Fixing Stripped Threads With Helicoils

In  this segment we'll look at identifying  thread pitch and size thread pitch and  size are very important to anyone who  uses fittings or any threaded components  here's what you'll need to perform the  procedures shown in this brief video a  caliper a pitch gauge a thread  identification guide let's take a look  threads have peaks and valleys referred  to as crests and roots the surface  between the crest and the root is called  a flank tapered threads.

Which may also  be referred to as dynamic threads are  designed to seal as the flanks of the  mating threads are drawn together a  thread sealant is required to fill in  the gaps between the crests and roots to  prevent system fluids from penetrating  the connection straight threads which  may also be referred to as parallel  threads are not designed to seal they  must rely on other factors such as a  gasket o ring or some kind of metal to  metal contact to create a leak tight  seal the first step to identifying the  thread size and pitch is to determine.

Whether the thread is tapered or  parallel tapered threads are at an angle  in relation to the center line while  parallel threads are parallel to the  centerline use a caliper to measure the  nominal male or female thread press to  crest diameter on the first fourth  and last full threads if the diameter  increases on a male end or decreases on  the female end the thread is tapered if  all the diameters are the same the  thread is a straight thread now use the  caliper to measure the nominal male or  female thread diameter from crest to  crest for a tapered thread measure the  fourth or fifth full thread for a  parallel thread measure any full thread.

The next step is to determine the thread  pitch use a pitch gauge and check the  thread against each form until you find  a match some fractional and metric  thread forms are very similar so this  may take a little time the final step is  to determine the thread standard take  the information you have gathered the  thread category the nominal diameter and  the thread pitch and use a thread  identification...