2013-12-20
【網(wǎng)架焊鋼球抗拉極限標(biāo)準(zhǔn)是多少?】網(wǎng)架焊鋼球抗拉極限標(biāo)準(zhǔn)是多少,有誰知道嗎,160x4鋼球,180x5鋼球,200x6鋼球,