We are getting more people asking about welding nuts to parts.  We are finding that the majority of these people do not realize that there are specialty electrodes already made for this application. 

    Again I will refer to the CMW catalog for tables and pictures concerning this style of tip.

    The nut electrodes fall into two catagories:  self-piloting  and non-piloting (spring loaded). 

    The drawings below illustrate these electrodes, but I will try to describe it also in case the drawing is confusing.  This electrode is made of copper with an elkonite facing on the weld surface.  This facing increases the tip life since it is more wear resistant than copper.  The self piloting nut electrode has an insulated pin that the nut fits over for locating it (see figure 1).  The non-piloting nut electrode has a spring loaded insulated pin to locate the nut, but the pin pushes down when the upper electrode comes down. (see figure 2). The pin returns to the upright position after the weld is complete.

                                      
                      
                      figure 1                                               figure 2
                                    
   
    The electrode number is determined by the diameter of the electrode (O.D.), the nut you are going to use, and whether you want the solid pin or the spring loaded pin. You will find the table below for both these styles.

 
                                                       Spring loaded or non-piloting


   
    A special external cooling chamber can also be added for additional cooling of the electrode.  These cooling chambers fit over the OD of the electrode. These are not mandatory, but can be usefull.

          


    The nut electrode is usually the lower electrode.  The recommended upper electrode is called a "back up electrode".  I would recommend using a elkonite back up electrode for the upper electrode when you have an elkonite lower electrode.  The diameter of the back up electrode should match the diameter of the stud electrode.  I would recommend:

          stud electrode      back up electrode
             16-3764-xxxx          632050 or 832050
        16-3774-xxxx           632050  or 83205
        16- 3765-xxxx        16-1342
        16-3775 - xxxx          16-1342
        16-3766-xxxx            16-1343         
                                                                                                                           Kranitz Corporation
                                                                                                                           phone 262-242-4410
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