The workers carefully uncrated the newly arrived machine from the wooden box.

uncrated 是动词 uncrate 的过去式，uncrate 由前缀 un-（表示"去除、解开"）和名词 crate（"板条箱、木箱"）组成，字面意思是"从箱子中取出"，指"拆箱取出物品"的动作。