RapidBolt
ASME PCC-1Through-Hardened Washers
Through-hardened washers for pressure-boundary bolted flange joints — Types 1, 4, 5, 6 and 7, 1/2″ to 4″ and 14 mm to 100 mm, matched to your stud bolts and certified to EN 10204 3.1.
Five washer types for flange assembly.
ASME PCC-1-2019 covers through-hardened washers for bolted flange joints in 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 depends on design, temperature requirements and the fastener material with which the washer is to be used.
Energy Materials Group supplies PCC-1 washers matched to your stud bolts and nuts, with material, hardness and dimensions confirmed against your specification at quotation.
| WASHER TYPE & MATERIAL | COMPATIBLE FASTENERS |
|---|---|
| Type 1Carbon steel | Steel fasteners such as Grade 2H, 4, or 7 steel nuts per ASME SA-194 |
| Type 4Low-alloy steel | Steel fasteners such as Grade 2H, 4, or 7 steel nuts per ASME SA-194 |
| Type 5Martensitic steel | Austenitic steel fasteners such as Grade 8 austenitic steel nuts per ASME SA-194 |
| Type 6Precipitation hardening steel | Austenitic steel fasteners such as Grade 8 nuts per ASME SA-194 |
| Type 7Austenitic steel | Austenitic steel fasteners such as Grade 8 nuts per ASME SA-194 in low-temperature applications |
ASME PCC-1 chemical limits
| 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 |
Type 4 low-alloy steel washers are manufactured from SAE number 4130 or 4140 steel listed in ASTM A829.
Type 5 martensitic steel washers are manufactured from UNS S41000 steel listed in ASTM A240.
Type 6 precipitation hardening steel washers are manufactured from UNS S17400 steel listed in ASTM A693.
Type 7 austenitic steel washers are manufactured from UNS S21800 steel listed in ASTM A276.
Hardness, tempering and temperature limits
| TYPE | HARDNESS RANGE (HRC) | MIN TEMPERING TEMPERATURE | SINGLE-USE LIMIT | REUSE LIMIT |
|---|---|---|---|---|
| Type 1 | 38–45 | 205°C (400°F) | 425°C (800°F) | 205°C (400°F) |
| Type 4 | 38–45 | 370°C (700°F) | 540°C (1,000°F) | 400°C (750°F) |
| Type 5 | 38–45 | 425°C (800°F) | 650°C (1,200°F) | 425°C (800°F) |
| Type 6 | 33–42 | 550°C (1,025°F) | 815°C (1,500°F) | 550°C (1,025°F) |
| Type 7 | 20–23 | Not applicable | Low-temperature applications | -45°C to -185°C (-50°F to -300°F) |
Washer dimensions — inch and metric
I.D. = inside diameter · O.D. = outside diameter · T = thickness
U.S. customary washers
| SIZE, IN. | O.D. MM | O.D. IN. | I.D. MM | I.D. IN. | T MM | T IN. |
|---|---|---|---|---|---|---|
| 1/2 | 27.0 | 1.063 | 14.3 | 0.563 | 3.2 | 0.125 |
| 5/8 | 33.4 | 1.313 | 17.5 | 0.688 | 4.0 | 0.156 |
| 3/4 | 38.1 | 1.500 | 20.7 | 0.813 | 4.8 | 0.188 |
| 7/8 | 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 |
| 1-1/8 | 54.8 | 2.156 | 30.2 | 1.188 | 6.4 | 0.250 |
| 1-1/4 | 60.3 | 2.375 | 33.4 | 1.313 | 6.4 | 0.250 |
| 1-3/8 | 65.9 | 2.593 | 36.5 | 1.438 | 6.4 | 0.250 |
| 1-1/2 | 71.4 | 2.812 | 39.7 | 1.563 | 6.4 | 0.250 |
| 1-5/8 | 77.8 | 3.062 | 42.9 | 1.688 | 6.4 | 0.250 |
| 1-3/4 | 82.6 | 3.250 | 46.1 | 1.813 | 6.4 | 0.250 |
| 1-7/8 | 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 |
| 2-1/4 | 104.8 | 4.125 | 60.3 | 2.375 | 6.4 | 0.250 |
| 2-1/2 | 115.9 | 4.563 | 66.7 | 2.625 | 6.4 | 0.250 |
| 2-3/4 | 127 | 5.000 | 73.0 | 2.875 | 6.4 | 0.250 |
| 3 | 138.1 | 5.438 | 79.4 | 3.125 | 6.4 | 0.250 |
| 3-1/4 | 149.2 | 5.875 | 85.7 | 3.375 | 6.4 | 0.250 |
| 3-1/2 | 160.4 | 6.313 | 92.1 | 3.625 | 6.4 | 0.250 |
| 3-3/4 | 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 |
Metric washers
| NOMINAL SIZE, MM | O.D., MM | 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 |
Metric sizes continue to 100 mm nominal; larger sizes confirmed per RFQ.
Tolerances for metric washers, mm
| CHARACTERISTIC | 14–16 MM | 20–27 MM | 30–42 MM | 45–76 MM | 82–100 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) | 0.25 | 0.30 | 0.40 | 0.50 | 0.80 |
| Concentricity, FIM | 0.3 | 0.5 | 0.5 | 0.5 | 0.5 |
| Burr height (max.) | 0.25 | 0.40 | 0.40 | 0.50 | 0.65 |
Concentricity measured as full indicator movement (FIM), inside diameter to outside diameter.
Coating specifications for PCC-1 bolting
Hot-dip galvanising (zinc coating) on iron and steel hardware
Electrodeposited coatings of zinc on iron and steel
Coatings of zinc mechanically deposited on iron and steel
Coatings of cadmium mechanically deposited
Electrodeposited coatings of cadmium
Electrodeposited coatings on mechanical fasteners, inch and metric
Zinc coating, hot-dip, for carbon and alloy steel bolts, screws, washers, nuts and special threaded fasteners
PTFE, Xylan, zinc-flake, hot-dip galvanised and cadmium finishes are supplied where specified — see our coated fasteners range. Coating selection is confirmed against your specification at quotation.
Traceable to the heat number.
Washers are marked with the manufacturer's identification and the applicable type or grade designation in accordance with ASME PCC-1, and are traceable to the mill heat number through the EN 10204 3.1 material test report supplied with every order. EN 10204 3.2 with third-party witness is available on request.
Hardness verification is reported on certification, and washers can be heat-number matched to companion stud bolts and nuts for full assembly traceability. Testing & certification
Where PCC-1 washers are specified
Matched stud bolts, nuts and alloys.
Questions engineers ask
What is an ASME PCC-1 through-hardened washer?
It is a flat washer hardened through its full thickness, described in Appendix M of ASME PCC-1, the guideline for assembling pressure-boundary bolted flange joints. It spreads bolt load evenly, protects the flange face and gives a smooth, low-friction bearing surface for the nut, improving the translation of torque input into bolt preload.
How is a PCC-1 washer different from an ASTM F436 washer?
ASTM F436 washers are general hardened washers mainly used in structural bolting. PCC-1 washers are dimensioned for flange spot faces and specified for controlled flange assembly, with defined types, hardness ranges, tolerances and tempering requirements. Always confirm dimensions and hardness against your own project specification.
What materials can you supply PCC-1 washers in?
Through-hardened carbon and low-alloy steel (Types 1 and 4) are most common. For corrosive service we also supply martensitic, precipitation-hardening and austenitic grades (Types 5, 6 and 7), plus stainless, duplex, super duplex and nickel alloys such as Inconel 625, 718 and C-276, matched to the stud bolt grade.
Can you supply PCC-1 washers with stud bolt kits?
Yes. Washers can be supplied as part of stud bolt and nut kits, heat-number matched and bagged and tagged per joint for shutdowns and turnarounds.
Do you supply PCC-1 washers outside Australia?
Yes. We supply Australia-wide and export to the USA, Canada, the North Sea, Papua New Guinea and Asia-Pacific, with certification and Incoterms confirmed at quotation.
Send the flange schedule or washer list — we will quote type, size and grade against your specification.
Tables on this page summarise ASME PCC-1-2019 Appendix M for reference. The licensed standard governs — confirm all requirements against your purchase specification. EMG does not supply copies of the standard.