Product Description
DIN 125-B round flat washer (form B), 31 x 56 x 4 mm, Article number 125B31. Property class / material: steel 140 hv, surface finish plain. Round Flat Washer manufactured to DIN 125. Standard parts to the same standard, property class, dimensions and surface finish are interchangeable between manufacturers; confirm the controlling standard revision, any class-society or application approval, and the mating thread before substitution. Applications: load distribution and locking under bolt heads and nuts in machine building, structural steel, plant maintenance and marine outfitting.
Technical Specifications
- Standard
- DIN 125
- Standard description
- B
- Property class / grade
- HV140
- Class (detailed)
- HV140
- Material hardness
- HV140
- Surface treatment
- Plain (no plating)
- Surface treatment code
- PLAIN
- Diameter
- 30 mm
- Inner diameter
- 31 mm
- Outer diameter
- 56 mm
- Thickness
- 4 mm
- Article number
- 125B31
- Category
- Washers / Plain Washers
Standards & Compliance
- Standard
- DIN 125
- Size / Series
- 31 x 56 x 4 mm
- Material
- Steel 140 HV
- HS Code
- 731822
Product Documentation
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Technical guides
Catalogue entry last verified: 2026-09-30. A manufacturer datasheet is attached to this entry — confirm application-critical values against it.
Frequently asked questions
- Where can I buy 125B31?
- 125B31 can be ordered from cballast.com as a Bufab catalogue item: request a quotation on this page or email sales@cballast.com, and the order ships worldwide.
- What is the manufacturer part number for this Bufab product?
- The manufacturer part number is 125B31.
- What is the HS code for 125B31?
- The customs tariff (HS) code for 125B31 is 731822.
- Who manufactures 125B31?
- 125B31 is a Bufab product in the C-Parts range.
- Is a datasheet available for 125B31?
- Yes — the 125B31 datasheet can be viewed and downloaded on this page.
- What is the minimum order quantity for 125B31?
- The minimum order quantity is 1.
- Is 125B31 available?
- Yes — 125B31 is available to order: fulfilment is from supplier stock in cBallast's European network, dispatched directly from the warehouse to the customer, with the exact lead time stated in the quotation (reply within 24 hours).