Positive core engagement
Rectangular metal or rubber keys bite into the core rather than relying on friction alone, for cores that tend to slip.
Key-Type Core Contact Slip Shaft
Key Differential Friction Shaft
Key slip shafts use rectangular metal or rubber keys to expand and contact the core, providing controlled core engagement and differential winding torque for slitting and rewinding applications. Also known as: key slip shaft, key-type friction shaft.
Key-Type Winding Structure
Controlled core engagement for differential winding.
Suitable for 3-inch and 6-inch winding cores, especially rubber and aluminum cores that require key-type core contact.
- Configured with key-type slip rings using rectangular metal keys or rectangular rubber keys.
- Available for center-air and side-pressure key-type slip ring structures.
- The key contact structure provides controlled core engagement for differential winding.
| Key Types | Rectangular metal key or rectangular rubber key |
|---|---|
| 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 and aluminum cores |
| Widths | 3-inch: 10–50 mm; 6-inch: 25–50 mm |
Where a key differential friction shaft is used
Two friction materials
Kraft and wool felt give noticeably different pull force curves at the same pressure — kraft roughly double the felt figure in the published data. Specify which you want.
Rubber and aluminum cores
Both 3-inch and 6-inch, with widths from 10 mm to 50 mm.
Rubber keys for softer cores
Where a metal key would mark the core, the rubber key version is the alternative.
Slip Ring
Slip ring options and core-contact details
Key-type slip rings can be selected according to core size, key material, ring width, pressure method and required winding torque.
- 3-inch and side-pressure ring outside diameter is 75.5 mm, expanding to 78.2 mm.
- Suitable 3-inch core inner diameter is 76.2 ± 0.2 mm for rubber or aluminum cores.
- Standard widths include 10, 15, 20, 25, 30, 35, 40 and 50 mm; other widths can be designed to order.
- Inner diameter options include 50 mm and 55 mm with bearing; other dimensions 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 or aluminum 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, key material, groove 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.
Key Slip Shaft Pull Force, Kraft Material, Low Pressure Range
Test condition: 3-inch key-type slip ring, 30 mm width, 100 mm outside diameter, 60 mm inner diameter, 20 x 3 groove with kraft material.
| Air Pressure (kg/cm2) | 0 | 0.2 | 0.4 | 0.6 | 0.8 | 1.0 | 1.2 | 1.4 | 1.6 | 1.8 | 2.0 | 2.2 | 2.4 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pull Force (kg) | 0.16 | 0.19 | 0.38 | 0.57 | 0.78 | 1.00 | 1.32 | 1.48 | 1.88 | 2.27 | 2.64 | 2.88 | 3.12 |
Key Slip Shaft Pull Force, Kraft Material, High Pressure Range
Continuation of the 3-inch key-type slip ring kraft-material test.
| Air Pressure (kg/cm2) | 2.6 | 2.8 | 3.0 | 3.2 | 3.4 | 3.6 | 3.8 | 4.0 | 4.2 | 4.4 | 4.6 | 4.8 | 5.0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pull Force (kg) | 3.33 | 3.80 | 4.03 | 4.23 | 4.41 | 4.74 | 4.78 | 5.23 | 5.43 | 5.64 | 5.82 | 6.15 | 6.36 |
Key Slip Shaft Pull Force, Wool Felt, Low Pressure Range
Test condition: 3-inch double-ball slip ring, 25 mm width, 60 mm inner diameter, 20 x 3 groove with wool felt.
| Air Pressure (kg/cm2) | 0 | 0.2 | 0.4 | 0.6 | 0.8 | 1.0 | 1.2 | 1.4 | 1.6 | 1.8 | 2.0 | 2.2 | 2.4 | 2.6 | 2.8 | 3.0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pull Force (kg) | 0.02 | 0.04 | 0.11 | 0.23 | 0.42 | 0.64 | 0.80 | 1.03 | 1.23 | 1.47 | 1.64 | 1.86 | 2.02 | 2.28 | 2.43 | 2.65 |
Key Slip Shaft Pull Force, Wool Felt, High Pressure Range
Continuation of the wool-felt groove test.
| Air Pressure (kg/cm2) | 3.2 | 3.4 | 3.6 | 3.8 | 4.0 | 4.2 | 4.4 | 4.6 | 4.8 | 5.0 | 5.2 | 5.4 | 5.6 | 5.8 | 6.0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pull Force (kg) | 2.83 | 3.03 | 3.25 | 3.47 | 3.67 | 3.84 | 4.01 | 4.28 | 4.48 | 4.62 | 4.83 | 5.03 | 5.26 | 5.46 | 5.67 |
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 DetailsDouble Ball and Roller Slip Shaft
Double ball and roller slip shafts use extended expansion contact points to support stable core holding and winding torque.
View Details