Bale Wrapper Application Case
Electrical and Pneumatic/Hydraulic Hybrid Slip Ring for Bale Wrapper
A through-bore hybrid slip ring transfers power, control signals and one pneumatic or fluid line between the fixed frame and rotating wrapping mechanism. The assembly fits around the centre shaft and removes the cable and hose winding problem created by continuous rotation.
Power Voltage
Rated Speed
Electrical
High Current
Bale Wrapper Project Background
Bale wrappers rotate a turntable, wrapping arm or wrapping head while film is applied around hay or silage bales. The controller remains on the fixed frame, while sensors, switches and actuators may be located on the rotating section.
Published bale-wrapper designs place a slip ring at the centre shaft or rotation gearbox so electrical connections can pass from the stationary machine to the rotating assembly. Modern wrappers also use hydraulic cut-and-hold or clamping functions, so electrical and fluid services often have to be designed around the same rotary area.
For this layout, a through-bore electrical + pneumatic/hydraulic hybrid slip ring combines the electrical circuits and one media channel in a single compact assembly.
For ByTune's mainstream BTH platforms, model differences mainly define the mechanical envelope and through-bore size. Circuit count, current, signal type, lead length and protection are configured to the actual machine.
Bale Wrapper Rotary Transmission Requirements
Electrical transmission
The rotating side needs a small number of power circuits together with low-current control or sensor circuits.
- Power voltage up to 600V
- 5A / 10A / 15A / 20A standard circuit options on mainstream platforms
- Higher-current configurations up to 50A when cable space and design allow
- 12/24V control and sensor circuits can coexist with higher-voltage power
- Electrical noise ≤7 mΩ for stable sensitive-signal transmission
Pneumatic / hydraulic transmission
One air or fluid line crosses the same rotary interface when the rotating section uses a clamp, cutter or actuator.
- Single-channel or multi-channel media configuration available.
- Pneumatic pressure matched to the actual air system.
- Hydraulic configuration up to 350 bar.
- Port size selected based on flow rate, piping, and installation space.
- Media-specific seals; pneumatic and hydraulic designs are not interchangeable.
Mechanical installation
The centre shaft or gearbox already occupies the rotation axis, so the slip ring must fit around the existing structure.
- Ø38 mm reference through bore
- Compact axial envelope
- Fixed stator / rotating rotor
- Anti-rotation bracket or flange
- Custom cable and port direction
Agricultural environment
Hay dust, dirt, moisture and vibration require better sealing than an indoor open-frame rotary connection.
- IP65 sealed housing
- Protected cable outlets
- Aluminum or corrosion-resistant housing
- -20°C to +60°C reference range
- Vibration-resistant mounting
Rotary Connection Problems in Bale Wrapper Machines
Cable winding at the rotation axis
Fixed electrical wiring winds around the shaft when the wrapper rotates repeatedly in the same direction. The result is conductor fatigue, insulation stress and an unreliable connection.
01
Pneumatic or fluid hose twisting
A hose routed directly across the rotary joint bends and winds with the wrapping mechanism, adding stress to the hose and fittings.
02
Limited installation space
The shaft, gearbox and mounting frame already occupy the centre of the machine, leaving little room for a separate slip ring and separate rotary union.
03
Dust and moisture at the contacts
Hay, crop residue and outdoor moisture can enter an unsealed housing and increase the risk of unstable electrical contact or corrosion.
04
Integrated hybrid or modular electrical + pneumatic/hydraulic design
The application does not have to be locked to one mechanical architecture. ByTune can select the arrangement according to space, serviceability, media pressure and the number of electrical/media channels.
Integrated Hybrid Assembly
Electrical circuits and media passages are combined in one rotary unit around the same axis.
- Compact single-body installation
- Power + signal + pneumatic/hydraulic in one assembly
- Useful where axial space and mounting points favor integration
- Media section designed for the actual medium and pressure
Modular Paired Solution
A through-bore electrical slip ring is paired with a separate pneumatic or hydraulic rotary union.
- Electrical and media modules can be selected independently
- Easier to change circuit count without changing the pneumatic module
- Practical for standard BTH platforms paired with BTA media units
- Useful when service or mounting layout favors separate components
BTH2586 + BTA056-0401 for 360° electrical + 4-channel pneumatic transmission
The BTH2586 through-hole electric slip ring is used in conjunction with the BTA056-0401 four-channel pneumatic rotary joint. This combination is used in agricultural equipment and industrial packaging machinery to transmit power, control signals, and multiple compressed air or vacuum lines through a continuously rotating interface, thereby preventing cables and pneumatic hoses from twisting or tangling during 360° rotation.
Power + Control Signals + 4 Pneumatic / Vacuum Channels Through 360° Rotation
The two rotary modules work together at the same rotating interface. The BTH2586 carries electrical power, control and sensor signals around the centre shaft, while the BTA056-0401 maintains four independent compressed-air or vacuum channels. Both services remain connected during continuous 360° rotation without forcing electrical cables or pneumatic tubing to wind around the machine axis.
BTH2586 - Electrical Module
25.4 mm through bore. Handles electrical power together with control and sensor signals during continuous rotation. Circuit count, current, voltage and signal type can be configured according to the machine while the BTH2586 housing provides the standard 25.4 mm mechanical platform.
BTA056-0401 - Pneumatic Module
Four independent pneumatic channels for compressed air or vacuum. The rotary union keeps multiple air/vacuum lines connected through continuous 360° motion so the tubing does not twist around the rotating mechanism. Port size, pressure and sealing are selected for the actual pneumatic system.
25.4mm
BTH2586 Through Bore
Power +Control
Electrical + Signal Transmission
4Channels
Compressed Air / Vacuum
360°
Continuous Rotary Transmission
Main problem solved: power, control signals and four compressed-air / vacuum lines can cross the same continuously rotating interface without electrical cables or pneumatic hoses winding around the axis. For agricultural equipment, the configuration can emphasize dust, mud, water exposure, vibration and protected cable routing; for industrial packaging machinery, it can emphasize low electrical noise, stable control signals and continuous-duty operation.
Three mainstream through-bore platforms for this type of application
BTH2586
25.4 mm bore · 86 mm OD
Up to 72 standard rings
5A / 10A / 15A / 20A standard circuits
380VAC/DC; 600V optional
1000 rpm rated speed
BTH3899
38 mm bore · 99 mm OD
Up to 72 standard rings
5A / 10A / 15A / 20A standard circuits
380VAC/DC; 600V optional
1000 rpm rated speed
BTH50120
50 mm bore · 120 mm OD
Up to 72 standard rings
5A / 10A / 15A / 20A standard circuits
380VAC/DC; 600V optional
1000 rpm rated speed
Smaller through-bore models have tighter wire and contact space, so their practical current is usually lower. Higher-current and special-signal designs should be evaluated against bore size, outer diameter, circuit count and cable gauge rather than treated as a fixed value for every BTH model.
ByTune Hybrid Slip Ring Solution
The bale-wrapper rotary interface is built from a suitable through-bore electrical platform and, where required, a pneumatic or hydraulic media section. The solution can be an integrated hybrid assembly or a modular BTH + BTA combination, depending on shaft size, media channels, pressure, serviceability and available installation space.
| Machine Requirement | ByTune Solution | What It Solves |
|---|---|---|
| Power and control on the rotating side | Power up to 600V, low-voltage control/sensor circuits, and mixed power + signal configurations. Mainstream BTH platforms support 5A / 10A / 15A / 20A standard circuits, with up to 50A custom options where space and cable gauge allow. Low-noise configurations can achieve electrical noise ≤7 mΩ. | Keeps high-voltage power, control and sensitive sensor signals connected through continuous 360° rotation without winding the cable harness. |
| Pneumatic or hydraulic services | Integrated single/multiple media passages or a separate rotary union. A similar paired application uses BTA056-0401 with 4 compressed-air / vacuum channels; hydraulic versions can be configured up to 350 bar according to medium, seals and operating conditions. | Transfers air, vacuum or hydraulic media across the rotating interface instead of routing hoses around the shaft. |
| Centre shaft already in use | Choose the through-bore platform by shaft diameter: BTH2586 - 25.4 mm, BTH3899 - 38 mm, or BTH50120 - 50 mm. Other bore sizes are available. | Keeps the existing shaft inside the hollow centre while the electrical and media connections rotate around the same axis. |
| Outdoor agricultural environment | IP65 reference configurations with higher sealing options, including IP68 where required, plus protected cable exits and corrosion-resistant housing options. | Helps protect the contact system from hay dust, soil, mud, rain, washing water and moisture. |
| Compact installation area | Integrated hybrid design when one body is preferred, or modular BTH + BTA arrangement when electrical and pneumatic sections need to be selected or serviced independently. | Reduces cable/hose routing around the rotating centre while giving the machine designer flexibility in mounting and service layout. |
Application Benefits
Why this platform approach works for agricultural wrapping equipment
High-voltage power without understating capability
600V-capable platforms avoid presenting the slip ring as a low-voltage-only component while still allowing dedicated 12/24V control circuits.
Stable sensitive-signal transmission
Low electrical noise and separate circuit planning support sensors and control signals alongside power circuits.
Scalable mechanical platform
25.4, 38 and 50 mm common bores cover a wide range of shafts without treating each machine as a completely new product family.
Built for field conditions
IP protection, sealed cable exits and application-specific housing options address dust, water, mud and vibration in agricultural service.
Bale Wrapper Slip Ring Installation
The hybrid slip ring is installed at the centre of rotation between the fixed frame and rotating wrapping assembly.
Up to 600V power
12/24V control / sensor
Air or hydraulic supply
25.4 / 38 / 50 mm through bore
Power + sensitive signals
Integrated or paired media channels
Motors / heaters
Sensors / switches / valves
Clamp / cutter / actuator functions
The slip ring transfers electrical energy and signals; it should not be used as the structural bearing or drive-torque member for the wrapping mechanism.
Results of the Hybrid Slip Ring Solution
Continuous electrical connection
Power and signal circuits remain connected through repeated wrapping cycles without winding the stationary cable harness.
Integrated media transfer
The pneumatic or fluid line passes through the rotary assembly instead of using an external hose loop around the shaft.
Simpler centre-shaft assembly
The through-bore structure keeps the centre shaft available and combines two rotary functions in one installation position.
Better field protection
IP65 sealing keeps hay dust, dirt and outdoor moisture away from the electrical contact system.
Custom Bale Wrapper Slip Ring Options
The hybrid architecture can be adapted to the wrapper shaft, electrical load, media system and field environment.
Shaft & envelope
Centre-shaft diameter, maximum OD, axial length, mounting interface and anti-rotation method.
Power circuits
Number of circuits, voltage and current per circuit. Tell us where 600V or higher-current channels are required.
Sensitive signals
12/24V control, encoder, sensor, CAN, RS485, Ethernet or other signal types that require low-noise transmission.
Media channels
Air or hydraulic oil, number of ports, pressure, flow, port thread and tubing size.
Field environment
Dust, mud, rain, washdown, temperature, vibration and target IP rating.
Connections
Lead length, cable gauge, protective conduit, connector, cable outlet and media port direction.
Bale Wrapper Hybrid Slip Ring Inquiry
Send the centre-shaft diameter, circuit list, current, machine voltage, rotation speed, working medium and pressure. We will match the through bore, electrical channels, media passage, sealing and mounting interface to the wrapper.