By the analysis and comparison of upsetting extrusion and cold forging technology,the upsetting extrusion technology on the countersunk square neck bolt is introduced in the paper.

• 通过两种工艺方案中成型凹模受力情况的分析比较,说明用镦挤工艺生产沉头方颈螺栓,可降低镦锻力,提高模具寿命,保证零件质