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Seeking a cast iron reparation method without welding

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zen2000

Mechanical
Aug 2, 2001
6
US
I have faced the casing of gear box was cracked. Do you can suggest me how to repair it without welding method or suggest the expert company?
 
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There are some glues that are made for cast iron. I don't remember any brand names. The ones I have used in the past did a good job.
Hope this helps
Francois
 
The crack point is the seat that bearing sit on it . Mr.fjbalux, you think that the glue you suggested is conform? If yes please let me know the name or way to contact vendor.
Thank you in advance
 
I don't remember the name of the glue I used but you can test some types on broken cast metal parts. I think it should do the job on a bearing seat but it's hard to tell because I can't see the part.
Francois
 
please provide info on stresses this casing must resist. if sresses are involved then metal stitching would be a viable option. glues, no matter how good, will only handle limited stresses. if only used in a filler capacity i see no problem with a glue or epoxy filler. what is the consequence at a failure? all this must be considered.
 
I believe the product you are looking for is called "quick metal". It is used for a variety of applications and appears to be what you need.

Good Luck,
John Schrock
 
Try, I've had some good results with Devcon products in the past. But depending on the loading of your part you may just have to bite the bullet and weld. If you're lucky you may be able to build up the area, with one of the "liquid metals", and then machine to tolerances.
 
My experience has been with both welding and pieces similar to the one described below. Welding is sometimes difficult, even following the procedures.
But if for some reason you cannot weld, sometimes you can bolt something. I dont know your geometry or loads, but using a milling machine you could machine a centered hole, and a face on the gearbox case. Then on a lathe, you could manufacture a flange that will be fixed to the machined face with bolts; this flange can be easily machine to receive your bearing. The flange will center with a lip on the hole. To apply the bolts you can thread the case itself, or use some nuts on the interior.
Dissasembly procedure would be slightly modified, since it is possible that you would have to remove the flange to get the bearing or the shaft.
sancat
 
Metal stitchin is prolly what u looking for here, especially if it undergoes cyclic stress.

arnie333
~_~
 
We repair cast frequently by a process called cold stitching. One drills a patern of inter locking holes and then hammers a pre made insert into the hole. Depending on the size of the casting and depth one can place multiple layers. The largest size that I have used is a 5 lobe x 3/8 x 1/4 thick to fill 1 inch deep cavity. The smallest is a 3 lobe 5/32 x 1/16 thick. After placing these accross the crack at fixed intervals (7/8 for a 3/16 lobe)one then fills the rest of the crack with tapered threaded pins. Then peen till your wrist is sore, dress the excess off and you have a relitivly leak proof fix. Stronger than the original so say the manufacturer.
The whole thing, jigs for drilling, tapered taps, pins and the laces all come in a kit...... unfortunately I forget the name and do not have access to that info at the moment.
Works reasonably well though and I have repaired pieces completely broken out that held city water pressure when complete. A frequent repair is the cracks that form on a lobe blower end plates when a rub causes stress cracks. We lace and pin the crack, dress the excess and presumably stop the crack from growing.
Good luck
Ralph
 
That seal-lace mentioned above is from SEAL-LOCK International P.O. Box 308 Glenside, PA 19038 (from an old label)
Hope the have not move....
Ralph
 
What created the crack?. If it was from a hammer blow, then structural damage may not have occured and a glue may work. If it was from overloading then you have structural problems which glues/fillers are useless. If the crack began from a bearing seat/bore you may not want to waste your time. If the value of the box justifies repair, then weld it. But you'll want to prepare a plan to deal with the bearing seat/bore after repair to return it to tolerance. You may be into boring, sleeving, filling, dimpling or a host of other options.
 
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