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液壓伸(shen)縮(suo)式活動(dong)模(mo)(mo)板(ban)(ban)(ban)是(shi)在井筒混合(he)作業(ye)時(shi)(shi)，隨工作面前進(jin)自上(shang)而下現澆(jiao)混凝土(tu)時(shi)(shi)使(shi)用的(de)(de)(de)一(yi)種(zhong)(zhong)(zhong)整體移動(dong)模(mo)(mo)板(ban)(ban)(ban)，它是(shi)我國(guo)各種(zhong)(zhong)(zhong)活動(dong)模(mo)(mo)板(ban)(ban)(ban)中使(shi)用的(de)(de)(de)最(zui)多(duo)的(de)(de)(de)一(yi)種(zhong)(zhong)(zhong)，這種(zhong)(zhong)(zhong)模(mo)(mo)板(ban)(ban)(ban)的(de)(de)(de)基本構造是(shi)：在井筒全部(bu)圓(yuan)周上(shang)，模(mo)(mo)板(ban)(ban)(ban)分為2~3大塊，大塊之間留有伸(shen)縮(suo)縫，依靠某種(zhong)(zhong)(zhong)機(ji)構使(shi)伸(shen)縮(suo)縫伸(shen)縮(suo)以達(da)到模(mo)(mo)板(ban)(ban)(ban)的(de)(de)(de)撐開(kai)和收(shou)攏。