Besides, centering and tack welding by laser beam should be avoided as centering point and tack-welding point can influence weld quality largely.
但焊缝质量受激光对中点和点焊点的影响很大，应尽量避免采用激光对中及点焊。
Tack weld shall be the same with welding process of formal welding.
定位焊应与正式焊接的焊接工艺相同。
Assemble and fit metal sections and plates to form complete units or subunits using tack welding, bolting, riveting or other methods.
采用点焊，螺栓，铆接或其他方法，组装金属型材和板，以形成完整的单元组或亚单元组。
Internal bolts subject to vibration, fluctuating load, impact load or dynamic load shall be protected against loosening. Double nuts, unti-loose washers, tack welding, etc. shall be used.
可能受到振动、波动载荷、冲击载荷或动力载荷的内部螺栓应加以保护防止松动。可采用双螺母、防松动垫圈、点焊等。
During welding operations, except for tack or spot welding, insulation material to be removed in way of the welding.
焊接操作期间，除非间断焊和点焊，绝缘材料应从焊接处移开。
It is recommended that when welding around a perimeter, a series of tack welds should be used.
建议在焊接时焊缝周围的边界，大头钉的一系列应使用。
It is recommended that when welding around a perimeter, a series of tack welds should be used.
建议在焊接时焊缝周围的边界，大头钉的一系列应使用。
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