Talk:Semi-finished casting products

2008-03-13 Automated pywikipediabot message

--CopyToWiktionaryBot (talk) 21:49, 13 March 2008 (UTC)

Centrifugal casting billets

I don't think this should be included because the paragraph says that its not a semi-finished product, which defies the title. Seeing how bar stock is sometimes incorrectly called billet, I included a dab temp at the top of the section. I think the same should be done in this instance that points to centrifugal casting. Wizard191 (talk) 20:59, 24 March 2010 (UTC)

The paragraph doesn't say that - it says that they're arguably both included and excluded from this group. Centrifugal casters tend to include them, makers of billets for re-rolling tend to exclude them. In the absence of any clear position one way or the other, I'd suggest that the best position for an encyclopedia is to be inclusionist. Andy Dingley (talk) 21:53, 24 March 2010 (UTC)

Oh, I read it a little closer and see that it says they are "unfinished but will not be processed further sufficiently to significantly change their dimensions". How then are they processed if it doesn't change their dimensions? Because if they are processed later, dimensionally or not, I would agree that they are semi-finished products, and then drop this issue all together. Wizard191 (talk) 22:08, 24 March 2010 (UTC)

If you can think of better wording, go for it - I can't. Billets for rolling are cast to be just small enough to still fit on a truck, then rolled until they're the size of toothpaste tubes. Centrifugal cast cylinders just get the outside crud skimmed off and ground to an exact size (if you aren't bothered about surface finish, you weren't buying this stuff). One ends up a lot smaller, one doesn't. Andy Dingley (talk) 22:35, 24 March 2010 (UTC)

Well it sounds like you are saying that billets are cast using the c.c. process but then are further processed (maybe cutting to length or changing the ID?), so this this does sounds like a semi-finished product. It just doesn't go through the typical primary rolling process that continuously cast billets do. I'll see if I can reword it to clarify. If I change the meaning too much, please correct me. Nevermind, I finally understand what "As these are unfinished (they will usually be ground to size)" means. You are saying that after casting it will be processed via grinding and then directly used (in what application?), correct? Wizard191 (talk) 23:51, 24 March 2010 (UTC)

They're ground for several reasons: sizing, removal of crud layers (columnar metallurgy is an important part of their virtues - top and bottom are waste, for not having the best crystal sturcture) and particularly for achievement of a surface finish. The biggest single market for these is cylinder liners, where that's important. Andy Dingley (talk) 00:02, 25 March 2010 (UTC)

Fascinating; I see how it's tough to classify the product. I think I'll try and reword it to make it clear that the grinding is done outside the foundry and let it be otherwise. Wizard191 (talk) 00:26, 25 March 2010 (UTC)

Billet Casting

Wizard191 (talk | contribs) (Reverted good faith edits by MarkBolton; It's "direct chill casting" not "drop casting"; and it's ingots that are cast, not slabs or billets. using TW)

I believe that you are incorrect, I work on a day to day basis installing equipment in Aluminium Cast houses where Billet are cast By Direct Chill Drop Casting, as opposes Direct Chill Horizontal casting (which is effectively a continuous casting machine), I refer you to the world leading suppliers website [1].

MarkBolton (talk) 04:26, 26 March 2010 (UTC)

Hrm, there's nothing on your link that states it's a "drop casting" system. Please provide a reliable source that explains the system and then add it to the article. Wizard191 (talk) 12:42, 26 March 2010 (UTC)

The distinguishment should be made however between Direct Chill Vertical casting(Refered to in the industry as Direct Chill Drop Casting due to the start of a "drop" being the start of a batch) and Direct Chill Horizontal casting, in both the Billet and Slab as one is a batch process whereas the second can either be batch or continuous.

Currently in Billet casting it states Billets are created directly via continuous casting or extrusion or indirectly via rolling an ingot and in Slab "It is created directly from continuous casting or indirectly by rolling an ingot." so there is a complete process missing in the fact that there is no mention of Batch production

The article should be expanded as differing processes are used for different metaullurgy, currently the article is biased towards Steel production only. MarkBolton (talk) 07:03, 12 April 2010 (UTC)

You are right that it is mostly based on steel production, because that's what the sources I have are about (although Andy did add something about centrifugal casting). Feel free to add the above as long as you have a reliable source to cite. Wizard191 (talk) 18:09, 12 April 2010 (UTC)