Shop related threads

[Dr Stan]

(12-01-2016, 03:01 AM)awemawson Wrote: Do you chaps REALLY mean cast iron for your pipe. Surely not, it's far too brittle. Black iron fittings are usually malleable iron, and the pipe is mild steel

It still tends to be called cast iron on this side of the pond, although the term black iron is also used.

[TomG]

Andrew,

Malleable iron is simply white iron, which is brittle, that has been annealed to make it malleable. "Cast" is a process term, not a type of iron.

Tom

[awemawson]

And the pipe, Tom - not cast surely ?

[Dr Stan]

(12-01-2016, 11:58 AM)awemawson Wrote: And the pipe, Tom - not cast surely ?

The larger sizes, I'm guessing 6 or 8 inch & above, are centrifugally cast.  I know for certain 1 ft & above are made this way and were used for water mains for a long long time, but have been replaced for the most part with plastic.

If one looks at the black iron pipe you'll see where it has been rolled and welded together. Lower pressure fittings have parting lines and a rough surface you can see from the casting process. High pressure fittings (the ones that are used with schedule 80) are forged and have much thicker walls and a smoother finish.

[awemawson]

So in summary, the 'black iron' pipe in sizes you'd use for air distribution in the shop are mild steel not cast iron, which was the point I was making.

[Dr Stan]

(12-02-2016, 02:53 AM)awemawson Wrote: So in summary, the 'black iron' pipe in sizes you'd use for air distribution in the shop are mild steel not cast iron, which was the point I was making.

Yep