660 studs, tsis muaj kev sib nqus nyob rau hauv anealed mob, tab sis tej zaum yuav dhau los ua kev sib nqus me ntsis los ntawm vuam. Txawm hais tias nws muaj tib lub zog siab thiab corrosion tsis kam raws li lwm tus hlau, Astm A453 Gr. 660 hex taub hau bolts ua rau muaj zog welds vim lawv cov ntsiab lus muaj roj carbon tsawg. ASTM A453 Qib 660 studs yog qhov haum rau cov ntawv thov kub. Cov qib kawm ntawm cov fasteners tau faib ua A, B, C, D cov qib. Cov ntaub ntawv yog carbon, manghologes, phosphorus, leej faj, silicon, npib tsib, chromenum, titanium, txhuas, vanadium, boron. ASTM A453 Qib 660 bolts tau txais lawv lub zog thiab corrosion tsis kam los ntawm kev sib xyaw ntawm cov ntaub ntawv.