Peb cov khoom tseem ceeb yog high-frequency ncaj seam welded steel kav thiab ob-sided submerged arc welded steel kav, thiab lwm yam., uas yog dav siv nyob rau hauv nruab nrab thiab tsis tshua muaj siab kua kis pipelines xws li roj, natural gas, dej, chav, roj, thiab lwm yam, nrog rau cov qauv steel kav rau pil ...
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