GK1256 Series – Through Bore Slip Rings
The GK1256 is a through-bore slip ring: the shaft passes straight through the hollow centre, so cables can be routed down the bore and the unit mounts rigidly on the rotating shaft. This model provides 12.7 mm bore, 56 mm OD, 6/12/18/24/36 circuits, 440 V, available in IP51, IP65 and IP68 versions and rated −30 to +80 °C.
Typical applications: rotary tables, packaging and filling machinery, cable reels and winches, wind turbine nacelles, and industrial test stands where continuous rotation is required.
Selection notes: current per ring depends on bore size — 5 A or 10 A at 12.7 mm and up to 20 A per ring from 25.4 mm upward. Above 15 A on a small bore, parallel rings are the practical solution. Life expectancy for this family is offered in three tiers: 20, 50 and 80 million revolutions.
GUREN machines, assembles and dielectric-tests through-bore slip rings in-house, including a full insulation test on every unit before shipment.
Custom circuit counts, lead lengths, connector types and mounting flanges are quoted on request, and in-house machining keeps lead times short for both standard and modified units.
Bore-size guide: see all 12.7 mm bore slip rings, including selection notes and current limits for this size.
Specifications — GK1256
| Parameter | Value |
|---|---|
| Bore (inner diameter) | 12.7 mm |
| Outer diameter | 56 mm |
| Circuits | 6 / 12 / 18 / 24 / 36 |
| Current per ring | 5 A / 10 A |
| Rated voltage | 0-440 VDC/VAC |
| Dielectric strength | 800VAC@50Hz 60s (power) / 300VAC@50Hz 60s (signal) |
| Insulation resistance | ≥ 1000 MΩ/500VDC (power) / ≥ 1000 MΩ/300VDC (signal) |
| Dynamic contact resistance | < 10 mΩ |
| Operating temperature | -30 °C ~ +80C |
| Protection | IP51 standard; IP65 / IP68 available |
| Lead wire | AF200-17AWG Teflon, default length 300mm (adjustable) |
| Length by circuit count | 35.4 mm (6 ckt) / 51.6 mm (12 ckt) / 67.8 mm (18 ckt) / 84 mm (24 ckt) / 116.4 mm (36 ckt) |
| Life / max speed (D1 / D2 / D3) | 20 M rev @ 250 rpm · 50 M rev @ 800 rpm · 80 M rev @ 1200 rpm |
Figures above are from the current datasheet for this series. Customisation of bore, circuit count, lead length and mounting is quoted per drawing.
Frequently asked questions — GK1256
What are the bore and outer diameter of the GK1256?
12.7 mm bore and 56 mm outer diameter.
How many circuits and how much current per ring?
Standard counts: 6 / 12 / 18 / 24 / 36. Per-ring current: 5 A / 10 A.
Which ingress protection classes are available?
IP51 is standard; IP65 and IP68 versions are available for washdown, outdoor and high-humidity service.
What life expectancy can I expect?
Three grades: D1 20 million rev at 250 rpm, D2 50 million rev at 800 rpm, D3 80 million rev at 1200 rpm.
