Wrapped bronze bushings
Thin-walled bushings rolled from cold-formed CuSn8 bronze strip, with diamond-shaped lubricant pockets or through holes in the running surface. The cold work makes the strip hard (110–150 HB) so a 1–2.5 mm wall carries what a cast sleeve several millimetres thick would, at a fraction of the bronze and the price. The standard pivot bearing of agricultural and construction machinery, trailers and lifting equipment.
- 120 N/mm²Static load
- 40 N/mm²Dynamic load
- 1–2.5 mmWall thickness
- Ø10–300 mmStandard bore range
A wrapped bronze bushing is a solid bronze plain bearing made not by machining bar but by blanking a CuSn8 strip, embossing or perforating it with lubricant reservoirs, rolling it into a sleeve with a butt joint and sizing it. It is greased at assembly; the pockets or holes hold the grease and release it as the joint moves.
- Material: homogeneous CuSn8 tin bronze strip, cold formed to 110–150 HB
- JBM-090: diamond-shaped lubricant pockets · JBM-092: through holes for grease from the housing
- JBM-090: 120 N/mm² static, 40 N/mm² dynamic, 2 m/s lubricated, PV 2.8 N/mm²·m/s, −100 to +200 °C, friction 0.08–0.25
- Wall 1–2.5 mm; Ø10–300 mm bore in the ISO 3547 / DIN 1494 dimension series; flanged and thrust-washer forms
- Initial lubrication at assembly required; relubrication interval set by the duty
Two running surfaces, three forms
Pockets or holes, then sleeve, flanged or washer.
JBM-090 · diamond pockets
Embossed pockets act as grease reservoirs that build a film at the start of each movement. The general-purpose type.
PocketsJBM-092 · through holes
Perforated strip: grease fed from the housing passes through the wall to the bore.
HolesFlanged wrapped bushings
Formed flange for axial location and light thrust, ISO 3547 flanged form.
Flanged
Thrust washers
Blanked from the same pocketed strip for axial load.
Axial
Why wrapped instead of cast
Cold-forming CuSn8 strip work-hardens it to 110–150 HB, roughly twice the hardness of cast C93200. That hardness lets a wall of 1–2.5 mm carry 120 N/mm² static and 40 N/mm² dynamic, more than a thick cast sleeve, while using a fraction of the bronze. The thin wall also saves radial space and weight, and the strip process makes tens of thousands of identical parts cheaply. The costs are a smaller range of walls and lengths (set by the strip and tooling), a butt joint that must face away from the load, and a bore that takes its size from the housing rather than from machining.
In service the wrapped bushing behaves like any greased bronze bearing: it wants a hardened or at least clean, smooth shaft, grease at assembly, and a relubrication interval matched to the duty. It tolerates dirt and shock well, which is why it is the standard pivot bearing on ploughs, loaders, cranes, trailers and hydraulic cylinder eyes.
Pockets or holes
JBM-090 has diamond-shaped indents embossed into the running surface. Filled with grease at assembly, they release it as the surfaces move and rebuild the film at every start; the bushing runs for a long interval between greasings and can be used where there is no grease point at all. JBM-092 has through holes instead: grease supplied from a nipple on the housing passes through the wall into the bore, so the bushing can be relubricated in service without any groove machining. Choose 090 for sealed or rarely serviced joints and 092 for joints on a greasing schedule.
| Parameter | JBM-090 (pockets) | Series envelope (catalogue) |
|---|---|---|
| Material | CuSn8, cold formed, 110–150 HB | CuSn8 |
| Static load | 120 N/mm² | 120 N/mm² |
| Dynamic load | 40 N/mm² | — |
| Sliding speed | 2 m/s lubricated | 2.5 m/s |
| PV | 2.8 N/mm²·m/s | — |
| Temperature | −100 to +200 °C | −100 to +200 °C |
| Friction | 0.08–0.25 | 0.05–0.25 |
| Lubrication | Grease at assembly, pockets as reservoir | Grease |
Separate reference limits, not one operating point. JBM-092 data is issued with its drawing.
Fits and installation
The bushing is pressed into an H7 housing; its outside diameter is oversize for the press fit and the bore closes to the running clearance after pressing, so the bore is not machined afterwards. Place the butt joint away from the loaded arc, press with a stepped mandrel and lead the bushing in over a chamfer. Grease the bore and pockets at assembly. Shaft: steel, hardened where the load and dirt justify it, ground or fine-turned; the harder strip is less forgiving of a rough shaft than cast bronze.
Sizes
Standard sleeves, flanged bushings and thrust washers follow the ISO 3547 / DIN 1494 dimension series from Ø10 to Ø300 mm bore in 1–2.5 mm walls. Non-standard lengths are cut from the same tooling; new diameters and walls are a tooling question and are quoted with a minimum batch. For single pieces or thick walls, a machined cast bronze bushing is the better route.
The wrapped bronze size chart lists the ISO 3547 series with wall thickness, fits and chamfers.
What to put in the enquiry
Shaft diameter, housing bore and length (or the ISO 3547 reference), pockets or holes, flange if any, load and motion, greasing arrangement, and quantity. Samples are free; there is no minimum order.
Where wrapped bronze bushings are used
Greased pivots on mobile machinery and equipment made in volume.
Frequently asked questions
What is a wrapped bronze bushing?
A plain bearing rolled from cold-formed CuSn8 bronze strip with lubricant pockets or holes, rather than machined from bar. Thin wall, high hardness, greased at assembly.
Wrapped bronze or cast bronze?
Wrapped for volume, thin walls, 120 N/mm² static and low cost in standard sizes. Cast for single pieces, thick walls, re-machinable bores, large diameters and special alloys.
Do wrapped bronze bushings need grease?
Yes, at assembly; the pockets hold it. JBM-092 with through holes can be relubricated from the housing. Relubrication interval depends on load, motion and dirt.
Are they interchangeable with other ISO 3547 / DIN 1494 wrapped bushings?
The dimension series is the same; interchangeability of a given part is confirmed from the drawing, including wall thickness and pocket type.
What is the difference between JBM-090 and JBM-092?
JBM-090 has embossed diamond pockets as a grease reservoir; JBM-092 has through holes so grease from the housing reaches the bore. Same strip, same sizes.
Send the shaft, the housing and the greasing arrangement.
We confirm pockets or holes, size and fits and quote within 12 hours. Samples are free and there is no minimum order.