“预拉”用英语怎么说

预先装配的平行钢丝索与结构钢缆相比, 不需要预拉.Preassembled parallel wire strands, in contrast to structural strands, do not require prestretching.分析了7075-T651合金厚板预拉伸断裂的原因.The crack causes for pre - stretching plates of 7075 T 651 alloy are a...