G D & T And Co Ordinate Metrology

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Basic Knowledge of GD & T and latest Metro logical Instruments

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G D & T And Co Ordinate Metrology

  1. 1. G D & T and Co-ordinate Metrology Presented by: Mr. Nilay Thakore ( Sr.Ex) Unit 5, GCEDAD Dept. Email: [email_address] Ext: 338 Mobile: 9586281878
  2. 2. Index <ul><li>Introduction metrology </li></ul><ul><li>Methods of measurements </li></ul><ul><li>Uncertainty Sources </li></ul><ul><li>SWIPE Concept </li></ul><ul><li>Why use G D & T ? </li></ul><ul><li>G D & T Symbols </li></ul><ul><li>First principle: examples </li></ul><ul><li>Advance Metrological Instruments </li></ul><ul><li>CMM concept,construction,types,applications </li></ul>
  3. 3. 1. Introduction metrology <ul><li>The science/study of measurement is called metrology. </li></ul><ul><li>Generally a measurement is in two parts, a number and a unit. eg how long is it? 2 meters. </li></ul><ul><li>A measurement tells us about the property of something. </li></ul><ul><li>A measurement is always made using some instrument. </li></ul><ul><li>What is not a measurement ? Counting, comparing two string which is longer and test/experiment which leads to yes/no or pass/fail result. </li></ul>Sr. no. Physical quantity Name of the unit Symbol 1 Length Meter m 2 Time Second S 3 Mass Kilogram Kg 4 Temperature Kelvin K 5 Elec. Current Ampere A 6 Luminous intensity Candela Cd 7 Quantity of Substance Mole mol
  4. 4. <ul><li>“ when the need is defined & justified, weather we have it or not, we have to pay the price of both the conditions.” </li></ul>
  5. 5. 2. Methods of measurements
  6. 6. Measuring Instruments Classification:
  7. 7. 3. Uncertainty Sources <ul><li>Long term Reproducibility </li></ul><ul><li>Thermal expansion </li></ul><ul><li>Thermal gradient and coefficient of thermal expansion. </li></ul><ul><li>Elastic deformation </li></ul><ul><li>Probe contact deformation, compression of the artifact under their own weight. </li></ul><ul><li>Scale calibration </li></ul><ul><li>Uncertainty of artifact standard, linearity, scale thermal expansion. </li></ul><ul><li>Instrument Geometry </li></ul><ul><li>Abbe offset, cosine errors, obliquity etc. </li></ul><ul><li>Artifact effects </li></ul><ul><li>Flatness, Parallelism, Roundness etc. </li></ul>
  8. 8. 4. SWIPE Concept <ul><li>The 5 basic elements which define the accuracy of a measuring system are: </li></ul>
  9. 9. 5.Why use G D & T ? <ul><li>Allows max. Production Tolerance </li></ul><ul><li>Guarantees fits and interchangeability of mating parts and assemblies </li></ul><ul><li>Reduces potential for error in interpolation. </li></ul>
  10. 10. 6. G D & T Symbols
  11. 11. Datum <ul><li>A datum is a theoretically exact point, axis or plane from which the location or geometric characteristics of a part feature are established. </li></ul>
  12. 12. MMC & LMC <ul><li>When a part feature contains the maximum amount of material allowed within the specified size limit, it is said to be in its max. material condition. </li></ul><ul><li>- The MMC of an external feature is its upper size limit. </li></ul><ul><li>- The MMC of an internal feature is its lower size limit. </li></ul><ul><li>When a part feature contains the least amount of material allowed within the specified size limits it is said to be in its least material condition. </li></ul><ul><li>The LMC of an external feature is its lower size limit. </li></ul><ul><li>The LMC of an internal feature is its upper size limit. </li></ul>
  13. 13. Flatness A Flatness tolerance zone is the distance between two parallel planes, the part surface must lie between them.
  14. 14. Straightness A straightness tolerance is used to control the straightness of a surface or axis. It specifies how much the surface or axis is allowed to vary from the perfect straight line implied by the point.
  15. 15. Circularity <ul><li>Circularity refers to the roundness of a cylindrical ,cone shaped or spherical part feature at any given cross-section. </li></ul><ul><li>A circularity tolerance specifies how much the cross-section is allowed to vary from the perfect circularity implied by the point. </li></ul><ul><li>A circularity tolerance zone is bounded by two concentric circles. The surface of the cross-section must lie between them. </li></ul>
  16. 16. Cylindericity <ul><li>Cylindericity refers to the roundness of pins, shaft and other cylindrical features along their entire length. </li></ul><ul><li>A Cylindericity tolerance specifies how much the surface of the cylindrical feature is allowed to vary from the perfect cylinder implied by the drawing. </li></ul><ul><li>A Cylindericity tolerance zone is bounded by two concentric cylinders as specified distance apart The surface of the cylindrical feature must lie between them. </li></ul>
  17. 17. Perpendicularity <ul><li>Perpendicularity refers to a part surface, centre plane or axis that is 90 degree to a datum plane or axis. </li></ul>
  18. 18. Angularity <ul><li>Angularity refers to a part surface, centre plane or axis at specified angle other than 90 degree to a datum plane or axis. </li></ul>
  19. 19. Parallelism <ul><li>Parallelism refers to: </li></ul><ul><li>A surface or center plane that is an equal distance at all points from a datum plane. </li></ul><ul><li>An axis whose entire length is an equal distance from a datum plane or datum axis. </li></ul>
  20. 20. Profile Tolerances <ul><li>A Profile is a two dimensional outline of a part feature from top, side or front view. On a drawing, it is typically defined by basic dimensions in the form of sizes, radii, angles or arc. </li></ul><ul><li>There are two types of profile tolerances: </li></ul><ul><li>Profile of surface </li></ul><ul><li>Profile of a line </li></ul>
  21. 21. Circular Run out A Circular run out tolerance controls the relationship of individual circular elements of the part feature to a datum axis.
  22. 22. Total Run out A total run out tolerance controls the relationship of the entire feature surface to a datum axis.
  23. 23. Position Position refers to the theoretically exact location of the centre, axis or centre plane of a feature in relation to another feature or datum. A position tolerance specifies how much the centre, axis, or centre plane is allowed to vary from its theoretically exact location.
  24. 24. Concentricity Concentricity describes the relationship between the axes of two or more cylindrical features. Perfect concentricity exists when the axes coincide.
  25. 25. Symmetry A part feature that can be divided into two equal halves is described as symmetrical.
  26. 26. 7. First principle: examples
  27. 27. 8. Advance Metrological Instruments
  28. 28. Facility: Roundness Tester (RA-116) <ul><li>Roundness Tester (RA-116) </li></ul><ul><ul><li>Can Measure Critical Parameters as </li></ul></ul><ul><ul><ul><li>Roundness </li></ul></ul></ul><ul><ul><ul><li>Coaxiality </li></ul></ul></ul><ul><ul><ul><li>Concentricity </li></ul></ul></ul><ul><ul><ul><li>Flatness </li></ul></ul></ul><ul><ul><ul><li>Circular Runout (Radial and Axial) </li></ul></ul></ul><ul><ul><ul><li>Perpendicularity (Plane and Axis) </li></ul></ul></ul><ul><ul><ul><li>Thickness </li></ul></ul></ul><ul><ul><ul><li>Deviation </li></ul></ul></ul><ul><ul><ul><li>Parallelism </li></ul></ul></ul><ul><ul><li>Rotational and Axial Accuracy of 0.04 Microns </li></ul></ul><ul><ul><li>Max m Probing Dia 280mm </li></ul></ul><ul><ul><li>Max m Work piece Dia 440 mm </li></ul></ul><ul><ul><li>Table Loading Capacity 25 Kg </li></ul></ul><ul><ul><li>Probing Height 280mm </li></ul></ul><ul><ul><li>Probing Depth 100mm </li></ul></ul><ul><ul><li>Latest Software enables availability of Latest Calculation Methods, Filters for Measurement, Different UPR Settings </li></ul></ul>
  29. 29. Roundness Tester Applications
  30. 30. Facility: Surface Roughness Tester (SJ201) <ul><li>Surface Roughness Tester (SJ201) </li></ul><ul><ul><li>Can Measure Critical Parameters as </li></ul></ul><ul><ul><ul><li>Ra, Ry, Rz, Rt, Rp, Rq, Rv, Sm, S, Pc, R3Z, Mr(C) Rpk, Rvk, Rk, Mr1, Mr2, A1, A2, Vo, Rz1max etc </li></ul></ul></ul><ul><ul><li>Equipped with Universal Standards, Filters, Profiles, Cut Off Values , Speed etc </li></ul></ul><ul><ul><li>Easy to Carry and Handle; Can be kept directly on Job also </li></ul></ul><ul><ul><li>Can be easily mounted on Height Gauge or even Magnetic Stand </li></ul></ul><ul><ul><li>Different Detectors can measure Roughness of jobs with Small Holes, Grooves, Collars etc </li></ul></ul>Applications
  31. 31. Facility: Laser Scan Micrometer (LSM 503) <ul><li>Laser Scan Micrometer (LSM 503) </li></ul><ul><ul><li>Fast and Accurate Machine used for Diametrical and External Measurement </li></ul></ul><ul><ul><li>High Accuracy of up to 0.6 microns </li></ul></ul><ul><ul><li>Measurement range of 0.3 to 30mm </li></ul></ul><ul><ul><li>Resolution of 0.00002mm </li></ul></ul><ul><ul><li>Repeatability of ±0.11 Microns </li></ul></ul><ul><ul><li>Can take 3200 Scans Per Second </li></ul></ul>
  32. 32. Facility: Micro hardness Tester (HM112) <ul><li>Micro hardness Tester (HM112) </li></ul><ul><ul><li>Different Ranges of Loads available as </li></ul></ul><ul><ul><ul><li>10, 25, 50, 100, 200, 300, 500, 1000 Grams </li></ul></ul></ul><ul><ul><li>Objective lens of 50X and Occular Lens of 10X provide 500X of large magnification </li></ul></ul><ul><ul><li>Digital X-Y Table enables measurement of Case Depth </li></ul></ul>
  33. 33. Facility: Micro hardness Tester (HM112) <ul><li>Applications </li></ul>
  34. 34. Facility: Optical Profile Projector (PJA-3005) <ul><li>Optical Profile Projector (PJ-A3005) </li></ul><ul><ul><li>Magnifies small jobs for Inspection at small Edges, Corners </li></ul></ul><ul><ul><li>Angular Measurement of complete 360 0 </li></ul></ul><ul><ul><li>Up gradation to Software like MCOSMOS2D OR QM Data 200 can enable measurements of </li></ul></ul><ul><ul><ul><li>Radius </li></ul></ul></ul><ul><ul><ul><li>Center to Centre Distances </li></ul></ul></ul><ul><ul><ul><li>Performing Alignments </li></ul></ul></ul><ul><ul><ul><li>Relations between Parameters </li></ul></ul></ul>
  35. 35. Facility: Measuring Microscope (MF-1010) <ul><li>Measuring Microscope (MF-1010) </li></ul><ul><ul><li>Extended Version of Profile Projector </li></ul></ul><ul><ul><li>Can measure Linear Dimensions </li></ul></ul><ul><ul><li>Up gradation to Software like MCOSMOS2D OR QM Data 200 can enable measurements of </li></ul></ul><ul><ul><ul><li>Radius </li></ul></ul></ul><ul><ul><ul><li>Center to Centre Distances </li></ul></ul></ul><ul><ul><ul><li>Performing Alignments </li></ul></ul></ul><ul><ul><ul><li>Relations between Parameters </li></ul></ul></ul>
  36. 36. 9. CMM Co-ordinate measuring machines.
  37. 42. <ul><li>Types of CMM </li></ul><ul><li>Fixed CMM: </li></ul><ul><li>a.) Bridge type </li></ul><ul><li>b) Gantry Type </li></ul><ul><li>Accuracy Range:2.5+3L/1000 to 10+10L/1000 </li></ul><ul><li>Accuracy Range: 0.3+L/1000 to 5+L/200 </li></ul><ul><li>c) Horizontal Arm </li></ul><ul><li>Accuracy range:15+L/100 onwards </li></ul>
  38. 43. Trigger and High Accuracy Scanning sensors LSP-X3 Max. Stylus extension 360 mm LSP-X5 Max. Stylus extension 500 mm LSP S2/S4 Max. Stylus extension from 600 to 800 mm LSP-X1 Max. Stylus extension 220 mm Tesastar Manual Swivelling Tesastar I Manual Indexable Tesastar-m Motorized Indexable Leica T-Probe Walk around measuring probe Tesastar-mp Magnetic tip modules Stationary Portable Micro
  39. 44. Geometries and Applications <ul><li>As a consequence of that, depending on the type of geometry : </li></ul><ul><li>different Software are needed </li></ul><ul><li>different Sensors are needed </li></ul><ul><li>different Machine Structures are needed </li></ul>Simple Geometry Complex Geometry Sculptured Geometry
  40. 45. Software for all requirements PC-DMIS, General purpose & for sculptured Geometries Quindos Prismatic & Special geometries Chorus CAD PC-DMIS QUINDOS CogniTens CogniTens software package for white light measurement, sheet metal inspection, assembly analysis and reverse engineering ChorusCAD, /Surfer Sheet metal Stationary Portable Micro
  41. 46. <ul><li>Thank You… </li></ul><ul><li>Details of GD & T resources at z:(trashcan)/GDNT </li></ul>

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