Scrap rate in the iron foundry casting industry

[Old Hand - 2009]

Anyone out there associated with the casting industry? If so; what is considered a normal scrap rate for an Iron Foundry using a percentage based on pounds poured vs. pounds scrap?

[Caster]

If you have some money to spend, the American Foundrymans Society has an expensive study that may have the answers.

https://afs.ebiz.uapps.net/SolutionS...ils&args=13198

Based on my unscientific gut feeling experiences in the foundry industry, above 3% scrap seems to be the number where management gets concerned and start improvement projects (or starts heads rolling).

[Stijloor]

In Reply to Parent Post by Old Hand

Anyone out there associated with the casting industry? If so; what is considered a normal scrap rate for an Iron Foundry using a percentage based on pounds poured vs. pounds scrap?

I did an advanced search for you here at The Cove Forums on "Foundry Scrap Rate." Here are the results. Some more exploration through the threads and posts is required.

Stijloor.

[Kevin H]

I spent 3 and half months last year in a green sand foundry casting grey, ductile and compacted graphite cast irons. WRT the scrap rate, a lot depends - how complex are the castings? Well designed and proofed, or start-up of a new part or at a new foundry? We were doing complex castings for the automotive industry - lots of complicated coring. For us the goal was 5% or less, and with some start-up jobs it was a lot higher. For some long term jobs that were pushing the capabilities of green sand casting we were happy with 10%, but that scrap rate had been built-in to the customer cost. We had good capability as far as prototyping and running software to predict solidification in the castings, and still occasionally missed on how the part actually solidified versus how it was predicted to solidify.

We had an in-plant group that regulary looked at scrap rate per part and selected high scrap items to investigate, so we could improve our processes and reduce scrap rates.

We also had customers who wanted and tried to hold us to investment cast tolerances while specifying green sand castings, and only paying for green sand casting.