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Large-diameter slip rings

Stemmann-Technik LP series bako large-diameter slip ring

Modular contact-plate slip ring system from 46 to 950 mm, with free bores up to 950 mm, flat or concentric low-height designs, high-current and medium-voltage (up to 30 kV) options, encoder fixtures and media distributors.

Need this part, a replacement or a complete package? Our experienced UK engineering team helps you select, source and obtain the right products, with pricing, delivery coordination and after-sales support.

Pricing and availability

Get pricing, sourcing and replacement support

Need Stemmann-Technik parts, a replacement or a suitable alternative? Send us a part number, or tell us what the machine needs to do. Our UK engineers will come back with the right product, pricing, lead time and delivery, whether that is the original part, a checked alternative or a complete axis.

  • Original parts or a checked alternative
  • Pricing, lead time and delivery in one reply
  • Components, complete axes and ongoing support

No obligation. Add what you know and an engineer will help with the rest. Prefer to configure it? Build a specification.

Add quantity, timing or application notes (optional)

Spec builder

Specify what you need instead of LP series bako

Select every part you need and answer the questions an applications engineer would ask. Our engineers use your specification to come back with the right products, pricing and lead times. You see your summary before we ask for any details.

Already know the part number? Send it to us directly.

  1. 1Products
  2. 2Performance
  3. 3Environment
  4. 4Volumes
  5. 5Your spec
Step 1 of 5

What are you specifying?

Select everything you need. A motor, drive and gearbox can be specified together as one axis.

1 selected: Slip ring

Key specifications

Voltage (max)30,000 V
Bore (max)950 mm
Outer diameter46–950 mm
Ingress protectionIP54 to IP65 (LP60)
Voltage notemedium-voltage components up to 30 kV offered as an option
Od notesizes 46–950 mm as published

Summarised in our own words from Wabtec Corporation's published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1

Notes on this data

Current per ring, speed and temperature not published.

Specify Motion is not affiliated with Wabtec Corporation. Stemmann-Technik and LP series bako are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.

Engineer support

Speak to our engineers about your project

Our experienced engineers are on hand, ready to help with your project. Whether you need the Stemmann-Technik LP series bako itself, help sourcing it, or a modified or custom design built around your load, speed and space, tell us what the machine has to do and we'll come back with the right option.

  • Help sourcing LP series bako and spares for installed machines
  • Modified and custom designs when a catalogue part doesn't fit
  • Complete axis: motor, drive, gearing and feedback matched together

Typical applications

CranesWind energy systemsRadar installations

What a large-diameter slip ring is

A large-diameter slip ring is a rotary joint with a bore or ring diameter typically of several hundred millimetres up to a few metres, built for very large rotating structures. The rings are often fabricated in segments or machined as drums or platters, with brush blocks mounted around the stationary frame. Because the structure is large, they are usually designed to match the customer's machine and may integrate power, signal, data, fibre or contactless channels and media passages in one assembly.

When engineers choose a large-diameter slip ring

Choose a large-diameter design when the rotating structure has a big central opening, such as CT gantries, large turntables, radar pedestals, cranes and slewing platforms, or when cabling and services must pass through a wide bore. The trade-offs are cost, lead time and high surface speed even at modest rpm, which limits speed and raises brush wear. Mechanical runout of the machine becomes significant at this scale, so the slip ring is usually designed alongside the structure rather than chosen from a catalogue.

How to specify the Stemmann-Technik LP series bako

Send these with your enquiry and an engineer can confirm the right LP series bako variant or an equivalent:

  • Bore and outer diameter limits (mm)
  • Speed and surface speed (rpm, m/s)
  • Power circuits, current and voltage (A, V)
  • Data rates and channels, including contactless or fibre
  • Structure runout and flatness at the mounting faces (mm)
  • Environment: outdoor exposure, IP code and temperature (°C)
  • Segmentation for installation and maintenance access

Common mistakes to avoid

  • Specifying late, when the structure leaves too little room or too much runout for the slip ring
  • Using the catalogue rpm without checking surface speed at the actual diameter
  • Not planning how the ring will be lifted, installed and serviced in place
  • Leaving out data rate growth, so the channel count is outgrown within the machine's life

Stemmann-Technik LP series bako: frequently asked questions

Can you help replace Stemmann-Technik LP series bako or source the original?

Send the full model code, quantity and required date. Our engineers can check original-part availability and assess suitable alternatives, including supply-network options where appropriate. We confirm compatibility and any changes needed before recommending a replacement.

What is the Stemmann-Technik LP series bako?

Modular contact-plate slip ring system from 46 to 950 mm, with free bores up to 950 mm, flat or concentric low-height designs, high-current and medium-voltage (up to 30 kV) options, encoder fixtures and media distributors. Published series figures include voltage 30,000 V, bore 950 mm, outer diameter 46 mm, outer diameter 950 mm. It is made by Wabtec Corporation; Specify Motion can help source it or propose an equivalent.

Who makes the Stemmann-Technik LP series bako?

The Stemmann-Technik LP series bako is made by Stemmann-Technik (Wabtec Corporation) and is listed here for engineers comparing options. Specify Motion is not affiliated with Wabtec Corporation; brand names are used only to identify the product.

What is the voltage of the Stemmann-Technik LP series bako?

The published series maximum voltage is 30,000 V. Individual models and sizes in the LP series bako range vary, so check the exact variant against your duty cycle, mounting and environment, or ask our engineers to confirm the right size for you.

Is there an alternative to the Stemmann-Technik LP series bako?

We can assess suitable replacement options. Our engineers can review the original model and propose options for your load, speed and environment. An engineer confirms the fit against your application before recommending anything.

Why do large slip rings have lower speed ratings?

Surface speed is diameter multiplied by rotational speed, so a ring a metre across turning at 60 rpm already runs faster at the contact than a small capsule at a thousand rpm. Brush wear, heat and contact bounce all rise with surface speed. Large-diameter designs manage this with brush materials, contact force and runout control, but their rpm ratings are typically far lower.

How is high-speed data passed through a large-diameter slip ring?

Contact rings work for slower networks, but for very high data rates, such as CT image data, large rings often use contactless capacitive, inductive or optical transmission around the circumference. A fibre optic rotary joint can also be placed on the axis if the centre is accessible. State the data rate and latency requirements early, as they shape the whole design.

Further reading: How to select a slip ring · How to select a fibre optic rotary joint · Slip rings

Other large-diameter slip rings series

Engineer support

Our engineers are ready to help with your project

Tell us about your project and how you use the Stemmann-Technik LP series bako: the load, speed, duty and environment. An experienced engineer will review it and reply, normally within one working day.

  • Reviewed by an engineer, not an autoresponder
  • Like-for-like and better-fit alternatives
  • Standard, modified and custom options

Prefer to configure it? Use the spec builder.

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How it works

From enquiry to delivery

Send a part number or describe the application. Our engineers take it from there: the right product, a clear quotation, and delivery and support arranged.

  1. Tell us what you needSend a part number, or configure the application, quantities and timing.
  2. An engineer reviews itWe check the specification and find the original part, a checked equivalent or a complete axis.
  3. Receive your quotationProducts, pricing, lead time and compatibility notes in one reply.
  4. Order and deliveryWhen you are happy, the order is placed and delivery and after-sales support are arranged.