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
Stable core contact for controlled differential winding.
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 a double ball and roller shaft is used
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
Slip ring options and core-contact details
Double-ball and roller slip rings can be selected according to core size, ring width, contact structure, core material and required winding torque.
- 3-inch ring outside diameter is 75.5 mm and expands to 78.2 mm.
- 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
Confirm core material, core inner diameter, required width, winding tension range, shaft structure and whether the application needs low starting tension or higher roll-holding force.
Technical Reference Data
Pull force and air pressure reference values for preliminary selection.
Reference values should be confirmed according to the actual shaft structure, ring width, groove material, core material and air path before final selection.
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.
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 |
Related Slip Shaft Types
Air Slip Shaft
Air slip shafts combine pneumatic core locking with controlled differential slip for accurate torque and stable multi-roll winding.
View DetailsLow Tension Slip Shaft
Low tension slip shafts are designed for sensitive materials that require stable winding at low air pressure and low torque.
View DetailsDS Slip Shaft
DS slip shafts provide pneumatic core locking and controlled slip for medium-tension film slitting and rewinding applications.
View DetailsBall Slip Shaft
Ball slip shafts can be configured as center-air, pneumatic side-pressure or mechanical side-pressure structures for flexible narrow-roll winding.
View DetailsKey Slip Shaft
Key slip shafts use rectangular metal or rubber keys to expand and contact the core for controlled differential winding.
View Details