Quality, Design & Technical Assistance

WTI Inserts conform to all recognised national and international thread and Wire Thread Insert standards.

WTI work with your team to ensure the best design & quality solution

Our experience in a wide and diverse range of industries, including aerospace, automotive and electronics, means we understand your requirements and processes, which is why we provide technical assistance to production engineers so that optimum installation efficiency can be achieved and maintained.

Strength of insert a beneficial condition for product design

Because of their mechanical advantage, when correctly installed, WTI inserts can easily achieve threaded assemblies where tensile failure of the male thread should occur before insert failure. This is a beneficial condition for product design, since threaded assemblies can be more accurately calculated around known limits - i.e. bolt yield etc.

The tables listed below provide a basis for such design: by simply plotting pre-determined values for bolt ultimate tensile against shearing strength of parent material, read the resultant length of insert required to obtain the desired condition.

 

Shear Strength of Parent Matl
MPa
Bolt / Male Thread Minimum Ultimate Tensile MPa
390 490 590 790 980 1180 1370
70 2D 2.5D 3D        
100 1.5D 1.5D 2D 2.5D 3D    
150 1D 1.5D 1.5D 2D 2.5D 3D 3D
200 1D 1D 1D 1.5D 2D 2D 2.5D
250 1D 1D 1D 1.5D 1.5D 2D 2D
300 1D 1D 1D 1D 1.5D 1.5D 2D
350 1D 1D 1D 1D 1D 1.5D 1.5D

 

Shear Strength of Parent Matl
16sF/ft²
Bolt / Male Thread Minimum Ultimate Tensile Tons F/In²
24 34 43 48 56 59 71 80 98
70 2D 2.5D 3D 3D          
100 1.5D 1.5D 2D 2.5D 2.5D 3D 3D    
140 1D 1.5D 1.5D 2D 2D 2D 2.5D 3D  
170 1D 1D 1.5D 1.5D 1.5D 2D 2D 2.5D 2.5D
210 1D 1D 1D 1.5D 1.5D 1.5D 2D 2D 2.5D
280 1D 1D 1D 1D 1D 1.5D 1.5D 1.5D 2D
350 1D 1D 1D 1D 1D 1D 1D 1.5D 1.5D

Note: For intermediate values use the next higher column for bolt tensile and the next lower column for parent material strength.

The above figures assume male thread or bolt is fully engaged along the entire length of insert. The above charts are for general guidance only - for specific applications, WTI Engineering can provide more accurate advice and support.

 


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