ASME PCC-1 Specifications
Through-Hardened Steel Washers for Pressure Boundary Bolted Flange Joints
Scope
ASME PCC-1-2019 Through-hardened washers for bolted flange joints covered within the scope of this Guideline are manufactured with a size range of 14 mm through 100 mm and 1/2 Inch through 4 Inch. These washers are used for pressure-containing flanges with bolts or studs and nuts where improved translation of torque input into bolt preload is required by providing a smooth and low friction bearing surface for the nut. Five washer types are covered, designated Types 1, 4, 5, 6 and 7. Selection will depend upon design, temperature requirements, and the fastener material for which the washer is to be used.
| Washer Type and Material | Compatible Fasteners |
|---|---|
| ASME PCC-1 Type 1, Carbon Steel | Steel fasteners such as Grade 2H, 4, or 7 steel nuts per ASME SA-194 |
| ASME PCC-1 Type 4, Low-alloy Steel | Steel fasteners such as Grade 2H, 4, or 7 steel nuts per ASME SA-194 |
| ASME PCC-1 Type 5, Martensitic Steel | Austenitic steel fasteners such as Grade 8 austenitic steel nuts per ASME SA-194 |
| ASME PCC-1 Type 6, Precipitation Hardening Steel | Austenitic steel fasteners such as Grade 8 nuts per ASME SA-194 |
| ASME PCC-1 Type 7, Austenitic Steel | Austenitic steel fasteners such as Grade 8 nuts per ASME SA-194 in low-temperature applications |
Related Specifications of ASME PCC-1
ASME PCC-1 Chemical requirements
| Element | Type 1 | Type 4 | Type 5 | Type 6 | Type 7 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| P, max % | 0.050 | 0.040 | 0.040 | 0.040 | 0.060 | ||||||
| S, max % | 0.060 | 0.050 | 0.030 | 0.030 | 0.030 | ||||||
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ASME PCC-1 Mechanical Properties
| Type | Hardness Range | Min Tempering Temperature | Temperature Limits | |
|---|---|---|---|---|
| HRC | Single-Use | Reuse | ||
| ASME PCC-1 Type 1 | 38-45 | 205°C (400°F) | 425°C (800°F) | 205°C (400°F) |
| ASME PCC-1 Type 4 | 38-45 | 370°C (700°F) | 540°C (1,000°F) | 400°C (750°F) |
| ASME PCC-1 Type 5 | 38-45 | 425°C (800°F) | 650°C (1,200°F) | 425°C (800°F) |
| ASME PCC-1 Type 6 | 33-42 | 550°C (1,025°F) | 815°C (1,500°F) | 550°C (1,025°F) |
| ASME PCC-1 Type 7 | 20-23 | Not applicable | Low-temperature applications | -45°C to -185°C (-50°F to -300°F) |
ASME PCC-1 Dimensional Requirements
Dimensional Requirements for Metric Washers
| Nominal Size, mm | Outside Diameter, O.D., mm | Inside Diameter, I.D., mm | Thickness, T, mm |
|---|---|---|---|
| 14 | 28 | 15 | 3 |
| 16 | 30 | 17 | 4 |
| 20 | 37 | 21 | 5 |
| 24 | 44 | 25 | 6 |
| 27 | 50 | 28 | 6 |
| 30 | 56 | 31 | 6 |
| 33 | 60 | 34 | 6 |
| 36 | 66 | 37 | 6 |
| 39 | 72 | 42 | 6 |
| 42 | 78 | 45 | 6 |
| 45 | 85 | 48 | 6 |
| 48 | 92 | 52 | 6 |
| 52 | 98 | 56 | 6 |
| 56 | 105 | 62 | 6 |
| 64 | 115 | 70 | 6 |
| 70 | 125 | 76 | 6 |
| 76 | 135 | 82 | 6 |
| 82 | 145 | 88 | 6 |
| 90 | 160 | 96 | 6 |
| 95 | 165 | 101 | 6 |
| 100 | 175 | 107 | 6 |
Dimensional Requirements for U.S. Customary Washers
| Nominal Size, in. | Outside Diameter, O.D. | Inside Diameter, I.D | Thickness,T | |||
|---|---|---|---|---|---|---|
| mm | in. | mm | in. | mm | in. | |
| ½ | 27.0 | 1.063 | 14.3 | 0.563 | 3.2 | 0.125 |
| ⅝ | 33.4 | 1.313 | 17.5 | 0.688 | 4.0 | 0.156 |
| ¾ | 38.1 | 1.500 | 20.7 | 0.813 | 4.8 | 0.188 |
| ⅞ | 43.6 | 1.718 | 23.8 | 0.938 | 5.6 | 0.219 |
| 1 | 50.0 | 1.968 | 27.0 | 1.063 | 6.4 | 0.250 |
| 1⅛ | 54.8 | 2.156 | 30.2 | 1.188 | 6.4 | 0.250 |
| 1¼ | 60.3 | 2.375 | 33.4 | 1.313 | 6.4 | 0.250 |
| 1⅜ | 65.9 | 2.593 | 36.5 | 1.438 | 6.4 | 0.250 |
| 1½ | 71.4 | 2.812 | 39.7 | 1.563 | 6.4 | 0.250 |
| 1⅝ | 77.8 | 3.062 | 42.9 | 1.688 | 6.4 | 0.250 |
| 1¾ | 82.6 | 3.250 | 46.1 | 1.813 | 6.4 | 0.250 |
| 1⅞ | 87.3 | 3.438 | 49.2 | 1.938 | 6.4 | 0.250 |
| 2 | 93.7 | 3.688 | 54.0 | 2.125 | 6.4 | 0.250 |
| 2¼ | 104.8 | 4.125 | 60.3 | 2.375 | 6.4 | 0.250 |
| 2½ | 115.9 | 4.563 | 66.7 | 2.625 | 6.4 | 0.250 |
| 2¾ | 127 | 5.000 | 73.0 | 2.875 | 6.4 | 0.250 |
| 3 | 138.1 | 5.438 | 79.4 | 3.125 | 6.4 | 0.250 |
| 3¼ | 149.2 | 5.875 | 85.7 | 3.375 | 6.4 | 0.250 |
| 3½ | 160.4 | 6.313 | 92.1 | 3.625 | 6.4 | 0.250 |
| 3¾ | 173.1 | 6.813 | 98.4 | 3.875 | 6.4 | 0.250 |
| 4 | 182.6 | 7.188 | 104.8 | 4.125 | 6.4 | 0.250 |
ASME PCC-1 Dimensional Tolerances
Dimensional Tolerances for Metric Washers
| Dimensional Characteristics | Tolerance, mm, for Nominal Size of | ||||
|---|---|---|---|---|---|
| 14 mm Through 16 mm | 20 mm Through 27 mm | 30 mm Through 42 mm | 45 mm Through 76 mm | 82 mm Through 100 mm | |
| Inside diameter, I.D. | -0, +0.4 | -0, +0.5 | -0, +0.6 | -0, +0.7 | -0, +0.9 |
| Outside diameter, O.D. | -1.3, +0 | -1.6, +0 | -1.9, +0 | -2.2, +0 | -2.5, +0 |
| Thickness, T | ±0.15 | ±0.20 | ±0.20 | ±0.20 | ±0.20 |
| Flatness (max. deviation from straight edge placed on cut side) | 0.25 | 0.30 | 0.40 | 0.50 | 0.80 |
| Concentricity, FIM [Note (1)] (inside diameter to outside diameter) | 0.3 | 0.5 | 0.5 | 0.5 | 0.5 |
| Burr height (max. projection above adjacent washer surface) | 0.25 | 0.40 | 0.40 | 0.50 | 0.65 |
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Dimensional Tolerances for U.S. Customary Washers
| Dimensional Characteristics | Tolerance for Nominal Size of | |||||||
|---|---|---|---|---|---|---|---|---|
| <1 in. | 1 in. Through 1½ in. | >1½ in. Through 3 in. | >3 in. | |||||
| mm | in. | mm | in. | mm | in. | mm | in. | |
| Inside diameter, I.D. | -0, +0.81 | -0, +0.032 | -0, +0.81 | -0, +0.032 | -0, +1.60 | -0, +0.063 | -0, +1.60 | -0, +0.063 |
| Outside diameter, O.D. | ±0.81 | ±0.032 | ±0.81 | ±0.032 | ±1.60 | ±0.063 | ±1.60 | ±0.063 |
| Thickness, T | ±0.13 | ±0.005 | ±0.13 | ±0.005 | ±0.13 | ±0.005 | ±0.13 | ±0.005 |
| Flatness (max. deviation from straight edge placed on cut side) | 0.25 | 0.010 | 0.38 | 0.015 | 0.51 | 0.020 | 0.81 | 0.032 |
| Concentricity, FIM [Note (1)] (inside diameter to outside diameter) | 0.81 | 0.032 | 0.81 | 0.032 | 1.60 | 0.063 | 1.60 | 0.063 |
| Burr height (max. projection above adjacent washer surface) | 0.25 | 0.010 | 0.38 | 0.015 | 0.51 | 0.020 | 0.64 | 0.025 |
ASME PCC-1 Bolting Surface Treatment Specifications
A153/A153M
Specification for Hot Dip Galvanising (Zinc Coating) on Iron and Steel Hardware
B633 Specification for Electrodeposited Coatings of Zinc on Iron and Steel
B695
Specification for Coatings of Zinc Mechanically Deposited on Iron and Steel
B696 Specification for Coatings of Cadmium Mechanically Deposited
B766 Specification for
Electrodeposited Coatings of Cadmium
F1941/F1941M
Specification for Electrodeposited Coatings on Mechanical Fasteners, Inch and Metric
F2329/F2329M
Specification for Zinc Coating, Hot-Dip, Requirements for Application to Carbon and Alloy Steel
Bolts, Screws, Washers, Nuts, and Special Threaded Fasteners
ASME PCC-1 Bolting Components Marking
Product Shall be Marked with our manufacturing trade mark "TorqBolt" or "TB" along with the
designated Grade.
Grade and manufacturer’s identification symbols shall be applied to one end of studs and to the heads of bolts
and screws of all sizes. (If the available area is inadequate, the grade symbol may be marked on one end and
the manufacturer’s identification symbol marked on the other end.) For bolts and screws smaller than 1⁄4 in.
[6 mm] in diameter and studs smaller than 3⁄8 in. [10 mm] in diameter and for 1⁄4 in. [6 mm] in diameter studs
requiring more than a total of three symbols, the marking shall be a matter of agreement between the purchaser
and the manufacturer.
| Type | Type Marking |
|---|---|
| ASME PCC-1 Type 1 | TB 1 |
| ASME PCC-1 Type 4 | TB 4 |
| ASME PCC-1 Type 5 | TB 5 |
| ASME PCC-1 Type 6 | TB 6 |
| ASME PCC-1 Type 7 | TB 7 |
ASME Dimensional Standards
B18.31.2
Imperial Continious Thread, Double End Reduced & Full Body Studs
B18.31.3 Threaded Rods (Inch Series)
B16.5
Imperial Full Thread Stud Bolts
B16.5
Metric Full Thread Stud Bolts
B18.2.1 Imperial Square and Hex
Bolts and Screws
B18.3
Imperial Hexagon Socket and Spline Socket Screws
ASME PCC-1 Bolting Certifications
- EN 10204 3.1
- EN 10204 3.2
- PED 2014/68/EC
- MERKBLATT AD 2000 W2/W7/W10
- API 20 E BSL 1/ BSL 2
- NACE MR 0175
- NACE MR 0103