Protect ends with capped self-locking washers incorporating a spring steelinsert to ensure permanent retention of cap in exposed locations.
对外露端部的保护，可采用自锁螺帽加以弹簧垫，以确保螺帽持续牢固的预紧力。
2
Including steel truss, aluminum truss, truss, truss, open booth insert cue rack, tooth column truss.
主要包括钢质桁架、铝质桁架、敞开摊位桁架、插片桁架、球杆网架、齿柱桁架。
3
Later, people tried to lift a building off its foundation, and insert rubber and steel between the building and its foundation to reduce the impact of ground vibrations.