S344/S-D Rotor Complete
Special-profile rotor complete for blends and speciality fibres (Ne 16–40) on the Rieter R36 and R37 semi-automatic platform. D — diamond coating over the rotor 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.
S344/S-D — Complete Specifications
All measurements in millimetres. Every rotor complete assembly is 100% dynamically balanced on our own balancing line before shipment.
Why S Groove for Blends and Speciality Fibres
S stands for special application: this profile exists for blends, man-made fibres and fibre mixes that a cotton groove would guide poorly. Because the count band is not published, the selection is checked against your fibre and target count before quoting.
S Groove — Applicable Yarn Count Range
Blend work is the design point here; for coarse counts move to the GL groove. Groove and cup size are confirmed together when the order is placed.
S Groove — Special Fibres, Predictable Yarn
The S groove is the profile mills reach for when the raw material is not straight cotton: viscose and modal blends, polyester-cotton mixes and other speciality fibre. Its geometry keeps the mixed ribbon guided instead of letting the longer component run ahead. The profile is best specified together with the actual blend ratio, not from the count alone.
Fewer Blend-Related Faults
Guides the mixed ribbon so the longer component does not run ahead and create faults.
Uniform Yarn Face
Even distribution of dissimilar fibres gives a more uniform yarn surface.
Tolerant of Lot Variation
Designed to absorb the variation that comes with buying speciality fibre lot by lot.
Right Tool for Speciality Work
Rather than forcing a cotton groove, the S profile is matched to the fibre mix.
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. Diamond top layer (HV 1000-1200) with a friction coefficient of 0.05–0.1, which reduces fibre damage at the groove face. Every assembly is 100% dynamically balanced before it leaves the balancing line.
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 S344/S-D?
This rotor runs the 73-1-69 bearing, shared by the Rieter R36 and R37 semi-automatic machines. Models in the group differ by groove and rotor size, not by bearing fit.
What to Spin with S344/S-D
How this rotor is applied on Rieter R36 and R37 machines, with the S groove’s count window where one is published.
✓ Mills buying speciality fibre lot by lot
✓ Yarns where blend consistency is judged downstream
✓ Applications a straight cotton groove handles poorly
◇ Medium–coarse counts Ne 10–30 — U groove
◇ Coarse counts Ne 3–16 — GL groove
◇ Abrasive blends — DN diamond coating
→ GL: Large (Ne 3–16)
→ G: Standard (Ne 16–40)
→ T: Narrow (Ne 16–40)
→ TT: Extra narrow (Ne 16–40)
→ S: Special (Ne 16–40) — this model
→ See all 2 Rieter R36 and R37 rotor models →
S344/S-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 S344/S-D compatible with my Rieter R36 and R37 machine?
What does the model code S344/S-D mean?
What yarn counts does the S groove suit?
What do the letters BD mean in the model code S344/S-D?
How much does an OEM-equivalent rotor save versus the original?
Can I order the rotor spindle or rotor cup separately?
Order S344/S-D Rotors
Pre-filled: S344/S-D · Rieter R36 / R37 · diamond coating
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