Commercial chiller help and advice

This story would be funny if it happened to anyone else. Enjoy if you must, help if you can.

We are proud owners of a 40 year old York chiller. It is unique in the industry for having an electric block heater that resides in a well in the cast iron block of the compressor. The compressor will not start unless the oil temperature is high enough (the cast iron gets hot to the touch, probably ±140°) to prevent pumping Freon 11, a notorious solvent, through the bearings. The heater is about 8" long and 5/8"? made of stainless (no I don't know what grade) with ceramic and a heater coil sealed inside. You would also need to know that due to controls, framing, and sensors the path to this well is about 20" away from anywhere you could have a drill motor. The well bore is horizontal. I did not have my bore gauges with me but a 3/4"? drill shank will NOT go in the bore.

The heater shorted and failed and in the process, apparently, welded itself to the bore of the cast iron well. One of our technicians welded a 5/8 reduced shank to a 1/2" rod and launched into the bore. He made some good progress and then snapped the weld, he was able to get the drill back out. No problem, we had made up a 5/8 reamer on a cold rolled shaft for a previous similar problem on a different York. We had used it by turning it with a crescent on some flats. This guy decided that this would be too slow, so he chucked up the shaft in a hand held electric drill. DO I REALLY HAVE TO TELL THE REST OF THIS?

I was invited into this problem late Friday. There is about 1

1/2" chunk of broken off ream in this bore. The end of the piece of ream is 3 1/2" deep in the bore. The ream shattered at an angle. I was able to get a long thin screw driver into one of the flutes, but it is well jammed and I couldn't get anything to wiggle. It was decided not to deal with it until Monday due to Easter and an unusual cold snap.

I drilled a 1/4" hole through a 5/8 bolt to act as a drill guide. I left the head on to keep it at the face of the bore and have a stack of O rings to center it in the bore. I have a new package of taper length 1/4 cobalt bits that can just reach the back of the ream and drill about 3/4". I have a half dozen new 1/4" masonry carbide bits. I can turn the 1/4" bits with 2 Irwin speed bore extensions.

Wish me luck. Say an extra prayer. Hurry up and give me some other advice. Rainy days and Mondays are bad enough on their own, I'm feeling challenged about tomorrow. ______________________________ Keep the whole world singing . . . . DanG (remove the sevens) snipped-for-privacy@7cox.net

Reply to
DanG
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========= There are portable bolt disintegrators or EMD machines. You might call some of the marine repair depots in your area to see who they know, as I understand this is a frequent problem on larger marine engines.

see

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for a one job you might contact these people and see who they sold to in your area.
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Lindsay also has plans to build your own, if you have the time. Looks like a neat project.
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google on for about 21k hits.

Unka' George [George McDuffee]

------------------------------ Watch out w'en you'er gittin all you want. Fattenin' hogs ain't in luck.

Joel Chandler Harris (1848-1908), U.S. journalist. Uncle Remus: His Songs and His Sayings, "Plantation Proverbs" (1880).

Reply to
F. George McDuffee

Unka George,

I appreciate the information. I had asked at the only industrial supply we still have if there was such a thing as a portable EDM and was told no with quite a smile, as in - are you nuts?.

I will certainly call Camman early to see if anyone has the machine locally. I have my doubts and need to be prepared to attempt my other ideas.

Reply to
DanG

Stick a piece of 1/4" pipe centered over the reamer and sticking up some

4 inches..and run a 6011 welding rod down the center of the pipe and hit it with the juice. Burn it in for a second or two.

It may..may(usually) weld the pipe to the busted stub and you can twist and yank the stub out.

Btw..Ive got a couple bushell baskets full of similar heaters. Mostly Big Chief brand, used for heating injection moulds.

If dat don work..ya be well and truely f***ed.

Haste..makes waste.

Gunner

A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects. Lazarus Long

Reply to
Gunner

We talked to our welder Friday. I hadn't thought of isolating away from the cast iron and creating a handle with the gas pipe. We had talked about using some stainless rod for the strength, but the concern was that the SS rod would bond to the cast. I will certainly bring this up in the AM.

Huge, high amps? or make an honest attempt at striking and maintaining an arc down in a blind hole? I assume you are talking about starting the welder after the rod is down in the shaft touching or almost touching the reamer.

Reply to
DanG

========== In ideal world there would be a law requiring all mill supplies to have the RCM and AMC addresses and directions on how to subscribe and post prominently displayed at their counter or on their website.

Both of these are fantastic groups and it is a rare day when I don't learn something interesting and/or useful, even if it is sometimes off topic.

Good luck to fixing the fix that fixed the problem....

Unka' George [George McDuffee]

------------------------------ Watch out w'en you'er gittin all you want. Fattenin' hogs ain't in luck.

Joel Chandler Harris (1848-1908), U.S. journalist. Uncle Remus: His Songs and His Sayings, "Plantation Proverbs" (1880).

Reply to
F. George McDuffee

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There is and I have one in the shop. Eliox tap burner. We have it mounted on a rolling table but it has a electromagnetic base that can be used anywhere. it sure saves our butt when we are tapping hard castings. It will remove a 5/8 11 tap in about a minute.

John

Reply to
John

On purely metalworking terms, this makes sense. Somehow I'm getting the idea you don't want to dismantle this machine. The idea of the disintegrator burning through the crankcase and manufacturing a sizable blast of phosgene gas before somebody realizes a catastrophe has begun runs through my mind.

I would first look at the possibility of simply abandoning this heater, and attaching some kind of external heaters to the crankcase. It probably would take several smaller heaters attached to the block to achieve the same internal oil temperature.

If you have to get the bore cleaned up, and these simple procedures have made things worse, I would certainly evacuate the R11 from the unit, and probably open up the compressor, at this point. Then you won't have a major mess if you end up breaking through the side or bottom of the hole.

Jon

Reply to
Jon Elson

\ Correct..whatever your welder thinks will work in bonding the reamer stub to the pipe. Id hit it hot and hard..shrug..but its not my chiller either.

Gunner

A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects. Lazarus Long

Reply to
Gunner

Excellent suggestion!

A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects. Lazarus Long

Reply to
Gunner

We have already discussed an alternate heater. Fast, quick, easy, uncontrolled--wire some quartz lights to the volute. We discussed one or several heat guns, but I don't think they would do well as continuous run, and, again, there would be no control. Here again, any advice or suggestions are welcome.

When the heater is working, it takes it about 12 hours to bring the block up to temperature depending on the ambient temperature.

Reply to
DanG
40 Year old York chiller with R-11, how much $ do you want to invest in this? I'd get a CFC EPA certified tech to recover the system before you cause a major leak.. Then make an attempt to remove the bad heater. Adding a external heater is an option, but you need to make sure you know how to control the oil temperature, most chillers will need 130 -140 Deg F oil. Oh, it will start without it being up to correct oil temperature, its called a jumper wire across the relay contacts.... but then its new chiller motor time when the bearings go out. BG

Reply to
MachineShop

You already know it is past time to replace the chiller, that handwriting has been on the wall for several years. We have been converting sites to geothermal heat pumps as dollars permit, but this old beast has been rebuilt and has been rock solid other than this heater problem.

No, we don't want to spend huge money on this old chiller; but a new one is $50 - 100,000 with some pretty substantial lead time.

Reply to
DanG

Lots of good advice but I wonder if an acid soaking might erode it enough to loosen it with little risk of significant damage? I know that nitric acid will dissolve steel and has been used to etch and sharpen dull files.

Don Young

Reply to
Don Young

Good stuff..lots of varieties...

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Gunner

A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects. Lazarus Long

Reply to
Gunner

When you get the remains of the old heater out, you *are* going to stuff the annular space of the heater bore with silicone heat-sink grease to lower the odds of this happening again, right? ;-)

And another thought is an equipment (30ma trip) GFCI Breaker on the heater line to trip out if it grounds again, /before/ it welds...

(Fool me once, shame on you Fool me twice, shame on me.)

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Reply to
Bruce L. Bergman

Yes, Bruce, it is normal procedure to fill the annular space for heat transfer. Apparently this is the original heater, or at least, not changed in anyone's recollection.

Reply to
DanG

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