Volume 15 - Casting Part 10 pptx

Between two points in the same part of the mold; not affected by parting plane or core Specified dimension mm in. mm ≤ ≤ ±0.015 >25 >1 0.38 ± 0.002 mm/mm over 25 mm 0.015 ± 0.002 in./in. over 1 in. Flatness tolerance, as-cast Greatest dimension (a) mm in. mm Within 0.020 Each additional mm (in.) (b) 0.003 mm/mm 0.003 in./in. Across parting plane; A-type dimension plus below Projected area of casting, A 1 · A 3 = X mm 2 in. 2 mm X ≤ X ≤ ±0.010 X ≤ X ≤ ±0.015 X ≤ X ≤ ±0.020 X ≤ X ≤ ±0.025 161,000 < X ≤ 323,000 250 < X ≤ 500 ±0.76 ±0.030 Affected by moving parts; A-type dimension plus below Projected area of casting affected by moving part, A 3 · G = YA 1 · A 3 = X Metal core or mold mm 2 in. 2 mm in. mm Y ≤ Y ≤ ±0.015 Y ≤ Y ≤ ±0.025 Y ≤ Y ≤ ±0.030 Y ≤ Y ≤ ±0.040 Y ≤ Y ≤ ±0.060 Allowance for finish Maximum dimension, x Metal core or mold mm in. mm in. mm x x ≤ 0.060 x ≤ x ≤ 0.090 x ≤ x ≤ 0.120 x ≤ x ≤ 0.180 x > 610 x > 24, consult foundry . . . . . . . . . . . . Mod. Cast., Table 3 Typical linear tolerances in investment castings Dimension mm in. mm ±0.005 ±0.010 ±0.013 ±0.016 ±0.019 ±0.022 ±0.025 ±0.028 Maximum variation Maximum variation ±1.02 ±0.040 Precis. Met., Table 4 Typical tolerance relations for shell mold steel castings Dimension Across parting line mm in. ± mm ± in. ± mm 0.010 0.010 0.015 0.015 0.020 0.020 0.020 0.025 0.025 0.030 0.030 0.030 0.035 0.035 0.040 0.040 0.040 0.045 0.045 508 20 1.52 0.060 1.27 0.050 • Coordinate tolerancing • Geometric dimensioning and tolerancing Characteristic Symbols. Table 5 Symbols used in geometric dimensioning and tolerancing Type of feature Type of tolerance Characteristic Total Design of Ferrous Castings, Aluminum Casting Technology, Mod. Cast., Precis. Met., [...]... Trans AFS, Principles of Metal Casting, Metallographic Etching, Mod Cast., Mod Cast., Typical Microstructures of Cast Metals, Gray and Ductile Iron Castings Handbook, Physical and Engineering Properties of Cast Iron, Cast Met Res J., Trans AFS, Trans AFS, Melting Charge constituent -7 to 12 -1 0 to 20 -1 0 to 15 -1 5 to 25 -1 5 to 25 +Trace -1 0 to 20 -2 to 5 -2 to 5 -5 to 10 Sulfur +40 to 60 Inoculation... Free-cutting brasses, mold and core coatings, deliberate addition Tool steel ≤ 0.08 Solidification Forms carbides; promotes pearlite Steel scrap; some pig irons Graphite Morphology Matrix Structure α Phase Tensile strength, MPa (ksi) Elongation, % 75 200 Cementite 550 Table 2 Hardness ranges for various combinations of gray iron microstructures Microstructure 11 0-1 40 20 0-2 60 30 0-4 50 26 0-3 50 35 0-5 50... iron microstructures Microstructure 11 0-1 40 20 0-2 60 30 0-4 50 26 0-3 50 35 0-5 50 Austenite + graphite 14 0-1 60 Section Sensitivity Table 3 Minimum recommended section sizes for unalloyed gray irons Class Minimum section thickness mm in mm 0.06 0.12 0.17 0.17 0.28 0.33 60 25.4 1 10. 7 0.42 Table 4 Volume- to-surface-area ratios for bars and plates Cast form and size mm 0.12 0.12 0.12 0.29 0.29 0.28 0.48 0.48 0.47.. .Casting Design Handbook, Mod Met., Geo-Metrics II, • • • • • • Composition Type of Iron Total carbon, % Silicon, % CE = C+ CE = C+ Si Si + (Eq 1) P (Eq 2) Phosphorus Sulfur levels ≥ (Eq 3) Table 1 Effects, levels, and sources . Typical tolerance relations for shell mold steel castings Dimension Across parting line mm in. ± mm ± in. ± mm 0. 010 0. 010 0. 015 0. 015 0.020 0.020 0.020 0.025 0.025 0.030 0.030. by moving parts; A-type dimension plus below Projected area of casting affected by moving part, A 3 · G = YA 1 · A 3 = X Metal core or mold mm 2 in. 2 mm in. mm Y ≤ Y ≤ ±0. 015 Y ≤ Y ≤ ±0.025. points in the same part of the mold; not affected by parting plane or core Specified dimension mm in. mm ≤ ≤ ±0. 015 >25 >1 0.38 ± 0.002 mm/mm over 25 mm 0. 015 ± 0.002 in./in. over