Forged and rolled rings up to 6,000 mm
Seamless rolled and open-die pierced rings from 20 kg to 25 t — for bearing seats, flanged joints and turbine components.
Ring rolling is the most economical process for rotationally symmetric rings above roughly 300 mm diameter. A pierced preform is progressively expanded in diameter between the main roll and the mandrel while the wall thickness decreases. The grain flow ends up oriented tangentially — exactly in the direction of the later hoop stress. A seamless rolled ring is therefore stronger than one turned from solid or welded from plate.
INTEG supplies forged rings with outside diameters from 300 to 6,000 mm and piece weights from 20 kg to 25 tonnes. Small batches and single pieces are explicitly possible, because ring rolling needs no part-specific tooling. Rectangular sections are standard; profiled rings with contoured cross-sections are available on request.
Technical data
| Outside diameter | 300 – 6,000 mm |
|---|---|
| Height | 50 – 1,500 mm |
| Wall thickness | 30 – 500 mm |
| Piece weight | 20 kg – 25 t |
| Process | Ring rolling (seamless), open-die pierced rings |
| Cross-section | rectangular; profiled on request |
| Testing | UT to EN 10228-3, MT to EN 10228-1, mechanical properties |
These are typical manufacturing ranges within our supplier network. Larger dimensions and special materials on request — send us your drawing.
Materials
- P355NH (1.0565)
- 16Mo3 (1.5415)
- 42CrMo4 (1.7225)
- 34CrNiMo6 (1.6582)
- 1.4541 / 321
- 1.4462 duplex
Manufacturing and quality assurance
- Piercing and expanding the preform, then rolling to final contour with tangential grain flow.
- Heat treatment of the complete ring — normalising, quenching and tempering or solution annealing depending on grade and duty.
- Ultrasonic testing to EN 10228-3 through the full section; magnetic particle or dye penetrant testing of surfaces.
- Mechanical properties taken from a prolongation ring forged with the part, tested in tangential and radial direction where required.
- Machining from a rough contour through to a finish-turned ring with bearing seats and bolt pattern.
Typical applications
- Bearing races for large slewing bearings
- Turbine and generator rings
- Flange rings for pressure vessels
- Rings for wind energy installations
- Gear rim blanks and slewing rings
- Pipeline connection rings
Frequently asked questions
What is the advantage of a seamless rolled ring?
The grain flow follows the circumference and therefore the main load direction. There is no weld seam as a weak point and no interrupted grain as in a ring turned from solid. Material usage also drops sharply — turning from solid means machining away the entire centre.
What quantity makes ring rolling economical?
One piece. Ring rolling needs no part-specific tooling, so there are no tooling costs. That makes the process attractive for one-offs and spare parts as well as for series.
What tolerances do rolled rings achieve?
As rolled, dimensions carry a few millimetres of allowance depending on size. For bearing seats and sealing faces we supply the rings pre-machined or finish-machined to the tolerances stated in your drawing.
Are profiled ring sections possible?
Yes — with contoured rolls, L-, T- and other profiled sections can be rolled. This saves machining but requires a profile tool, which pays off quickly from medium quantities.
What is the lead time for forged rings?
Pre-machined, typically 6 to 8 weeks from release. Large rings above 4 tonnes run 12 to 14 weeks. For recurring rings we set up call-off agreements, which shortens delivery considerably.
Request a quote for Forged rings
Send us your drawing or specification. You get feedback on feasibility, material selection and an indicative price — from engineers, not from a call centre.
Send enquiry