Commercial chiller heater - success story

In case anyone was wondering how this project turned out, we did
win.
The broken ream did not respond well to the carbide faced masonry
bit. It did chew chips off the ream when put on light hammer.
Cobalt had no effect and was not worth the purchase. The
chipping away action made the ream fracture at a fairly steep
angle, so I made up a drill guide plug with a steep angle on it to
approach matching the broken ream. Inserted the drill and guide
plug, hammered and turned for a bit. Pulled it out to check
progress and determine if centered. Grabbed custom air tip with
16" tip, stuck it down the bore blowing out chips, dust, coolant,
etc and there was a loud thunk on the concrete floor as the tip of
the ream fell out!!! Only thing I can figure is the angled faced
guide forced the ream to turn and loosen.
Now all we had to do was remove the old heater shell. Sounds
simple. I had two plans, neither of which worked. Plan one -
drill a hole in the bottom end cap of the heater tube to be able
to pump grease and force out the shell. I had even made up a
piston or sorts to maximize a hammer blow on a rod to pressure the
grease (reserved execution for later). Plan 2 - I had
experimented in the shop with another damaged heater and found
that a 5/8-11 tap would start and cut threads in the stainless
shell without just tearing it to bits or swelling it larger than
the bore (prime idea). Tapped about 3/4" of threads in the end of
the shell and was able to remove extension and tap. Screwed in a
3' section of all thread and had rigged a piece of pipe to
function as a slide hammer. We made several attempts at this and
even used an 18" pipe wrench to wind the all- thread into the
shell. We succeeded in stripping the threads off the all thread,
but the stainless shell was still very happy to live in the guts
of the chiller.
Tried the grease idea - boy, was that a mess! But now I figured
maybe it was loosened and it certainly was lubed! Tried the all
thread again, no progress. Getting mad now.....
Went out to the truck rummaging and came up with a 24" long SDS
drive 5/8 masonry bit. It wasn't very fresh or sharp, but what
the hey. Figured if nothing else it would make the shell spin in
the hole. No it wouldn't. But by turning it on hammer and drill
we actually dug into the shell. It did not drill as such, it just
turned to grit. It was the first progress we had made. Drilled a
bit deeper, enough to see another shell from another heater in the
top of the bore. Apparently it had been drilled out before and
they had not gotten all the old one out. Continued on for over an
hour hammering the stainless shell to dust, never did get the
shell to spin or get the old old shell to let go.
Ended up with a clean enough, deep enough bore to allow the new
heater to slide in, wired it up, and walked away. I should be
retired before this heater dies again.
Thanks for all the suggestions and advice. Gunner, my next step
was to try to weld onto that piece of ream; but turned out not
necessary to try.
Reply to
DanG
Loading thread data ...
Thanks for the "rest of the story."
Glad that things turned out OK. Stresses the importance of anti-seize. Were you ever able to determine just what froze the heaters in the hole?
Unka' George ================ When we are planning for posterity, we ought to remember that virtue is not hereditary. Thomas Paine (1737-1809), Anglo-American political theorist, writer. Common Sense, ch. 4 (1776).
Reply to
F. George McDuffee
Great story- thanks for posting the results.
Why does that always work in the shop manual, but never in real life? Every time I tried to pop out a pilot bushing that way, all I ever got was a face full of grease.
-Carl
Reply to
Carl Byrns
No, as all we really brought out was grit. I don't know what of the grit was cast iron, stainless, carbide, or other.
The HVAC technician debated lubing with heat proof grease, but feared the long term heat (600 watt to maintain 140) might cook the grease??? He ended up installing it bare back. I would appreciate additional input about this decision. Is this a question to the grease manuf, the heater manuf, or the chiller manuf?
Reply to
DanG
=============== I don't know about heat resistant grease, but high temp antisieze might have helped. see
formatting link
?PMAKA=307-3456&PMPXNO=8204937&PARTPG=INLMK3
formatting link
always used Permatex
formatting link

Unka' George ================ When we are planning for posterity, we ought to remember that virtue is not hereditary. Thomas Paine (1737-1809), Anglo-American political theorist, writer. Common Sense, ch. 4 (1776).
Reply to
F. George McDuffee
Usually the reason you want the bearing out is because it is worn so the plug you put in is the wrong size. Shrug.
Carl Byrns wrote:
Reply to
RoyJ
Good GAWWWD! I'm sure glad I don't run into stuff like this in my line of work! What a horror story. Glad you finally got it bored out.
Jon
Reply to
Jon Elson
Good stuff. I usually use the copper antisieze except on aluminum
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

Site Timeline

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.