Marine Industry.

That being said, we will tackle anything that comes out of a Shipyard.

 

[Daddymac]

Really interesting stuff, looks like you have built some mounting frame work for the boring rig but how do you center it, what does the cutting tool look like, what kind if tolerance will it hold end to end, do I sound like a four year old?

 

[Daddymac]

And another question, did you have to bore the bushings after installation? In my simple mind if you if you built the bushing with the correct OD and ID, shrunk it for installation, and it expanded back to some level of interference fit, wouldn't the bore be under sized?

 

[akajun]

There’s a guy on YouTube Curtis from cutting edge engineering that has a lot of line boring videos. He shows the setups, boring, cutting, etc pretty much what you just showed if anyone doesn’t understand what Jackie has done
Nice work

 

[jackieschmidt]

And another question, did you have to bore the bushings after installation? In my simple mind if you if you built the bushing with the correct OD and ID, shrunk it for installation, and it expanded back to some level of interference fit, wouldn't the bore be under sized?

The bushings are machined for the required shrink fit on the OD and the ID is bored to the correct clearance plus the amount of closure Induced by the shrink fit.

So the answer is no. The bushings are not bored after installation.

As a note, we install the bushings by shrinking them in liquid nitrogen rather than pressing them in to avoid any galling.

 

[ragsflh]

great work

 

[jackieschmidt]

Really interesting stuff, looks like you have built some mounting frame work for the boring rig but how do you center it, what does the cutting tool look like, what kind if tolerance will it hold end to end, do I sound like a four year old?

For this job, we used .031 music wire with a 100 pound weight Broke over a 4 inch radius. You lay your alignment marks off of the wire on each side of the hole to be bored.

you then mount the bar by securing it in the adjustable strong backs. You can then align the bar to the reference points that you established off of the wire. You can see the small center punch marks in the white circles on the face of each abutment.

basically, I am placing the wire in the exact location required, then mounting the boring bar exactly where the wire was.

If you look at the 4th picture down in my original post, you can see the cutter head and the rough cut.

these bars bore round and straight, not much different than if we had the piece on our large Lucas Horizontal Boring Mill.

click on the link and it show these bars boring the Struts and Stern Tubes on a new Pushboat

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjKmJ2poqX3AhUjg2oFHVuOBasQuAJ6BAgHEAc&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DNgFpC6jBdJU&usg=AOvVaw0h1tCBzsbQAi9-pymyfH-U

 

[okie]

This is what makes America GREAT!!!
I hope someone is paying attention and learning from you Mr. Schmidt---not many people with skills like you posess these days. thanks for posting!

 

[Will Henry]

I used to work in a shop (over twenty years ago) where most of our work was for the mining and sawmilling industries and a lot was similar to what you are doing but usually not as large. The owner of the shop was absolutely unable to refuse a job so it was always interesting and challenging. I like your pictures. You need a YouTube channel. WH

 

[jackieschmidt]

I used to work in a shop (over twenty years ago) where most of our work was for the mining and sawmilling industries and a lot was similar to what you are doing but usually not as large. The owner of the shop was absolutely unable to refuse a job so it was always interesting and challenging. I like your pictures. You need a YouTube channel. WH

Will, years ago we did work for a big Smelting Plant in East Houston called Tenn-Tex Alloy and Chemical.

They had three huge electric furnaces that were used in making Ferous/Manganese and Silico/Manganese for the steel industry. They sold 90 percent of their product across the street to Armco Steel.

When Armco shut down in the late ‘70’s, they went bankrupt.

I used to marvel at the huge train loads of ore coming in from various mines. Much of their equipment came from mines, mainly two huge rock crushers and six huge Roots/Connervill Blowers that were used on the fume system. Those Rock Crushers each had 1000 HP electric Motors, and Those huge positive displacement blowers 1500 HP through a reduction gear. They we’re about this size.
They had purchased them from a mining company where they had been used to scavenge and pull fresh air into deep shafts. We rebuilt all six.
those machines are where I learned to pour, machine, and scrape in Babbit Bearings.

A story you might enjoy. They had an old fellow that went around every morning and checked the oil levels in all of their machinery. He had taken the big 2” pipe plug from top of the timing gear case on one of the blowers and dropped it on the ground.He went to the warehouse to retrieve a replacement but picke up a 1 3/4 pipe plug by mistake. When he went to screw it in, it just fell right trough the hole, right smack in the middle of the timing gears. The inertia from the violent stoppage literally split the outer housings as the lobe shafts were pushed apart.

It made a mess.

 

[Bill Norris]

When handling these huge pcs. of equipment do they ever try to get away from you like falling or turning over ?

 

[55fairlane]

I have never done any "on site machining " but I did use a similar set a couple times to fix equipment in the shop....more power to you guys! I will stay in the tool room!

 

[6milphil]

I assume you are talking about large gas compressors. The answer is no.

We are dedicated to the Marine Industry, and do very little work that is not directly related To the Marine Industry.

That being said, we will tackle anything that comes out of a Shipyard.

Yes sir.
Very similar tooling. Thought we may have met a time or two.

 

[JoeMcNeill]

Jackie,
Any truth to the rumor that they are bringing the USS Texas to your shop for shaft/propeller replacement?
Might be an interesting job.

JDM