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Limits, Fits & Tolerances
 

Limits, Fits & Tolerances

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This presentation would help you in understanding Limits, Fits & Tolerances used in various engineering designs and drawings.

This presentation would help you in understanding Limits, Fits & Tolerances used in various engineering designs and drawings.

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  • Very good presentation. Basics are clear. Can you send it to me on my mail please if possible. pvasu60@gmail.com
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    Limits, Fits & Tolerances Limits, Fits & Tolerances Presentation Transcript

      • Contents
      • Introduction
      • Fits
      • Tolerancing
      • Tolerances
      • Modifiers
    • Guide to GD&T– Variants Still Allowed GEOMETRIC DIMENSIONING & TOLERANCING ANSI Y14.5M – R1988 STANDARD
      • History:
      • Since 1900
      • Widely used during WW2
      • Automotive Industry
      • Standardisation 1982
    • Engg. Intent – Dimension &Tolerance GD&T
      • Define the GEOMETRY of the part precisely
      • Communicate the product Function & Design Relationship
      • Process Variation
      Whys?
    • Dimensioning
      • Defines the SIZE of a feature
      • Defines the LOCATION of a feature
      Dimension Basic Size Function defines Tolerance, Tolerance defines Process Size Limit
      • 
      •  
      • 
    • Hole Based System Fits Transition Fit
      • Press – For Non Fe – Allows removal
      • Drive - For Fe Medium , Non Fe Light – Allows removal
      • Force/Shrink – High Interference
      H6/p5 , H7/p6 H6/r5 , H7/r6 , H6/s5 , H7 / s6 H6/u5 , H7/u6
      • Clearance – Very Small Clearance
      • True - Zero Clearance , Slight Interference tolerated
      • Interference – Slight Interference
      H6/h5 , H6/h6 H7/h6 ,H7/h7 H8/h7 , H8/h8 H9/h8 , H9 / h9 H11/h9 , H11/h11 H8/b9 , H8/a9 H6/j5 , H7/j6 , H8 /j7 H6/k5 , H7/k6 , H6/k7 H6 /m5 ,H7/m6 , H8/m7 H6/g5 , H7/g6 H6/f65 , H7/f7 , H7/e7 , H8 / e8 H8/d8 , H8/d9 Hole Zero Line Shaft Shaft Shaft
      • Stationary parts
      • Location – Precision / Close /Normal/Loose
      • Assembly – Slack / Positional Fit
      • Precision – Small Clearance - Location
      • Close Running - Shafts
      • Normal Running – Large Shafts , Brgs
      • Loose Running – Medium clearance Pulleys,PBs
      • Slack/Positional – Large Clearance - Not used
      Interference Fit Shaft Hole Zero Line Location & Assembly Fit Shaft Hole Zero Line Running & Sliding Fit Shaft Hole Zero Line
    • Tolerancing
      • Bilateral Tolerances :
      • 20 +/-0.018
      • 20 +0.013 / - 0.015
      • Unilateral tolerances :
      • 20 +0.018 /0
      • 20 –0.012/-0.016
    • Tolerance stack – Proper dimensioning key Tolerance Stack up
      • Chain Method:
      • Point to Point
      • Shifting reference
      • Cumulative effect on tolerance
      • Base Line Method:
      • Single Reference
      • Reduced cumulative effect on tolerance
      • Direct Method:(Combination)
      • Direct Reference
      • Least cumulative effect on tolerance
      15 +/-0.2 10 +/-0.2 10 +/-0.2 8 +/-0.2 28 +/-0.6 43 +/-0.2 33 +/-0.2 15 +/-0.2 25 +/-0.2 28 +/-0.4 33 +/-0.2 15 +/-0.2 25 +/-0.2 28 +/-0.4
    • Function defines Tolerance, Tolerance defines Process Tolerances Form
      • Limits deviation of an individual parameter from it geometrically ideal form
      Profile
      • Same as Form
      Position
      • Limits the deviation of the relative position of two or more parameters
      Process
      • Limits the deviation of a “ Fundamental”parameter ( Like Temp, Pressure Time
    • 5 Types Types Form Straightness Flatness Circularity Cylindricity Profile Profile of a Line Profile of a Surface Position Orientation Location Angularity Perpendicularity Parallelism True Position Concentricity Symmetry Run Out Circular Run - Out Total Run - out
    • Always look at the mating part Modifiers
      • “ Modifiers”
      • Modify the specified tolerance
      • Influence the tolerance zone
      • Defined by the function
      M L RFS Common Modifiers MMC - Maximum Material Condition LMC – Least Material Condition S Regardless of Feature Size Reference S SR R Radius Spherical Radius Spherical Diameter
    • Notations Reference Datum Datum Symbol Axis as Datum Surface Line as Datum Toleranced Element/Parameter 0.02 A Tolerance Symbol Tolerance Symbol Datum ( When required) A 25 Nominal Dimension
    • Feature Control Frame Position Tolerance Zone Symbol Shape of Tolerance Zone Size of Tolerance Zone Primary Datum Secondary Datum Tertiary Datum Material Condition Modifier Secondary Datum Material Condition Modifier B A 0.2 M C M
    • Function drives Modifiers Modifiers E=mC 2 E=cM 2
    • Tolerance Zone does not Change Modifiers
      • RFS – R egardless of F eature S ize
      • The tolerance value is unaltered “Regardless of Size” of toleranced parts
      • Application
      • Holes with Zero Clearance
      • Shaft /Hole combination for Interference fits
    • Process Control Size Vs Position LMC
      • LMC – Least Material Condition - SIZE conditions
      • The Feature of size : It has the Least Material within the size limits specified
      • Rules:
      • External Features – Subtract the tolerance
      • Internal Features – Add the tolerance
      25 20 12 +0.2 / - 0.1 B A 0.2 C L C B A
    • Process Control Size Boss Vs Hole LMC 25 +2 B A 1 C L B A 0.2 C L LMC – Boss & Hole C B 12 - 0.5 A 75 60 25 12 Boss Tol. Zone 1 Hole Tol. Zone 0.2
    • Bonus Zone Modifiers
      • MMC – Maximum Material Condition - SIZE conditions
      • The Feature of size : It has the Maximum Material within the size limits specified
      • Rules:
      • External Features – Add the tolerance
      • Internal Features – Subtract the tolerance
      • Application
      • Clearance holes ( Mounting/Assembly)
      Eg; Position Tolerance of the hole increase as the hole size increases
    • Classic Case- Bell Crank & Sleeve Modifiers at MMC A A 0.02 M 25 0.00/-0.018 18 0.00 /-0.013 A A 0.02 M 25 0 .02/0.00 18 0.013/0.00
    • Modifiers MMC On Hole M Datum A 0.2 M Hole 60 10 +0.2 / 0 20 +0.1 / 0 A 0.4
    • Modifiers at MMC On Datum M Datum Hole A 0.2 M 60 10 +0.2 / 0 20 +0.1 / 0 A 0.3
    • Modifiers MMC On Hole & Datum M Datum 0.2 M Hole 60 10 +0.2 / 0 20 +0.1 / 0 A A M 0.6
    • Datum Ref. Frame is Theoretical Datum
      • Origin from which a Location of a feature is defined
      • Origin from which the shape of a feature is defined
      • Theoretical “Perfect geometry” ( Point , Line or Plane)
    • Manufacturing & Inspection w.r.t.specified datum Datum External Datum Datum Simulator Datum Simulator Datum Simulator Internal Datum A A A
    • Controls Form of Cylindrical/Conical Surfaces- Applies to Entire Surface DEFINITION : Straightness is a condition where the surface or an axis of an element is a straight line.
      • TOLERANCE ZONE : Straightness tolerance
              • Specifies a tolerance zone within which the considered surface/axis or derived median line must lie.
              • Straightness tolerance is applied in the view where the parameter to be controlled is represented by a straight line.
      REFERENCE TO DATUMS : No reference datum . MMC, LMC, RFS TO FEATURE : Applicable if the tolerance applies to the axis or center plane of a feature or size. Not applicable if the toleranced feature is a surface. MMC, LMC, RFS TO DATUMS : No datum reference . PERFECT FORM AT MMC : Applicable when the tolerance is applied to a surface. "Perfect from at MMC not required" may be specified. Especially useful when the part is subject to small deformations under its own weight or internal stresses. STRAIGHTNESS 0.21
    •       Straightness: Applied to the Surface Cylinder
      • The surface must lie within the specified tolerance zone
      • The dimension of perfect form at MMC (1.510).
      • Each longitudinal element must lie within two parallel lines 0.002 apart.
      STRAIGHTNESS 0.21
    • Neck Bow Barrel STRAIGHTNESS 0.21
    • Cylinder Liner Tier 2 STRAIGHTNESS 0.21
    • Note effect of Size Tolerance
      • Straightness tolerance is
      • Applied in the view where the elements to be controlled are represented by a straight line.
      • Tolerance zone is constrained into the plane of projection of the view where it is called.
      • For each linear element on the surface, the tolerance zone of straightness may be oriented differently, as long as it stays in the correct plane.
      STRAIGHTNESS 0.21
    • Direction is in the View Straightness: Applied to a plane surface Measurement Direction STRAIGHTNESS 0.21
    • Combined Straightness “is” Flatness The tol. notation is attached to a leader line to the surface or to an extension line of the surface. STRAIGHTNESS 0.21
    • Controls Form deviation of plane surfaces – Qualifies surface for primary datum FLATNESS DEFINITION Flatness is the condition of a surface having all the elements of which in one plane. TOLERANCE ZONE The flatness tolerance specifies a tolerance zone defined by two parallel planes within which the surface must lie. REFERENCE TO DATUMS No reference datum. MMC, LMC, RFS TO FEATURE Not applicable. MMC, LMC, RFS TO DATUMS Not applicable.No reference datum PERFECT FORM AT MMC Where the surface under consideration has a size dimension, the flatness tolerance must be less than the size tolerance. Flatness 0.05 0.05/100
      • The surface must lie between two parallel planes 0.25 apart.
      • The surface must be within the specified limits of size.
      Flatness 0.05
    • Flatness – Primary Datum/Seat/Sealing face Flatness 0.05
    • Datum , Seat Definition Flatness 0.05
    • Defines Datum DEFINITION Circularity is a condition of a surface of revolution where a.   (For a Cylindrical/Round feature other than a sphere,) all points of the surface intersected by any plane perpendicular to the axis are equidistant from that axis; b.   For a sphere, all points of the surface intersected by any plane passing through a common center are equidistant from that center. TOLERANCE ZONE A circularity tolerance specifies a tolerance zone bounded by two concentric circles within which each circular element of the surface must lie, and applies independently at any plane. REFERENCE TO DATUMS No reference datum. MMC, LMC, RFS TO FEATURE Not applicable. MMC, LMC, RFS TO DATUMS Not applicable.No reference datum PERFECT FORM AT MMC The circularity tolerance must be less than the size tolerance, except for parts subject to free state variation. CIRCULARITY/ROUNDNESS 0.05
    • The tolerance zone of circularity is expressed as the radial difference between two concentric circles The circularity tolerance applies at each circular section of the diameter independently CIRCULARITY/ROUNDNESS 0.05
    • CIRCULARITY/ROUNDNESS 0.05
    • “ Combined effect” of Straightness & Roundness DEFINITION Cylindricity is a condition of a surface of revolution in which all points of the surface are equidistant from a common axis. TOLERANCE ZONE A Cylindricity tolerance specifies a tolerance zone bounded by two concentric cylinders within which the surface must lie. REFERENCE TO DATUMS No reference datum. MMC, LMC, RFS TO FEATURE Not applicable. MMC, LMC, RFS TO DATUMS Not applicable.No reference datum PERFECT FORM AT MMC Applicable. Cylindricity tolerances cannot violate the maximum boundary of perfect form at MMC of the associated size tolerance. Application Functional applications that require a true cylinder such as rotating shaft journal and bearing diameters, pistons and piston bores. Also used to qualify datum diameters. Used only when the size tolerance does not provide appropriate form control. Cylindricity 0.03
      • The tolerance zone of Cylindricity is made of two concentric cylinders.
      • The leader line from the tol. notation may be shown in either view.
      Cylindricity 0.03
    • Cylindricity 0.03
    • DEFINITION A profile is the outline of an object in a given plane. The profile tolerance specifies a uniform boundary along the true profile within which the elements of the line must lie. It is used to control form or combinations of size, form, orientation, and location. TOLERANCE ZONE The tolerance zone established by the profile of a line tolerance is two-dimensional, extending along the length of the considered feature. This applies to the profiles of parts having a varying cross section, such as the tapered wing of an aircraft, or to random cross sections of parts where it is not desired to control the entire surface of the feature as a single entity. REFERENCE TO DATUMS In most cases, profile of line tolerance requires reference to datum in order to provide proper orientation, location, or both, of the profile. With profile of a line tolerance, datum may be used under some circumstances but would not be used when the only requirement is the profile shape taken cross section by cross section. An example is the shape of a continuous extrusion. MMC, LMC, RFS TO FEATURE The specified tolerance can only apply on an RFS basis. MMC, LMC, RFS TO DATUMS The datum reference can only apply on an RFS basis. Application Typically used to control profiles of parts having a varying cross section. Line Profile 0.1 0.1 A
    • Effect of Size Form Tolerance Line Profile
      • Each line element of the surface between points C and D, at any cross section, must
      • Lie between two profile boundaries 0.16 apart in relation to datum planes A and B.
      • Be within the specified limits of size.
    • DEFINITION A profile is the outline of an object in a given plane. The profile tolerance specifies a uniform boundary along the true profile within witch the elements of the line must lie. It is used to control form or combinations of size, form, orientation, and location. TOLERANCE ZONE The tolerance zone established by the profile of a surface tolerance is three-dimensional, extending along the length and width (or circumference) of the considered feature or features. REFERENCE TO DATUMS Profile of surface tolerance requires reference to datum in order to provide proper orientation, location, or both, of the profile. With profile of a line tolerance, datum may be used in some circumstances but would not be used when the only requirement is the profile shape. MMC, LMC, RFS TO FEATURE The specified tolerance can only apply on an RFS basis. MMC, LMC, RFS TO DATUMS The datum reference can only apply on an RFS basis. TYPICAL USE Typically used to control parts with a surface of revolution, or castings with surfaces defined by profile tolerances . Surface Profile 0.05 A 0.05
    • Note Effect of Size Tolerance
      • The surface between points D and E must
      • Lie between two profile boundaries 0.25 apart.
      • Perpendicular to datum plane A,
      • Equally disposed about the true profile and positioned with respect to datum planes B and C.
      Surface Profile 0.05
    • Gen 1 Bell Crank Surface Profile 0.05
      • Each surface must lie between two common parallel planes 0.08 apart.
      • Both surfaces must be within the specified limits of size.
      Surface Profile 0.05
    • Position Tolerance
    • DEFINITION
      • Defines a zone within which the
      • Center
      • Axis
      • Center plane
      • of feature of size is permitted to vary from a true (theoretically exact) position
      TOLERANCE ZONE A position tolerance specifies one of the following: 1.  A tolerance zone defined by two parallel planes related to specified datum. 2.  A cylindrical tolerance zone related to specified datum, within which the axis of the considered feature must lie. 3.  A spherical tolerance zone related to specified datum, within which the center of the considered feature must lie. REFERENCE TO DATUMS Obligatory with the PLTZF. Optional with the FRTZF. MMC, LMC, RFS TO FEATURE Based functional requirements MMC, LMC or RFS, appropriate modifier can be applied on position tolerance. MMC, LMC, RFS TO DATUMS Based on functional requirements MMC, LMC or RFS, appropriate modifier can be applied on the datum axis. Application of MMC, LMC and RFS is limited to features subject to variations in size. Hole Position 0.2
    • ZERO POSITIONAL TOLERANCE AT MMC Where no variations in position is allowed at the MMC limit of size, the feature control frame contains a zero for the tolerance zone size, modified by the MMC symbol. PATTERN-LOCATING TOLERANCE ZONE FRAMEWORK (PLTZF) Where composite controls are used, the upper segment is referred to as the pattern-locating control. The PLTZF is located from specified datum by basic dimensions. It specifies the larger positional tolerance for the location of the pattern of features as a group. FEATURE-RELATING TOLERANCE ZONE FRAMEWORK (FRTZF) The lower segment is referred to as the features-locating control. It governs the smaller positional tolerance for each feature within the pattern (feature-to-feature relationship). Where datum references are not specified in the lower segment of the composite feature control frame, the FRTZF is free to bee located and oriented within the boundaries established and governed by the PLTZF. If datum are specified in the lower segment, they govern the orientation of the FRTZF relative to the PLTZF. TYPICAL USE Typically used to control the location of features in assembly. B A 0.2 C M B A 0.2 C M B A 0.2 C M M 0.2 M Hole Position 0.2
    • The PLTZF (Ø0.8) is located from datum (ABC) by basic dimensions. It specifies the larger positional tolerance for the location of the pattern of holes as a group. The lower segment governs the smaller positional tolerance (Ø0.25) (feature-to-feature relationship) within the pattern . The FRTZF is free to locate and orient within the boundaries established and governed by the PLTZF. Datum A governs the orientation (perpendicularity) of the FRTZF . Pattern Location - PLTZF Feature Realtion - FRTZF Hole Position 0.2
    • Co- Axial Holes Pattern Location - PLTZF Feature Relation Location - FRTZF Hole Position 0.2
    • Gen 1 Bell Crank
      • C-D Defines X-Axis
      • E Defines Y-Axis
      • B Defines Perpendicularity
      Hole Position 0.2
    • Hole Position 0.2
    • DEFINITION The median points of all diametrically opposed elements of a surface of revolution lie on the same axis (or center point) of a datum feature. TOLERANCE ZONE A concentricity tolerance is a Cylindrical (or spherical) tolerance zone whose axis (or center point) coincides with the axis (or center point) of the datum feature(s). REFERENCE TO DATUMS One datum feature (axis or center point). APPLICABILITY OF MMC, LMC, RFS TO FEATURE The specified tolerance can only apply on an RFS basis. APPLICABILITY OF MMC, LMC, RFS TO DATUMS The datum reference can only apply on an RFS basis. TYPICAL USE Typically used to control ……….. Concentricity 0.04 A
    • Position Tolerance Concentricity
      • Regardless of feature size, ( within size tolerance)
      • All median points of diametrically opposed elements of the slot must lie within Ø0.4 cylindrical tolerance zone.
      • The axis of the tolerance zone coincides with the axis of datum feature A.
    • Use Either as Datum Position Tolerance Concentricity
    • Use a Spigot Locator Position Tolerance Concentricity
    • DEFINITION The median points of all opposed or correspondingly-located elements of two or more feature surface lie in the same axis or center plane of a datum feature. TOLERANCE ZONE A symmetry tolerance is two parallel planes whose axis (or center plane) coincides with the axis (or center plane) of the datum feature. REFERENCE TO DATUMS One datum feature (center plane). APPLICABILITY OF MMC, LMC, RFS TO FEATURE The specified tolerance can only apply on an RFS basis. APPLICABILITY OF MMC, LMC, RFS TO DATUMS The datum reference can only apply on an RFS basis. Symmetry 0.05 A
      • Regardless of feature size,( within Size Tolerance) all median points of opposed elements of the slot must
      • Lie between two parallel planes 0.8 apart.
      • The two parallel planes being equally disposed about datum plane A
      Symmetry 0.05 A
    • Gen1 Bell Crank Symmetry 0.05 A
    • Position Tolerance Angularity DEFINITION Condition of a surface, center plane, or axis at a specified angle from a datum plane or axis. TOLERANCE ZONE A angularity tolerance specifies one of the following: 1.       A tolerance zone defined by two parallel planes at the specified basic angle from one or more datum planes or axis, within which the surface or center plane of the considered feature must lie. 2.       A tolerance zone defined by two parallel planes at the specified basic angle from one or more datum planes or axis, within which the axis ot the considered feature must lie. 3.       A cylindrical tolerance zone at the specified basic angle from one or more datum planes or axis, within which the axis of the considered feature must lie. 4.       A tolerance zone defined by two parallel lines at the specified basic angle from one or more datum planes or axis, within which the line element of the surface must lie. REFERENCE TO DATUMS One or more datum features. Relation to more than one datum feature is specified to stabilize the tolerance zone in more then one direction. MMC, LMC, RFS TO FEATURE Based on functional requirements MMC, LMC or RFS, appropriate modifier can be applied on angularity tolerance. Application of MMC, LMC and RFS is limited to features subject to variations in size. MMC, LMC, RFS TO DATUMS If the functional requirements of some applications require MMC, LMC or RFS, appropriate modifier can be applied on the datum axis. Application of MMC, LMC and RFS is limited to features subject to variations in size. PERFECT ANGULARITY AT MMC Where no variations of angularity at MMC size limit of feature, the feature control frame contains a zero for the tolerance, modified by the symbol for MMC. TYPICAL USE Typically used to control orientation between planes surfaces.
    • Position Tolerance Angularity
      • Regardless of feature size,the feature axis must
      • Lie within a 0.2 diameter cylindrical zone inclined 60º to datum plane A.
      • Be within the specified tolerance of location.
      Angularity : Applied to Cylindrical Feature
    • Position Tolerance Angularity
      • The surface must
      • Lie between two parallel planes 0.4 mm apart which are inclined at 30º to datum A.
      • Be within the specified limits of size.
      Angularity : Applied to Plane Surface
    • Position Tolerance Perpendicularity DEFINITION Condition of a surface, center plane, or axis at a right angle to a datum plane or axis. TOLERANCE ZONE 1.       A tolerance zone defined by tow parallel planes perpendicular to a datum plane or axis, within which the surface or center plane of the considered feature must lie. 2.       A tolerance zone defined by two parallel planes perpendicular to a datum axis, within which the axis ot the considered feature must lie. 3.       A cylindrical tolerance zone perpendicular to a datum plane, within which the axis of the considered feature must lie. 4.       A tolerance zone defined by two parallel lines perpendicular to a datum plane or axis, within which the line element of the surface must lie. REFERENCE TO DATUMS One or more datum features. Relation to more than one datum feature is specified to stabilize the tolerance zone in more then one direction. MMC, LMC, RFS TO FEATURE Based on the functional requirement MMC, LMC or RFS, appropriate modifier can be applied on perpendicularity tolerance. Application of MMC, LMC and RFS is limited to features subject to variations in size. MMC, LMC, RFS TO DATUMS Based on functional requirements MMC, LMC or RFS, appropriate modifier can be applied on the datum axis. Application of MMC, LMC and RFS is limited to features subject to variations in size.. PERFECT PEPENDICULARITY AT MMC Where no variations of perpendicularity at MMC size limit of feature, the feature control frame contains a zero for the tolerance, modified by the symbol for MMC.
    • Perpendicularity
      • The surface must lie between two parallel planes 0.12 mm apart which are perpendicular to datum plane.
      • The surface must be within the specified limits of size.
      Perpendicularity : Applied to Plane Surface
    • Perpendicularity : Applied to Cylindrical Feature
      • Regardless of feature size,( within Size Tolerance limits the feature axis must
      • Lie within a 0.2 mm diameter cylindrical zone perpendicular to datum axis A.
      • Be within the specified tolerance of location.
      Perpendicularity
    •  
    • 100
    • Position Tolerance Parallelism DEFINITION Condition of a surface, center plane, equidistant at all points from a datum plane; or axis and equidistant along its length from one or more datum planes or a datum axis. TOLERANCE ZONE A parallelism tolerance specifies one of the following: 1.       A tolerance zone defined by tow parallel planes parallel to a datum plane or axis, within which the surface or center plane of the considered feature must lie. 2.       A tolerance zone defined by two parallel planes parallel to a datum axis, within which the axis ot the considered feature must lie. 3.       A cylindrical tolerance zone parallel to a datum plane, within which the axis of the considered feature must lie. 4.       A tolerance zone defined by two parallel lines parallel to a datum plane or axis, within which the line element of the surface must lie. REFERENCE TO DATUMS One or more datum features. Relation to more than one datum feature is specified to stabilize the tolerance zone in more then one direction. MMC, LMC, RFS TO FEATURE Based on functional requirements MMC, LMC or RFS, appropriate modifier can be applied on parallelism tolerance. Application of MMC, LMC and RFS is limited to features subject to variations in size. MMC, LMC, RFS TO DATUMS Based on functional requirements MMC, LMC or RFS, appropriate modifier can be applied on the datum axis. Application of MMC, LMC and RFS is limited to features subject to variations in size.. PERFECT PARALLELISM AT MMC Where no variations of parallelism at MMC size limit of feature, the feature control frame contains a zero for the tolerance, modified by the symbol for MMC.
    • Position Tolerance Parallelism
      • The surface must
      • Lie between two parallel planes 0.12 mm apart which are parallel to datum plane.
      • Be within the specified limits of size
      Parallelism : Applied to Plane Surface
    • Position Tolerance Parallelism
    • Parallelism : Applied to Cylindrical Feature
      • Regardless of feature size,the feature axis must
      • Lie within a 0.2 mm diameter cylindrical zone parallel to datum axis A.
      • Be within the specified tolerance of location.
      Position Tolerance Parallelism
    • Position Tolerance Run-out DEFINITION Runout is a composite tolerance used to control the functional relationship of one or more features of a part to a datum axis. The types of features controlled by runout tolerance include those surfaces constructed around a datum axis and those constructed at right angles to a datum axis. TOLERANCE ZONE Each considered feature must be within its runout tolerance when the part is rotated about the datum axis. The tolerance specified for a controlled surface is the total tolerance or full indicator movement (FIM). REFERENCE TO DATUMS One or more datum features. Relation to more than one datum feature is specified to stabilize the tolerance zone in more then one direction. APPLICABILITY OF MMC, LMC, RFS TO FEATURE The specified tolerance can only apply on an RFS basis. APPLICABILITY OF MMC, LMC, RFS TO DATUMS The specified datum can only apply on an RFS basis. TYPICAL USE Typically used to control circularity and concentricity simultaneously.
    • Position Tolerance Run-out Run-Out: Circular / Radial Run- Out At any measuring position, each circular element of these surfaces must be within the specified run-out tolerance (0.02 mm FIM) when the part is rotated 360º about the datum axis with the indicator fixed in a position normal to the true geometric shape.
    • Run-Out: (Circular / Radial) Total Indicated Reading The entire surface must lie with the specified total run-out tolerance zone (0.02 mm FIM) When the part is rotated 360º about the datum axis with the indicator placed at every location along the surface in a position normal to the true geometric shape without reset of the indicator
    • Run-Out: (Circular / Radial) Total Indicated Reading
    • Run-Out: Face- Total Indicated Reading- Example
    •  
    • Building Blocks
    • Template Types M Straightness Flatness Circularity Cylindricity Profile of a Line Profile of a Surface Angularity Perpendicularity Parallelism Concentricity True Position Symmetry Circular Run - Out Total Run - out 25 +2 B A 1 C L B A 0.2 C L