Heavier or wider rolls
The expansion point is a long cylinder rather than a point, spreading the load along the core.
High-Contact Differential Winding Shaft
Double Ball and Roller Differential Friction Shaft
Double ball and roller slip shafts use extended expansion contact points to support stable core holding, repeatable pull force and controlled winding torque. Also known as: double ball and roller slip shaft, roller friction shaft.
Double-Ball Roller Winding Structure
Extended cylindrical contact for core holding
Suitable for 3-inch and 6-inch core winding with rubber, aluminum or paper cores where stronger ring contact and repeatable pull force are required.
- Uses roller-type slip rings with extended cylindrical contact points.
- Can be matched with center-air or side-pressure key-type slip ring structures depending on the shaft design.
- Designed for stable core contact and controlled differential winding.
| 3-inch Ring | 75.5 mm OD, 78.2 mm expansion point |
|---|---|
| 6-inch Ring | 151 mm OD, 155.5 mm expansion point |
| Core Materials | Rubber, aluminum and paper cores |
| Widths | 3-inch: 15-50 mm; 6-inch: 25-50 mm |
| Inner Diameters | 60 mm standard, 55 mm with bearing, custom to shaft core |
Where roller contact changes the winding comparison
Where core marking matters
Extended contact reduces the local pressure on the core, which matters on thin-wall or plastic cores.
Repeatable pull force
The published test series shows ring-to-ring consistency at a fixed pressure, which is what matters when one shaft carries a dozen rolls.
Rubber, aluminum and paper cores
Both 3-inch and 6-inch ring sizes cover the common core materials.
Slip Ring
Roller-ring core materials, bearing options and widths
Double-ball and roller slip rings can be selected according to core size, ring width, contact structure, core material and required winding torque.
- The 3-inch roller ring measures 75.5 mm outside diameter, reaching 78.2 mm when expanded.
- Suitable 3-inch core inner diameter is 76.2 +/- 0.2 mm for rubber, aluminum or paper cores.
- 3-inch standard widths include 15, 20, 25, 30, 35, 40 and 50 mm; other widths can be designed to order.
- Standard inner diameters include 60 mm and 55 mm with bearing; other sizes can be made to match the shaft core.
- 6-inch ring outside diameter is 151 mm and expands to 155.5 mm.
- Suitable 6-inch core inner diameter is 152.4 +/- 0.2 mm for rubber, aluminum or paper cores.
- 6-inch standard widths include 25, 30, 35, 45 and 50 mm; other sizes can be customized.
Selection Notes
Record whether the core is rubber, aluminum or paper before comparing roller rings. The extended cylindrical contact is the distinguishing feature of this page, so identify that structure alongside the bore and bearing arrangement. Compare the actual ring width with the applicable 3-inch or 6-inch range, rather than using core diameter as the sole replacement criterion.
Replacement Slip Rings
Replacement roller rings matched to contact and bearing layout
Availability
Double-ball and roller rings can be ordered on their own rather than as a complete shaft. Matching dimensions allow a ring for a shaft from another manufacturer to be reviewed, including its bearing and contact arrangement. Lead time for that agreed configuration is confirmed with the quotation.
What to measure / send
Confirm the roller contact structure and whether the ring bore is the standard 60 mm or the 55 mm bearing version. Identify the core material as rubber, aluminum or paper, then measure core inner diameter and ring width. The core reference is 76.2 mm for 3-inch or 152.4 mm for 6-inch. Mark the shaft keyslot or air-hole positions and send the required quantity with photographs of the old roller ring and the shaft it runs on.
What ships
The quoted item is a same-structure double-ball and roller slip ring, configured for the approved bore, ring width and friction material. A 55 mm bearing arrangement and a 60 mm standard bore are different requests; the supplied configuration follows the dimensional review and the identified core material.
Keep the contact shape in the replacement specification
The roller version uses an extended cylindrical contact point instead of the more localized contact described for ball structures. That distinction is why this page discusses stable core contact and repeatable winding pull force. A measurement request should retain the contact structure, not reduce the assembly to an outside diameter. Include the core material and the old ring photograph so the review can distinguish a roller-contact replacement from a ball ring or rectangular-key ring that happens to suit a similar nominal core.
Separate bearing fit from the published force comparison
The standard inner-diameter options here are 60 mm and 55 mm with bearing, with other sizes matched to the shaft core. Width options also differ between the three-inch and six-inch versions. The two force series below compare a 25 mm double-ball plus roller ring with kraft material and a 25 mm double-ball ring with wool felt. Their pressures and materials are stated separately. Preserve that distinction when describing your present ring: neither series establishes the configuration of every replacement that fits a rubber, aluminum or paper core.
Technical Reference Data
Kraft roller and wool-felt ball tests under their stated conditions
Double-ball and roller force data below retain the individual test dimensions, materials and pressure conditions; compare those conditions with the ring you need.
Use the category explanation to read the roller and double-ball force series in context.
25 mm Double-Ball + Roller Slip Ring Pull Force
Test condition: 19 grooves with kraft material, 25 mm wide double-ball plus roller slip ring.
| Item | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Air Pressure (kg/cm2) | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 |
| Pull Force (N) | 68.7 | 65.4 | 65.8 | 66.8 | 65.8 | 66.7 | 65.8 | 65.7 | 67.5 | 66.4 | 65.6 | 60.3 |
| Air Pressure (kg/cm2) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Pull Force (N) | 62.7 | 60.8 | 61.8 | 66.8 | 61.9 | 63.7 | 67.8 | 63.7 | 62.4 | 63.8 | 60.2 | 64.5 |
25 mm Double-Ball Slip Ring Pull Force
Test condition: 19 grooves with wool felt, 25 mm wide double-ball slip ring.
| Item | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Air Pressure (kg/cm2) | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
| Pull Force (N) | 30.0 | 36.4 | 35.8 | 31.4 | 38.4 | 40.3 | 32.8 | 34.3 | 37.1 | 34.8 | 32.4 | 35.3 |
| Air Pressure (kg/cm2) | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
| Pull Force (N) | 33.7 | 38.1 | 34.5 | 32.7 | 33.2 | 36.5 | 36.3 | 34.5 | 35.6 | 33.9 | 35.8 | 33.2 |
Compare roller contact with ball points and rectangular keys
Air Slip Shaft
If pneumatic piston selection is more relevant than extended roller contact, the air family separates packaging-film, electrode/separator and battery-foil duties by piston count.
View DetailsLow Tension Slip Shaft
When sensitive film needs a stated low starting pressure, compare the dedicated 0.1 kg/cm² design rather than using the roller force samples as a starting-pressure claim.
View DetailsDS Slip Shaft
A medium-tension laminate duty may call for a DS comparison, with core size, its different bore dimensions and the 0.8 kg/cm² starting boundary checked together.
View DetailsBall Slip Shaft
For slitting widths approaching 5 mm, look at the ball family’s narrow-roll layout instead of deriving a minimum slit width from this roller page.
View DetailsKey Slip Shaft
Rectangular metal and rubber keys offer a different core-contact choice from cylindrical rollers; compare that page when key material is the required specification.
View DetailsSend roller-ring dimensions and core material for review
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.