标准件紧固件知识讲座.ppt

《标准件紧固件知识讲座.ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、标准件/紧固件知识讲座螺纹的主要几何参数圆柱螺纹的主要几何参数螺纹的测量螺纹中径可以用三针螺纹千分尺、万能工具显微镜测量螺距测量：万能工具显微镜测量螺纹牙型角可用万能工具显微镜测量对大批量生产的螺栓、螺钉、螺母均采用综合测量法即用螺纹环规、螺纹塞规的通规进行测量螺纹的加工1、车削切削加工单件生产2、搓丝挤压加工大批量中低精度3、滚丝挤压加工大批量高精度普通螺纹的公差与配合1、普通螺纹直径公差带2、螺纹的旋合长度3、螺纹公差与配合的选用普通螺纹直径公差带螺纹的旋合长度GB/T197-1981规定了三组螺纹旋合长度：S代表短旋合长度；N代表中等旋合长度；L代表长旋合长度。各种旋合

2、长度螺纹副的特点是：短旋合长度螺纹副旋合稳定性较差，但加工精度易于保证；长旋合螺纹副旋合稳定性较好，且联较强度高，但加工精度难以保证，甚至出现螺纹副不能旋合的情况。而中等旋合长度螺纹副的特性则介于S组和L组螺纹副之间。一般情况下应采用中等旋合长度。旋合长度的数值规定见表：螺纹旋合长度公称直径D、d螺距P旋合长度公称直径D、d螺距P旋合长度SNLSNL>≤≤>≤>>≤≤>≤>0.991.40.20.50.51.41.42.85.60.3511330.250.60.61.71.70.51.51.54.54.50.30.70.7220.61.71.7551.42.80.20

3、.50.51.51.50.722660.250.60.61.91.90.752.22.26.76.70.350.80.82.62.60.82.52.57.57.50.41133111.20.51.61.64.74.70.451.31.33.83.80.752.42.47.17.133991.2544121211.222.40.51.81.85.45.41.5551515459014.84.814140.752.72.78.18.11.57.57.5222213.83.8111129.59.528281.254.54.513133151545451.55.65.61616419

4、1956561.7566181852424717128824345.5282885852.51010303063232959522.4450.753.13.19.49.4901801.58.38.3252514412122121236361.56.36.3191931818535328.58.52525424247171312123636636361061063.51515454563552131338384181853533202060604.5212163634262680804040118118螺纹旋合长度公称直径D、d螺距P旋合长度公称直径D、d螺距P旋合长度

5、SNLSNL>≤≤>≤>>≤≤>≤>0.991.40.20.50.51.41.42.85.60.3511330.250.60.61.71.70.51.51.54.54.50.30.70.7220.61.71.7551.42.80.20.50.51.51.50.722660.250.60.61.91.90.752.22.26.76.70.350.80.82.62.60.82.52.57.57.50.41133111.20.51.61.64.74.70.451.31.33.83.80.752.42.47.17.133991.2544121211.222.40.51.81.85.4

6、5.41.5551515459014.84.814140.752.72.78.18.11.57.57.5222213.83.8111129.59.528281.254.54.513133151545451.55.65.616164191956561.7566181852424717128824345.5282885852.51010303063232959522.4450.753.13.19.49.4901801.58.38.3252514412122121236361.56.36.3191931818535328.58.525254242471713121236366363

7、61061063.51515454563552131338384181853533202060604.521216363426268080640118118118螺纹公差与配合的选用普通螺纹公差带一般按表6-6选用。对于不同旋合长度组的螺纹，应采用不同的公差等级，以保证同以精度下的螺纹配合精度和加工难易程度相当，并减少量刃具的规格。内外螺纹的极限偏差值见表6-7普通螺纹选用公差带螺纹精度内螺纹外螺纹选用原则SNLSNL精密4H4H,5H5H,6H(3h,4h)*4h(5h,4h)用于精密螺纹，当要求配合