Composite Control Frame for Profile of Surface

 

Illustration: Profile of Surface control is applied generally for non regular shapes of castings, forgings or Pressed components. Here upper segment is depicting specification for compete pattern shifting of contour i.e. 0.5 mm Whole pattern can move in a band of 0.5 mm in any direction w.r.t datum A

Lower segment is controlling surface error within band of 0.1 mm. All high points and low points on the surface should lie between band of 0.1 mm. Both these phenomenon are illustrated in following figures.

Upper segment is also known as Pattern Locating Tolerance Zone (PLTZ) and Lower segment is known as Feature Relating Tolerance Zone (FRTZ)

PLTZ will have impact on wall thickness of subject casting, forging due to shift in above case and FRTZ will have impact on overall thickness and wall thickness due to high & low points on curvature (feature) which is within band of 0.1 mm

How to check flatness for composite control frame?

 

Illustration :  Upper segment of control frame is depicting total flatness specification ( 1mm) for overall complete area of part. Lower segment of control frame depicting flatness specification (0.3 mm) for any small part on the surface 35mmX 35mm on overall area. Modifier F represents free condition of part while inspection. i.e. Part to be kept on surface plate without any clamping load on it.

Inspection Procedure : 

- Nandkumar Walve, Corporate Trainer on Quality

  (nnwalve@gmail.com, 9820424387, https://ungliiart.com/TrainingDetails.php)