MG-2Y cylindrical bushings are lead-free boundary lubricated bearings manufactured with a low-carbon steel backing, a sintered porous bronze powder interlayer, and a POM (polyoxymethylene) fiber-filled polymer surface. This bimetal composite design provides high load capacity, good wear resistance, and low friction. The bearings are suitable for rotary, oscillating, and reciprocating movements under high load and low to medium speed conditions. The POM surface can be supplied with lubrication indents to retain grease, allowing the bearing to operate for extended periods without external oiling.
◆ Material Structure
MG-2Y cylindrical bushings consist of four distinct layers:
1. POM with fiber – 0.3~0.5mm. Polyoxymethylene filled with fiber reinforcement provides low friction, high stiffness, and excellent wear resistance.
2. Porous bronze powder – 0.2~0.35mm. Sintered spherical bronze layer creates a strong mechanical bond to the steel backing and acts as a reservoir for the POM polymer.
3. Steel backing – 0.4~2.2mm. Low-carbon steel strip provides high mechanical strength and structural integrity for press-fit installation.
4. Plated coating – Tin plating 0.005mm or copper plating 0.008mm for corrosion resistance.
◆ Operating Parameters (Technical Data)
| Technical Data – MG-2Y Cylindrical Bushings | |
| Max. static load | 250 N/mm² |
| Max. load (very low speed) | 140 N/mm² |
| Max. load (rotating / oscillating) | 70 N/mm² |
| Max. PV (dry running) | 3 N/mm²·m/s |
| Temperature range | -40°C to +110°C |
| Friction coefficient | 0.05 ~ 0.20 |
| Max. speed (grease lubrication) | 2 m/s |
| Max. speed (oil lubrication) | >2 m/s |
| Thermal conductivity | 50 W/(m·K) |
| Coefficient of thermal expansion | 11 × 10⁻⁶ /K |
◆ Tolerance Data (ISO 3547 / Equivalent)
MG-2Y bushings conform to ISO 3547 standard specifications for wrapped plain bearings. As flexible components, free-state dimensions differ from installed dimensions. The following tolerance data is specified for assembled (press-fit) condition.
| Nominal Diameter Range (mm) | Shaft (f7) Tolerance (mm) | Housing (H7) Tolerance (mm) | Bushing OD after Press-fit (mm) | Bushing ID after Press-fit (mm) |
|---|---|---|---|---|
| 14 (e.g., shaft dia 14) | -0.016 / -0.043 | +0.018 / 0 | +0.018 / +0.014 | +0.065 / +0.030 |
| 18~30 | -0.020 / -0.053 | +0.021 / 0 | +0.025 / +0.009 | +0.085 / +0.045 |
| 30~50 | -0.025 / -0.064 | +0.025 / 0 | +0.033 / +0.013 | +0.085 / +0.045 |
| 80~120 | -0.036 / -0.090 | +0.035 / 0 | +0.040 / +0.011 | +0.170 / +0.100 |
| 170 (e.g., shaft dia 170) | -0.063 / -0.143 | +0.040 / 0 | +0.040 / +0.011 | +0.170 / +0.100 |
◆ Fit Recommendations
For optimal press-fit installation and reliable operation, the following fit recommendations should be observed:
Housing bore: H7 tolerance (e.g., +0.025 / 0 for 30~50 mm range)
Shaft: f7 tolerance (e.g., -0.025 / -0.064 for 30~50 mm range)
Bushing OD after press-fit: Provides interference fit with housing
Bushing ID after press-fit: Provides clearance fit with shaft for proper lubrication film
Initial pre-lubrication: Assembly strongly recommended – lubrication grease must be fully applied into oil pockets
◆ Available Forms
MG-2Y bearings are available in various configurations:
● Cylindrical bushings (standard and custom lengths)
● Flanged bushings (MG-2Y WC series)
● Thrust washers and wear plates
● Custom sizes and non-standard configurations per customer specifications
◆ Application Areas
MG-2Y cylindrical bushings are widely used in applications requiring high load capacity and low speed with rotating, oscillating or frequent stop-start motion. Typical industries include:
● Metallurgy machinery and steel rolling industry
● Mining machinery and construction equipment
● Water conservancy machinery and hydropower equipment
● Automobile chassis and automotive components
● Agricultural machinery and heavy machinery
● Forging machines, power stations, and civil engineering applications
