Slip shafts, slip rings and friction elements for slitting, rewinding and multi-roll winding applications.
KENDORIC supplies multiple slip shaft structures for slitting and rewinding lines where finished rolls require controlled torque, stable core contact and balanced winding quality.
How Slip Shafts Work
Slip shafts allow each finished roll to slip independently during rewinding. This helps compensate for small differences in finished roll diameter after slitting and keeps each roll under more consistent winding torque.
Use the core-contact structure as a starting point, then confirm it with a photograph of the old ring and shaft. The outside diameter alone does not distinguish rings intended for the same core size. On pneumatic designs, the air path and internal dimensions complete the identification.
If the core contact uses steel balls, check whether the installed ring is single-ball or double-ball. The ball family also distinguishes centre-air, pneumatic side-pressure and mechanical side-pressure operation.
Identify ball slip ringsThe double-ball and roller design uses extended cylindrical contact points. Compare that contact structure and the standard 60 mm bore or 55 mm bearing version, rather than identifying the ring from its outer diameter alone.
Compare roller contact ringsRectangular metal keys or rubber keys identify the key-type contact arrangement. The friction material is a separate selection: kraft and wool felt give different pull-force curves.
See key and friction-material choicesFor an air shaft with piston or expansion-piece rings, count the pistons and confirm a single air path or dual-air-path XC arrangement. The existing ranges distinguish 8, 12 and 16 pistons by application.
Match air-operated ringsDS uses pneumatic locking and slip, with a published starting pressure of at least 0.8 kg/cm². Match the 45 mm bore on its 3-inch version or the 70 mm bore on its 6-inch build.
Identify DS dimensionsThe low-tension structure combines roller positioning balls and bearings and works from 0.1 kg/cm². Confirm that structure and its 50 mm standard bore if the machine handles thin PET, electronic film or separator film.
Check the low-tension arrangement| Structure | Minimum slit width | Starting air pressure | Suitable cores | Typical web materials |
|---|---|---|---|---|
| Air / piston rings | — | — | 3-inch; paper, plastic or composite cores | Packaging film; lithium electrode and separator (12 pistons); battery copper/aluminium foil (16 pistons) |
| Ball rings | From 5 mm, subject to shaft/ring layout | — | 3-inch or 6-inch paper cores | Film, paper and label stock |
| Double ball and roller | — | — | 3-inch or 6-inch; rubber, aluminium or paper cores | — |
| DS | — | ≥0.8 kg/cm² | 3-inch or 6-inch; paper or plastic cores | Flexible packaging laminates; medium-tension film |
| Key type | — | — | 3-inch or 6-inch; rubber or aluminium cores | — |
| Low tension | — | From 0.1 kg/cm² | 3-inch; rubber, aluminium or paper cores | 10 µm PET, electronic film and lithium separator |
“—” means a minimum or material-specific value is not published on the corresponding model page. Ring width and minimum slit width are different measurements: the ball structure’s 5 mm figure depends on the shaft and ring layout, while the replacement itself must match the actual ring dimensions.
A 3-inch core is nominally 76.2 mm inside diameter and a 6-inch core 152.4 mm. Core material, ring bore, width and connection details still need checking even where two structures take the same nominal core size.
Slip rings can be supplied separately, including rings for shafts from other manufacturers when the dimensions match. Send an old-ring photograph and the shaft drawing so we can check the structure, ring bore and width, core inside diameter, keyway or air-hole positions, and quantity before quoting. Availability and lead time are confirmed with the quotation.
Select the closest structure for its measurement checklist:
If you are comparing quotations from several countries, these all describe the same product. We list them because the wording on a drawing or an enquiry rarely matches ours.
| Term | Where you will see it |
|---|---|
| Differential rewind shaft | The most common term in European and American converting; usually refers to the complete shaft |
| Friction shaft / differential friction shaft | Used interchangeably with differential rewind shaft, emphasising how the torque is transmitted |
| Friction ring / differential friction ring | The individual rings that slip on the shaft body — what we call the slip ring below |
| Slip shaft / slip ring | Direct translation of the Chinese and Japanese term; common in Asian catalogues, including ours |
Select the shaft and ring structure according to core size, finished roll width, material sensitivity, roll weight and required winding tension range.
Air slip shafts combine pneumatic core locking with controlled differential slip for accurate torque and stable multi-roll winding.
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Low tension slip shafts are designed for sensitive materials that require stable winding at low air pressure and low torque.
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DS slip shafts provide pneumatic locking and controlled slip for medium-tension film slitting and rewinding applications.
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Ball slip shafts can be configured as center-air, pneumatic side-pressure or mechanical side-pressure structures for flexible narrow-roll winding.
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Double ball and roller slip shafts use extended expansion contact points to support stable core holding and winding torque.
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Key slip shafts use rectangular metal or rubber keys to expand and contact the core for controlled differential winding.
View DetailsApplication Fit
Slip shafts help compensate for small roll diameter differences after slitting, so each finished roll can wind with a more controlled and consistent torque.
| Typical Machines | Slitting machines, rewinding machines and finishing lines |
|---|---|
| Core Sizes | 3-inch and 6-inch core IDs, with custom options depending on shaft and ring structure |
| Selection Inputs | Core ID, finished roll width, roll diameter, roll weight, material, line speed and target winding tension range |
| Available Structures | Air, low-tension, DS, ball, double-ball roller and key-type slip shaft structures |
Send the core ID, finished roll width, roll diameter, roll weight, material and winding tension range. KENDORIC will help match the shaft and ring structure.
Pressures are given in kg/cm² as published by the manufacturer. For conversion: 1 kg/cm² = 0.98 bar = 14.2 psi. So 1 kg/cm² ≈ 1 bar, and 5 kg/cm² ≈ 4.9 bar ≈ 71 psi.
How to use these figures: they are reference values for a single ring, measured under the stated test conditions — that ring width, that friction material and that groove. Total winding torque on your machine depends on how many rings are on the shaft, the roll diameter as it builds, the condition of the friction material and the line speed, so these numbers cannot be used directly to calculate web tension. Send us the slit widths, the number of rolls across and the tension range you need, and we will confirm the ring configuration before you size anything.
Keep the test configuration attached to each set of values. A measured ring bore, width or friction material can differ from the standard replacement range. In particular, the air-shaft page identifies its displayed curves as key-type reference data; they are not measurements of every piston-ring variant.
Tell us the core size, the material and the slit widths, and we will come back with a shaft and ring configuration.
Have a drawing of your shaft or a photo of the old rings? Send it on WhatsApp or to sales@kendoric.com — we check fit before quoting.