谁能翻一下，螺栓螺母相关

pengzhh

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) V3 M( ~' ^3 [, V+ O) D& k/ EDoes  it matter whether you tighten the bolt head or the nut?                  

Normally it will not matter whether the bolt head or the nut is torqued. This assumes that the bolt  head and nut face are of the same diameter and the the contact  surfaces are the same (giving the same coefficient of friction).  If they are not then it does matter.

                  

Say the nut was flanged and the bolt head  was not. If the tightening torque was determined assuming  that the nut was to be tightened then if the bolt head was  subsequently tightened instead then the bolt could be overloaded. Typically 50% of the torque is used to overcome friction under the tightening surface. Hence a smaller friction radius will result in more torque going into the thread of the bolt and  hence being over tightened.

                  

If the reverse was true - the torque determined  assuming that the bolt head was to be tightened then if the nut was subsequently tightened - the bolt would be under tightened.                  

pengzhh

不好意思，粘贴上去没看仔细
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乱影lyy

Does it matter whether you tighten the bolt head or the nut?      
- V# [3 a9 K3 R% |, ^6 ]紧螺栓或者螺母有什么关系么           
. ]) k  F3 x$ k5 a: A; ]Normally it will not matter whether the  bolt head or the nut is torqued.
# T) z! E/ r/ Q! O' Q* j一般来说不会。
This assumes that the bolt head and nut face are of the same diameter and the the contact  surfaces are the same (giving the same coefficient of friction).  
! Z7 |! J% Z. t7 B0 s# E+ I7 w7 k当然这是建立在螺栓和螺母的作用面尺寸相同的假设之下。(即摩擦系数相同)
If they are not then it does matter.
如果不是，紧谁就是有影响的。
* T7 u$ c5 k8 I0 Y9 C2 W' zSay the nut was flanged and the bolt head was not.
比如 螺母是带法兰的，而同时 螺栓不带。
  d0 S/ m" E6 t- ]If the tightening torque was determined assuming that the nut was to be tightened then if the bolt head was                     subsequently tightened instead then the bolt could be overloaded.
这时候，如果实际锁紧的扭矩是按 锁紧螺母需要的扭矩来决定的，而随后却用这个扭矩 去紧了螺栓，那么螺栓就过载了
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Typically 50% of the torque is used to overcome friction under  the tightening surface.
一般来说，50%的扭矩被用来克服锁紧面的摩擦

; ~. l7 ^# o1 V9 C7 [# a+ FHence a smaller friction radius will  result in more torque going into the thread of the bolt and  hence being over tightened.
( w+ y, Y- B$ `% |7 F6 `/ C- Y 因此，小的摩擦半径会导致 更多的扭矩给到螺栓上，以至其被锁的过紧了。                 
If the reverse was true - the torque determined  assuming that the bolt head was to be tightened then if the  nut was subsequently tightened - the bolt would be under tightened.   
反过来说也一样，如果在那种情况下（即上述螺母有法兰而螺丝没有）的实际锁紧的扭矩是按 锁紧螺栓需要的扭矩来决定的，而随后却用这个扭矩 去紧了螺母，那么螺栓就没锁紧。

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pengzhh

非常感谢，没有很好的理解————If the tightening torque was determined assuming that the nut was to be tightened then if the bolt head was                     subsequently tightened instead then the bolt could be overloaded.
7 v$ V2 z- I% c这时候，如果实际锁紧的扭矩是按 锁紧螺母需要的扭矩来决定的，而随后却用这个扭矩 去紧了螺栓，那么螺栓就过载了——————这句话，所以我纠结半天，现在好了，你翻译后我豁然开朗，谢谢

pengzhh

pengzhh 发表于 2014-3-26 15:31
非常感谢，没有很好的理解————If the tightening torque was determined assuming that the nut was to ...

哈哈哈，还是要谢谢你
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道士3141

这个貌似太专业了。。。
基本很少用扭力扳手，也就提不到用规定的扭矩去锁紧
- t9 i( J1 e& g/ ~' B- h9 P6 k不过这个想法真是不错，锁不同部件要求的锁紧力不一样，为省力，还是锁螺栓比较好是吗

pengzhh

道士3141 发表于 2014-3-27 15:25
" m* S8 b$ @3 `" j+ M! U1 |% B这个貌似太专业了。。。
1 T9 V5 h" M& {# V3 I基本很少用扭力扳手，也就提不到用规定的扭矩去锁紧
不过这个想法真是不错，锁不 ...

9 @" C, h7 r1 u& h' R% v9 }' a其实看一下螺栓连接的力分配图就会发现，摩擦面积的大小导致实际分配到螺杆的力不同，所以螺栓连接真正得到的扭距就不同。我们公司的所有拧紧 都是 按照扭距来得

道士3141

pengzhh 发表于 2014-3-27 15:35
其实看一下螺栓连接的力分配图就会发现，摩擦面积的大小导致实际分配到螺杆的力不同，所以螺栓连接真正得 ...

专业啊，以前外国公司也多次要求装配部门配备扭力扳手，按要求扭矩去扳，于是就去买了两个，但装配部并不热心用，技术部门也没安排专人去指导，几个领导可能商量了一下，终于还是不了了之了

dick3848

真是藏龙卧虎啊