Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
21CrMoV5-7 Washers (EN 10269 / 1.7709) Cr-Mo-V Q+T Bolting
21CrMoV5-7 washers are matched-grade load-distributing washers under 21CrMoV5-7 nuts and bolt heads, machined from EN 10269 1.7709 Cr-Mo-V Q+T bar stock. Used on every 21CrMoV5-7 bolted joint where the gasket flange or casing surface needs protection from nut-rotation friction marking.
Washers Designs and Variants
Three standard styles: flat round washer (DIN 125 / ISO 7089) for general use; large flat washer (DIN 9021 / ISO 7093) for oversized bearing area on softer-flange materials; hardened bearing washer (DIN 6916 / DIN 7349) for heavy-bolting service where the nut-side friction load is high.
Size Range
| Standard | Style | Bolt diameter range |
|---|---|---|
| DIN 125 / ISO 7089 | Flat round (standard) | M12 to M64 |
| DIN 9021 / ISO 7093 | Flat large (oversized OD) | M12 to M48 |
| DIN 6916 / DIN 7349 | Hardened bearing | M16 to M64 |
| ASME B18.21.1 hardened flat | Hardened flat inch | 1/2 inch to 2 1/2 inch |
Mechanical Properties (Q+T, EN 10269)
| Property | Value | Condition |
|---|---|---|
| Tensile (Rm) | 700 to 850 MPa | RT, Q+T |
| 0.2 percent proof stress (Rp0.2) | ≥550 MPa | RT, Q+T |
| Elongation A5 | ≥16 percent | RT, longitudinal |
| Charpy V impact (KV) | ≥63 J | 20 deg C |
| 0.2 percent proof at 500 deg C | ≥450 MPa | elevated-temp |
| Hardness | 210 to 250 HBW | Q+T |
Standards Anchor
Manufactured to EN 10269. Washer dimensions to DIN 125 / DIN 9021 / DIN 6916 (metric) or ASME B18.21.1 (Unified). Hardness 38 HRC minimum on hardened bearing washers, suitable for use under proof-load nut bolt-up without permanent deformation.
Companion Hardware
Matched-grade Cr-Mo-V companions ship from the same heat lot on call-out: 21CrMoV5-7 nuts, washers, threaded rod, stud bolts and round bar.
Applications
21CrMoV5-7 washers ship as matched-grade companion hardware on every stud bolt, hex bolt, heavy hex bolt, tap stud and body-bound stud project. Specified on all the same applications as the parent fastener: steam turbine, pressure vessel, heat exchanger and petrochem reactor service.
Inspection Documentation
Default delivery is EN 10204 type 3.1 mill test certificate with heat number, melt-shop pour record, chemistry to EN 10269 21CrMoV5-7, room-temperature tensile and 0.2 percent proof stress, elevated-temperature 0.2 percent proof at the design temperature, Charpy V impact at 20 deg C, hardness, full Q+T cycle chart and dimensional report tied to the heat lot. Type 3.2 with Lloyd's Register, DNV, BV, SGS or TUV witness inspection on call-out and standard practice on turbine and pressure-vessel procurement.
Frequently Asked Questions
Q. What is the hardness specification for a 21CrMoV5-7 hardened washer?
38 HRC minimum to DIN 6916 / DIN 7349 (metric) or ASME B18.21.1 hardened (Unified). The hardness specification ensures the washer does not deform under proof-load nut bolt-up.
Q. Do you supply washers in matched grade or can I use any hardened washer?
For high-cycle and elevated-temperature service, matched-grade 21CrMoV5-7 washers from the same heat lot as the stud are recommended to avoid relaxation differential between the washer and stud. For general bolting, ASME B18.21.1 hardened washers in any grade are acceptable.
Q. Can washers be supplied with a specific OD for oversize flange holes?
Yes. DIN 9021 large-flat washers have oversized OD per the DIN spec, and custom OD washers per the customer drawing ship on call-out.
Q. Do you supply Belleville (disc-spring) washers in 21CrMoV5-7?
Belleville washers ship from torqbolt.com separately in spring-steel grade. For 21CrMoV5-7-equivalent service-temperature Bellevilles, contact for project enquiry.
Related 21CrMoV5-7 Form Factors
Browse the full 21CrMoV5-7 form-factor range: Round Bar · Stud Bolts · Hex Bolts · Heavy Hex Bolts · Tap Studs · Body-Bound Studs · Anchor Bolts · U-Bolts · Threaded Rod · Nuts · Forgings. Back to the 21CrMoV5-7 Alloy Hub.
Satisfaction Survey
