bolt down

基本解释

If find the fire door handle, door locks, bolt (including bolt down), a closed-door, and hinge, the door are in question;
发现防火门拉手、门锁、门栓（包括倒栓）、闭门器、合页、门边有问题；
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When the rubber is injected into the mold, the pressure keeps the bolt down and the rubber molds around the "X" head, completely encapsulating it.
橡胶注塑到模具中时，压力使螺栓下降，橡胶就会完全填满X头。
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You'll suffer from indigestion if you bolt down your food like that.
你那狼吞虎咽地吃东西，会得消化不良症的。

Mr Romney could turn out to be plausible on this criterion: he should tack to the centre in 2012 if he can bolt the nomination down.
ECONOMIST: Christopher Lockwood bemoans reality