CAST & FORGED PARTS - SHOP RUN TOLERANCES 1. SCOPE 1.1 Scape. ‘This specification establishes gencral requirements and shop-run toler- ances for cast and forged pat. 1.1.1 Classification This specification contains the following classes. Unless ‘otherwise specified, the requirements herein apply to all classes. CLASS A: Castings and Forgings with Run-out and Draft Allowance CLASS B: Castings with Run-out Controlled by Contour Tolerance and no Draft Allowance 1.2 Definitions. For the purposes of this specification, the following definitions shall apply. For definitions of flaws sce Interpretation of Drawing Specification PITF3. Airfoil Surface - Any surface designed to obtain a reaction from the relative move- ‘ment of ait. For blades and vanes, this is generally the portion above the platform and below the tip shroud as applicable. Flowpath - The controlled air passage for the flow of air through a gas turbine engine. Significant Area sequently machined ¥y area of the casting not designated on the drawing as “‘sub- 2. APPLICABLE DOCUMENTS 2.1 There are no applicable documents. (See 4.1)3. REQUIREMENTS. 3.1 Applicability. The requirements of this specification apply to all surfaces and features of the part except those identified by the symbol * yX™* or those which have spe cifically defined tolerances for cleanup, draft, lash, or other characteristics covered by this specification. This symbol identifies machined surfaces for which the drawing may specify machining stock allowance. The requirements of this specification then apply to the cast ‘or forged surface established by the machining stock allowance. When this specification is referenced with the specification for Machined Features, the applicability is as follows: (2) Surfaces and features indicated by the symbol “x shall conform to the form and postional tolerances of the Machined Features specification regardless of hhow they are produced (b) Obvious machined features such as spot faces, chamfers, screw threads, and drilled and reamed holes, shall conform to the requirements of the Machined Features specification. 3.1.1 Stock Allowance, If the casting or forging source is responsible for fishing the par deseribed by the next higher drawing level, variations in sock allowance. on indicted surfaces may be made to suit he requirments ofits particular method of assem bly or machining, provided thatthe finl part that it provides completely conforms to drawing requiresens, 3.2 Worknanchip. Castings and forgings shall be clean and free fron internal and exteinal discontinuities uhieh exceed specified linits. Fluorescent paneteant Sndications’causod by positive wetal (erg. rolled edges of gate sitness) in nach stock areas are acceptable. Flavs devected in machine stock areas of blade & wane castings by fluorescent penetrant of visual inspection are sceepeabie provided the depth Gf the indfeation 1s decerained to be less than the specified mehining sllorance, 32.1 Process Limitations, Welding, plugging, impregnating, peening, or other proc cesses shall not be used on castings and forgings except as permitted by specific érawing notes. Surface conditioning, using standard shop practice for removal of surface indica- tions, is permissible within drawing dimensional limits 33 Deleted 33.1 Deleted. 34 Castings. 3.4.1 Cleanup. Evidence of gates, risers, parting lines (masking lines), fins, chills, in- process welds, core support welds, mismatch, wax welds, and core loeators shall be trimmed and blended to the casting contour to the values shown in Table T Cleanup Allowance.Table T- Casting Cleanup Allowance SURFACESNoT supsecT To | _ SURFACES sUBIECTTO SUBSEQUENT MACHINING. | SUBSEQUENT MACHINING pox amon amrons |ROWPATH [ALLoTimRs| ALL SURFACES ‘WITNESS ALLOWANCI ANAM AND cares i auLomuzes sexs +000 +005 | +000 “+0000 “0030 PARTING LINES com oe | Sasa a ‘om cutis MISMATCH PLES <0 OMe MAX | aocsmax | ooromax ono max Car MAX WAX WELD EVIDENCE] nor pexvarTen] +0010 | room Tana ‘oom | ‘ours Zoo CORELOCATOR Foo aoe | saa a0 | ‘EVIDENCE coo om | “ae ‘0 34.1.1 Rolled Edges. Rolled edges on gate and riser witnesses or parting lines as a result Of removal operations are permitted provided they are continuous in nature and firmly attached. See Figure 1 Figure 1 - Rolled Edges rolled edge 3.4.12 Surfice Roughness, Surface roughness requirements specified in the drawing title block are to be verified by sight and feel comparison to a commercially available surface roughness specimen. Unless otherwise specified, surface roughness requirements do not apply to surfaces which will be subsequently machined. 3.4.2 Draft. CLASS A: Draft shall be applied as additional material to the dimen- sions shown on the drawing except when a negative draft is specified. Neither inside nor ‘outside draft angles shall exceed 3 degrees for sand castings and 0.5 degrees for invest- ‘ment castings. These values may be exceeded to match draft when required as shown in Figure 2a,CLASS B: For surfaces not designated as a datum surface, draft angles must be contained within dimensional limits. For all surfaces, draft angles shall not exceed 3 degrees for sand castings and 1 degree for investment castings, except to match draft when required as shown in Figure 2a, or when additional drat is required for internal features controlled by preformed ceramic cores Normal Draft Angle ‘On Long Side Paring tie Match Draft to Compensate For ‘Unequal Die Depths Figure 2a - Matching Draft 34.3 Rumout CLASS A: The circular run-out of all cast diameters constructed about a common axis shall not exceed 0.005 inch FIM for each inch of diameter with respect to all other diameters shown concentric to the same axis. If a datum axis is es- tablished by the drawing for such a group of diameters, the tolerances shall be in elation to the datum axis, CLASS B: Run-out allowance does not apply. All points on the surface of a feature dimensioned as a toleranced radius or diameter shown concentric about an axis established by the datum system must be within a tolerance zone established. by two concentric circles, one at the minimum radius and the other at the maximum radius, whose centers are coincident with the established axis. See Figure 2b. DRAWING CALLOUT INTERPRETATION ep : oR MUST CONFORM TO. PITFIN CL-B Figure 2b - Concentric Tolerance Zone34.4 Deleted. 34.5 Visual Flaws. The following paragraphs provide the acceptability limits for ‘visual surface flaws on castings. These limits apply to all as-cast surfaces. Verification of the requirements may be made by any practical means including visual standards or aids 345.1 Acceptability Limits, (@) Nicks and Scratches. Table II provides the acceptability limits for nicks and scratches with discemable depth. Connecting flaws of this type are to be interpreted as a single flaw. ‘These limits apply ‘only to the depth and length of the flaws and there are no limits for quantity and spacing of the flaws. Visual flaws of 0.001 inch or less in depth are considered uninterpretable. ‘Table Il - Acceptability Limits for Nicks and Scratches on Castings DEPTH (i) LENGTH. [ EDGE AND FILLET RADI Not Allowed Not Allowed AIRFOIL ‘ALL OTHER (0.003 or less (050 max SURFACES | _ amrom SURFACES ‘over 0.003 not allowed Not allowed, as 10.005 or less 150 max, ALL “AREA over 0.005 19 0.015 0.50 max. Rimeices ‘over 0.015 not allowed Not allowed NON-SIGNIFICANT ‘Any depth and length provded they do not en Violate drawing dimensional limits, () Depth of flaw applies relative wo surounding cast surface oto te resin igh mel (©) Dents. Dents are acceptable provided: (1) They do not exceed 0.010 inch in depth (2) The width is at least 10 times the depth (2) They blend smoothly with adjacent surfaces: © Discoloration. Discoloration due to processing is acceptable, if not disallowed by other specifications. Discoloration due to other causes is not acceptable,@ High Metal. High metal is not allowed on Airfoil Surfaces. For all other surfaces, high meta is not to exceed 0.005 inch above sur- rounding cast surface. (e) Contamination. None permitted. All heat-treated parts shall be ‘Slean and Tree from foreign naterial prior to any heat. treatment (©) Gperacion, and all cavities must be cleared of all chemical agents used Qiring mamtacture inmediately following each such processing. ( Superfictal Imperfections” Superficial imperfections of no measur able depth such as burish marks and evidence of contact with ‘gages and fixtures are not considered detrimental and are permit- ted on any cast surface, (@) Flow Lines. Flow lines shall not exceed 0.010 inch in depth. (8) Sink, Sink is alowed within drawing dimensional tolerance. 35. Eongings. CLASS A: 3.5.1. Elash, All flash shall be trimmed to the requirements shown in Figure 3a unless the drawing specifies “CLOSE TRIM FLASH”. Then the flash shall be trimmed to the requirements shown in Figure 36. no evidence of this radius permitted on cither side trim line shall have oN parting Tine a surface roughness equal to or beter than the "as forged” drawing ‘mismatch mismatch requirements (a) Normal Flash (b) Close Flash - When Specified On Drawing Figure 3 - Flash 35.2 Draft, Draft shall be applied as additional material to the dimensions shown on the drawing. Draft angles on forgings shall conform to the values shown in ‘Table TI, ‘These values may be exceeded to match draft when required, as shown in Figure 2a, Table II - Forging Draft Angles INSIDE HOLES FORGING PROCESS OUTSIDE DRAFT. AND DEPRESSIONS Flammer 10° Max 13 Max Upset 5° Max 8° Max |3.5.3 Run-out, The circular run-out of all forged diameters constructed about a ‘common axis shall not exceed 0.03 FIM for diameters on the same side of the parting line. ‘When the diameters are on opposite sides of the parting line, the specified mis-match tolerance is in addition to the run-out tolerance. If a datom axis is established by the drawing for such a group of diameters, the tolerance shall be in relation to the datum axis, 3.6 Dimensioning - Castings and Forgings. 3.6.1 Datums. Generally, dimensions that define cast and forged parts originate from three mutually perpendicular datum planes. When these planes are designated in ‘order of use; ie, primary, secondary, and tertiary, the part shall be mounted on the primary datum surface first, on the secondary datum surface second, and (When required) fon the tertiary datum surface third 3.6.1.1 Datum Targets. Normally, the primary datum surface will rest on three high points, the secondary datum surface on two high points, and the tertisry datum surface on one high point. If the drawing, however, designates specific datum points rather than just datum surfaces, the designated points shall be used, 3.6.1.1. Datum Target Surfacc, The area indicated for a datum point on a part shall be free of any surface flaws or interruptions resulting from shop processes. If itis necessary to use the area for gates, risers, flash, etc, the excess shall be carefully removed and blended with the surface to assure repetitive uniformity between parts 3.6.1.2 Datum Related Dimensions. CLASS B: Dimensions originating from datum features established by datum targets apply from the datum and not the datum feature. 3.7 Dimensions. CLASS A: Dimensions apply only at the intersection of sur- faces except when a surface identified as a datum plane is established by indicated datum target points. See Figures 4, 5, and 6. 3.8 Acceptability, Acceptability limits as defined within this specification apply independently of dimensional limits. Thickness dimensions Intersecting point to which apply 10 smallest thickness dimensions apply Height CLASS A: Figure 4 - Intersections of SurfacesDRAWING CALLOUT INTERPRETATION TT Ti CLASS A; Figure 5 - Application of Dimensions DRAWING CALLOUT INTERPRETATION, L “The L | DATUM DATUM DATUM. POINT, POINT, POINT CLASS A: Figure 6 - Dimension, Datum Point Relationship 4, NOTES 4.1 Conjunct Spccifications. This specification is to be used in conjunction with Interpretation of Drawing Specification P1TF3 which defines terms and establishes general requirements, PITF3 is invoked by separate drawing note and is not a subsidiary document to this specification. At times on a combination casting - machining or forging-machining drawing, specification PITF9, Machined Features, is specified in conjunction with this specification. For such cases, 3.1 of this specification establishes the order of provedence.