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Rarely gets below 10 degrees Celsius where it works. It was a hot day, above 20 degrees C when it failed.

It was supposed to be quenched & tempered, the foundry is being very sketchy with what they did. We are not going to use them anymore.

An update, just got hands on some preliminary mechanical tests results: Material is too brittle, for Charpy our specs ask for 40J at -40 degrees C. Also Tensile strength is some 200 MPa below our minimum requirements. Chemical analysis meets specs, so may be they didn't tamper it to high...

"gtaw (Structural) 8 Jan 17 16:26 Was the pin that passed through the two aligned holes bent after the failure? ................. Small repairs, without the benefit of preheat on a thick casting, could still experience high hardness if the weld cooled quickly. Did they repair the casting using...

"MJCronin (Mechanical) 8 Jan 17 14:29 Where was the casting made ??? Which foundry is responsible" This is the first time we got castings made by this foundry. We never had any such issues in castings from our regular foundry. They were bit too busy so we decided to try this new one. On paper...

WKTaylor (Aeronautics) 6 Jan 17 17:51 "... Any idea RE lowest temperature that the failed casting reached 'during the holidays'?? Carbon steel fracture/impact toughness typically decreases rapidly with decreasing temperatures... especially with certain impurities and/or miss-processing and/or...

"Based on the tool-bag in the background, this looks like a very large casting [several hundred #s], with very deep/thick sections. " Yes it's a quite thick casting. I should have included some dimensions, my apologies. The section that broke is 100 mm thick.

"Sounds like these are being made just for you. Are you requesting/requiring test coupons for each pour that will be subjected to mechanical testing? Regardless, maybe cutting some test coupons from the failed ( and a few un-failed) pieces and testing them is in order." These castings are our...

Material is cast steel (Avg 0.2% C, 1% Mn, 1.8% Ni, 1% Cr, 0.4% Mo) with yield strength of minimum 700 MPa. Repair weld was done by the foundry without our knowledge, we found out only after it failed. Foundry is supposed to tell us before doing any kind of repair. We are using this foundry for...

Definitely I will. BTW, I have opened another thread for this new failure here: http://www.eng-tips.com/viewthread.cfm?qid=419104

Continuing from this thread: http://www.eng-tips.com/viewthread.cfm?qid=418786 Taking the sound advice & opening a new thread as it's a different part. This casting failed over the holiday break. Here are the shots of fracture surface: All these ridges and facets, does this look like...

This later casting is from a different foundry, we are using them for the first time. Similar designs have been working in other sites for years with failures occurring very very rarely. First casting is from a foundry that we've been using for quite some time & hasn't seen problems like this...

Thank you very much for the valuable comments, much appreciated. Testing services are just starting to open their doors after holidays, I'll be visiting them soon with this. Meanwhile, as a part of universal conspiracy to ruin my vacation another casting failed over the holiday break. This...

Thanks. Steel is 0.2%C, 1%Mn, 2%Ni, 1%Cr. Quenched & tempered to 650 MPa yield strength & 25 HRC. Mag particle & RT was done by the foundry. I am yet to get the radiographs but they say they had category II gas porosities (ASTM E186 & E280) in region where it failed. There are two of these...

This is a cast steel spelter socket. Failed after 24 hours of service. Trying to guess what might have been the issue before sending out for tests. Fracture started here??: Other side of the same leg. Gas porosities??: The legs are bent, yielding after fracture??: Also these opened...

There are four locks that sit inside those four cavities, with studs protruding inwards The protruded part sits inside a groove & keeps the part from dropping. The part sits sloppy, it is not tightened against anything.

The part is designed as a wear protecting shroud so basically not carrying any load. It is expected to get hit by chain links & similar at random interval but we are guessing for a week or so frequency of impact increased by quite a bit. This is a weaker point where you might expect failure...

Several of this part failed recently, all breaking apart at roughly same area. It's made of cast steel (C 0.27%, Mn 0.9%, Si 1.4%, Ni 0.75%, Cr 1.85%, Mo 0.4%; Hardness 43-45 HRC). Just got this one piece here this morning, I'm not sure if I'm reading it right trying to guess something from the...

Thanks for the input, highly appreciated.

Hello, We make these cast steel tips for dragline buckets. Several failed recently, failure rate much higher than usual. We had a batch of these tips hardfaced on top, front, side and bottom faces. Hardfacing didn't cover full face, just few ~20 mm wide weld lays of hardfacing metal. All the...