静态和动态扭矩.doc

Static vs．DynamicTorque
静态和动态扭矩

Dynamic Torque 动态扭矩:

Dynamic torque is the accepted Strategy for fastening in General Motors.This
method is used by the Bosch electric wrehches in Powertrain Assembly
动态扭矩是通用汽车公司认可的拧紧方式。动力总成装配线上的Bosch电动扳手就是使用这个方法.

Static Torque静态扭矩:

Static Torque is the method used when a bolt is rechecked with a manual torque
wrench.Static Torque is not the accepted method for fastening in General Motors．
当用手动扳手重新检测螺栓时，则采用静态扭矩，静态扭矩不是通用汽车公司认可的拧紧方式。

Static vs．DynamicTorque 静态和动态扭矩的比较:

Dynamic torque is much more accurate and repeatable then static torque.There
is normally a difference between dynamic torque readings and static torque
rechecks．The difference depend on the characteristics of each joint and each
bolt．Factors contributing to this difference include：
动态扭矩比静态扭矩更加准确，重复性更强。动态扭矩的读数与重检静态扭矩的读数通常是不相同的．而且不同的粘结点，不同的螺栓，差别程度又有所不同。造成读数差异的主要因素包括：
1．Soft joints(gaskets and sealers)
软性粘结点(衬垫和密封圈)
2．Time after fastening
拧紧的时间
3. Condition of the part(haS ii been run?)
工件的状态(是否已经用过了?)

Do not be alarmed by a difference between the dynamic torque and a statiC
recheck．This is a normal condition．
若发现动态扭矩和静态重检扭矩读数不同，请不要紧张．这是正常现象．

Since a static recheck is less accurate than the original dynamic torque and the
recheck disturbs the good joint，it is not a good practice to recheck good partS．
Static rechecks should only be used during repairs，rejected parts analysis or as
part of a teardown audit．DO not statically recheck good engines or transmissions.
由于静态重检不如原先的动态扭矩准确，而且还会损坏好的粘结点，所以对合格工件进行重新检测不是一个好方法．静态重检应只限于工件返修，工件故障分析或工件拆卸检查．不要对好的发动机或变速箱进行静态检查．

A database of static vs．dynamic values will be developed as part of the
teardown audits by the quality department.This is the only reliable way to gather
sufficient data to understand this problem．
通过工件拆卸检查，质量部将制定一张静态和动态数值对比表．这是唯一一个较为可靠的数据收集方法，能帮助我们更好地理解问题．

扭矩枪紧固螺钉通过传感器显示的动态扭矩，而你用扭力板手检测其松动扭矩，这个时候你是检测其静态扭矩，这个扭矩比上面一个扭矩低很多。规范要求的一般为动态扭力。所以不能说明你这个扭矩不符合规范。建议你同时用扭力板手检查螺栓滑牙时候的扭矩，如果这个扭矩小于规范，说明扭矩不在范围之内；