Custom Made Spanner/Wrench Heat Treatment
Custom Made Spanner/Wrench Heat Treatment
(OP)
Hello all,
I am tasked with creating the drawings for a set of special spanners, not something we can buy. We made one set before out of 304 stainless but after some use they started to deform. So I need to get more made and want to specify some more durable material probably with necessary heat treatment so the tools last. Also don't want any corrosion problems, hence why it was stainless before.
Could someone suggest any materials/treatments please as I am not very familiar in this area. I have been reading a bit and maybe it could be a medium carbon steel that is hardened and tempered, but I do not know how I would quantify that on the drawing. I do not know what hardness values would be acceptable, how to specify tempering. Maybe there are different treatments for stainless?
Hope someone can help
Thanks.
I am tasked with creating the drawings for a set of special spanners, not something we can buy. We made one set before out of 304 stainless but after some use they started to deform. So I need to get more made and want to specify some more durable material probably with necessary heat treatment so the tools last. Also don't want any corrosion problems, hence why it was stainless before.
Could someone suggest any materials/treatments please as I am not very familiar in this area. I have been reading a bit and maybe it could be a medium carbon steel that is hardened and tempered, but I do not know how I would quantify that on the drawing. I do not know what hardness values would be acceptable, how to specify tempering. Maybe there are different treatments for stainless?
Hope someone can help
Thanks.
Regards,
Jon Reynolds





RE: Custom Made Spanner/Wrench Heat Treatment
Next, consider environmental exposure (corrosion, H2S, Chlorides, etc...)
From these, you can see which materials are available in the product form you need to satisfy cost/delivery requirements.
rp
RE: Custom Made Spanner/Wrench Heat Treatment
Most spanners are alloy steel that is quench hardened and tempered or austempered. These would have low corrosion resistance without a surface treatment. A variety of surface treatment options are available, including zinc-rich coatings, zinc or zinc alloy electroplating, even physical vapor deposition (PVD) coatings.
RE: Custom Made Spanner/Wrench Heat Treatment
These will age harden to fairly high strength with a simple 1000F treatment after rough machining.
You would then want to finish grind the precision dimensions.
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Plymouth Tube
RE: Custom Made Spanner/Wrench Heat Treatment
I have not seen tools like a spanner made from 304 cres. In fact, I have not seen many wrench tools made from stainless steel at all. Wrench tools are usually made from alloy steels, and if they require corrosion protection they are plated with chrome or nickel. There are some wrenching tools that are made from high strength bronze alloys intended for applications where they must not produce sparks. And there even some wrenching tools made from titanium that are designed for use with titanium fittings, in order to prevent surface contamination of the titanium fittings from contact with the wrench tool.
RE: Custom Made Spanner/Wrench Heat Treatment
What "clearance" or size limits do you have?
What tolerances can you live with to make them work? (Too tight, and the workers can't slide them on the nuts and bolts.) Too loose, and the wedging action of each nut will bend the wrench opening too wide.
Now, why can yo not make the head larger (thicker, wider, taller) so there is more meat in the head to resist failure with a slightly lower strength material or the same strength with more material at the corners or depth?
RE: Custom Made Spanner/Wrench Heat Treatment
RE: Custom Made Spanner/Wrench Heat Treatment
Thanks for the useful replies. I am uploading a photo (as photos are always nice) which shows the wear on the spanner.
Basically, it looks too soft as there are indentations on the working surfaces and also the C is starting to taper, as it must be getting splayed open.
Not sure if I need to re-design or can just remake in a stronger material/heat treatment. Its not used very often, but obviously often enough that it is not surviving in 304.
Thanks again.
Regards,
Jon Reynolds
RE: Custom Made Spanner/Wrench Heat Treatment
Regards,
Jon Reynolds
RE: Custom Made Spanner/Wrench Heat Treatment
Is chrome-plating more expensive? It might be deemed overkill if it costs too much. This tool is not used that often.
Regards,
Jon Reynolds
RE: Custom Made Spanner/Wrench Heat Treatment
RE: Custom Made Spanner/Wrench Heat Treatment
If you have the ability to machine the wrench flanks with a complex profile, you can machine them with a slight crown so that they contact the bolt/nut flats away from the corners.
RE: Custom Made Spanner/Wrench Heat Treatment
RE: Custom Made Spanner/Wrench Heat Treatment
Thanks for the answers. Tbuelna that's a great idea. I might be able to incorporate that crown.
racookpe1978, yes unfortunately it does need to be that thin. Working in a small place necessitating the thin tool.
Cheers all.
Regards,
Jon Reynolds
RE: Custom Made Spanner/Wrench Heat Treatment
They make a lot of custom spanners in 17-4PH, Custom 465 or 420