Maintenance-free operation in rotating and oscillating equipment often requires a bearing element that performs reliably without external grease or oil. The self lubricating bronze PTFE bearing bushing is designed for these dry-running conditions, combining the structural strength of bronze with the low friction of PTFE. When installed as a bronze filled PTFE bushing for rotating shaft, it forms a thin solid lubricant film on the shaft surface, reducing stick-slip, wear, and noise during start-up and continuous rotation. For pivot points, agricultural implements, and construction machinery that experience high radial loads at slow speeds, the PTFE bronze bushing heavy duty configuration offers a denser bronze matrix, higher compressive strength, and extended service life under edge loading. As a specialized bronze filled PTFE bushing manufacturer, we monitor porosity, lubricant distribution, and machining tolerance to deliver consistent performance in series production and aftermarket replacement. The finished component is a wear resistant PTFE bushing with bronze that works well in dusty, wet, or hard-to-reach locations where regular lubrication is impossible.
The self lubricating bronze PTFE bearing bushing is manufactured by sintering spherical bronze powder into a porous sleeve and then vacuum-impregnating the pores with a PTFE and graphite compound. This structure stores solid lubricant inside the bronze wall and releases it gradually during operation as the mating shaft slides. It removes the need for grease fittings, oil grooves, or periodic re-lubrication, which reduces maintenance time and the risk of contamination in food, textile, and packaging machinery. The bronze skeleton provides high thermal conductivity and dimensional stability under load, while the embedded PTFE surface delivers a stable low friction coefficient of 0.03 to 0.12 in dry conditions. During initial run-in, the PTFE layer transfers to the shaft and forms a low-shear film. Graphite particles embedded in the lubricant help reduce friction at high load and low speed. The bushing also resists galvanic corrosion when paired with steel shafts because the bronze matrix maintains stable contact resistance. In moist environments, the material shows excellent resistance to washout, making it suitable for marine and outdoor equipment. This bushing is available in cylindrical, flanged, and thrust washer forms, and can be machined to custom sizes for OEM applications. A fine-turned or ground shaft with surface hardness of HRC 45 or higher is recommended. The housing bore should be chamfered 15° to 30° to assist pressing. Clean the bore before installation, and use a piloted arbor press to avoid damage to the PTFE surface. For heavy-duty applications, a steel backing may be added to improve interference fit retention. The bushing can also be supplied with lubrication grooves if occasional oil or grease is available, but dry operation remains fully supported by the embedded solid lubricant.
| Parameter | Unit | Typical Value |
|---|---|---|
| Bronze base material | - | CuSn6-6-3 / CuSn10 |
| Solid lubricant | - | PTFE + graphite |
| Density | g/cm³ | 7.8 – 8.2 |
| Hardness | HB | 70 – 100 |
| Max dynamic load | N/mm² | 140 |
| Max static load | N/mm² | 250 |
| Max sliding velocity dry | m/s | 2.5 |
| Max PV value dry | N/mm²·m/s | 3.6 |
| Coefficient of friction dry | - | 0.03 – 0.12 |
| Temperature range | °C | -200 to +280 |
| Thermal conductivity | W/(m·K) | 47 – 52 |
| Linear expansion coefficient | 10⁻⁶/K | 17 – 19 |
| Inner Diameter Range | Outer Diameter Range | Length Range | Typical Application |
|---|---|---|---|
| 5 – 20 mm | 8 – 28 mm | 10 – 30 mm | Textile guides, small idler rollers |
| 20 – 50 mm | 28 – 60 mm | 20 – 60 mm | Agricultural linkage pivots |
| 50 – 100 mm | 60 – 120 mm | 40 – 100 mm | Hydraulic cylinder mounts |
| 100 – 200 mm | 120 – 230 mm | 60 – 150 mm | Construction equipment joints |
