S346/U-D Rotor Complete
U-groove rotor complete for flexible medium-to-coarse spinning (Ne 10–30) on the Rieter R36 and R37 semi-automatic platform. Diamond top layer on the prepared substrate. 73-1-69 bearing rated to 80,000 rpm with a recommended ceiling of ≤ 72,000 rpm — dimensionally identical to the original, at 40–60% below OEM price.
S346/U-D — Complete Specifications
All measurements in millimetres. Every rotor complete assembly is 100% dynamically balanced on our own balancing line before shipment.
Why U Groove for General-Purpose Spinning
Where a mill runs mixed orders the U groove earns its place: a broad operating window through the medium-to-coarse range, tolerant of both fibre changes and count changes. Machine side and count side are confirmed as one selection, which is what keeps the rotor matched to the job.
U Groove — Applicable Yarn Count Range
Covers a wide band around Ne 10–30. Above Ne 30 the narrow T family takes over. Mills usually run a sample first to verify the groove on the machine before a bulk order.
U Groove — The Mixed-Order Profile
Mills running several orders on the same machines need a rotor that does not have to be changed when the count moves. The U profile’s wider zone is exactly that: stable at medium counts, still comfortable when the schedule goes coarser. Mills that run several counts per machine usually standardise on this profile.
One Rotor, Several Orders
Mixed-order mills can keep the same rotor in place as the schedule moves inside the band.
Straightforward Economics
A flexible rotor that reduces both change-out labour and the number of lines carried as spares.
Wide Count Window (Ne 10–30)
A broad operating band means fewer rotor changes when the count schedule shifts, cutting machine downtime.
Stable Fibre Collection
The wider deposition zone holds collection steady across mixed fibre lots, keeping yarn strength consistent between deliveries.
What D Means: Base and Working Surface
The trailing letters of the model code are two independent codes, not one word: B is the substrate, D is the working surface. The diamond face is the reason this rotor holds its groove profile on long runs. Confirm your fibre mix and speed with us before a bulk order. Standard lead time on coated rotors is 7–15 days, with urgent orders on request.
B = boronized (boron-steel) substrate. A diamond film is only microns thick, so the steel underneath decides whether it survives: a soft substrate deforms under fibre and grit impact and the film cracks and spalls off. The boronized base is the hardening step that keeps the diamond layer intact. This code does not carry the B step; it is the -BD- variant that pairs the diamond layer with the boronized base.
D = diamond top layer, grown on the prepared substrate as a micron-scale film. It takes the fibre and grit contact directly, which is where the wear resistance, the friction coefficient of 0.05–0.1 and the anti-stick behaviour come from that hold the groove profile over long runs. Diamond coating technology of US origin, applied on JSM’s own treatment line.
Which Rieter Machines Use S346/U-D?
On semi-automatic machines the bearing decides compatibility: 73-1-69 here, on the Rieter R36 and R37 platform.
What to Spin with S346/U-D
Application guidance for S346/U-D on the semi-automatic side of the Rieter range; speeds and counts follow the U groove specification.
✓ Mills wanting a simple, low-inventory spare-parts line
✓ General-purpose profile, medium to coarse yarns
✓ Medium–coarse counts, Ne 10–30
◇ Blends and speciality fibres — S groove
◇ Coarse counts Ne 3–16 — GL groove, large-diameter rotors
◇ Abrasive or recycled fibre — DN diamond coating
→ G: Standard (Ne 16–40)
→ T: Narrow (Ne 16–40)
→ TT: Extra narrow (Ne 16–40)
→ S: Special (Ne 16–40)
→ U: General purpose (Ne 10–30) — this model
→ See all 2 Rieter R36 and R37 rotor models →
S346/U-D — Frequently Asked Questions
Answers to the questions buyers ask most often about this rotor. If yours is not listed, send it with your machine model and current rotor code — we reply within 24 hours.
Is S346/U-D compatible with my Rieter R36 and R37 machine?
What does the model code S346/U-D mean?
What yarn counts does the U groove suit?
What do the letters BD mean in the model code S346/U-D?
How much does an OEM-equivalent rotor save versus the original?
Can I order the rotor spindle or rotor cup separately?
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Pre-filled: S346/U-D · Rieter R36 / R37 · diamond coating
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