| overpass | ทางข้าม, สะพานลอย |
| overturning | การคว่ำ |
| overturning moment | โมเมนต์คว่ำ |
| power shover | เครื่องขุดดิน |
| A Sheet Metal Screw | (english) Sheet metal screws with (a) sharp-pointed ends; and (b) fewer threads per inch than type AB screws; and (c) deeper threads with bettere gripping power than type AB. The industrial Fasteners Institue incorrectly labes type A an “obsolete” thread though it is universally preferred in 18-8 stainless over type AB, especially by the marine industry. |
| Backing Sand | (english) The bulk of the sand in the flask. The sand compacted on top of the facing sand that covers the pattern. |
| Bandsaw | (english) A power saw, the blade of which is a continuous,narrow,steel band having teeth on one edge and passing over two large pulley wheels. |
| Basic Oxygen Furnace (BOF) | (english) "WHAT A pear-shaped furnace, lined with refractory bricks, that refines molten iron from the blast furnace and scrap into steel. Up to 30% of the charge into the BOF can be scrap, with hot metal accounting for the rest. WHY BOFs, which can refine a heat (batch) of steel in less than 45 minutes, replaced open-hearth furnaces in the 1950s; the latter required five to six hours to process the metal. The BOF's rapid operation, lower cost and ease of control give it a distinct advantage over previous methods. HOW Scrap is dumped into the furnace vessel, followed by the hot metal from the blast furnace. A lance is lowered from above, through which blows a high-pressure stream of oxygen to cause chemical reactions that separate impurities as fumes or slag. Once refined, the liquid steel and slag are poured into separate containers. " |
| Beam and Sling | (english) Tackle used in conjunction with a crane for turning over the cope or drag of a mold prior to assembly. |
| Bed-In | (english) Method whereby drag may be rammed in the pit or flask without necessity of rolling over. Process used in production of heavy castings. |