My pick would be "一批预制绕线管".

1 lot = a (production) lot
Pipe spool = spool in pipe form


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Note added at 22 mins (2008-02-24 12:57:53 GMT)
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http://www.shinshinpp.com/viewproduct_1_c.html

2. 钢管(carbon steel pipe) 式样
Pipe Spools 制作的光管式样根据定购处所要求的规格单里面明示的 Piping 式样书,一般取如下一种.

These "pipe spools" are called "绕线管" in Chinese, at least in Taiwan. I need confirmation of other Chinese colleagues.


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Note added at 25 mins (2008-02-24 13:00:04 GMT)
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http://www.hcstarck.de/index.php?page_id=731&prod_service_id...

Aha, it is neamed in China "管卷轴".

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Note added at 4 hrs (2008-02-24 16:49:17 GMT)
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I was wrong about 预制 and 绕线管.

One lot of fabricated pipe spools shall be "一批焊接管件" as shown in the following links. Note especially the last one in Chinese.

http://www.appliedcoatings.com/pipe.html

http://www.c-bm.com/tradeinfo/offerdetail/2008/1/9-111-0-501...