BS ISO 965-4:1998

1   Scope This part of ISO 965 specifies deviations and limits of sizes for pitch and crest diameters for ISO general purpose metric external screw threads conforming to ISO 262 having a basic profile according to ISO 68-1. External screw threads according to this part of ISO 965 are intended to mate with internal screw threads tapped with tolerance position H or G after hot dip galvanizing. The limits of sizes for the tolerance quality specified are derived from tolerances specified in ISO 965-1 and the fundamental deviations according to the following formula:

 es 
 az  = −(300 + 20 P )



  
 
   where 
 
 
   
     
     
   
   
     
       
         es 
       
       is expressed in micrometres; 
     
     
       
         P 
       
       is expressed in millimetres. 
     
   
 

Products made with thread tolerances in accordance with this part of ISO 965 may show failure at lower ultimate tensile loads than those specified in ISO 898-1 due to reduction of the stress area. External screw threads with thread tolerances according to this part of ISO 965 must not be ma...