Cast Bronze Sleeve Bushings | C93200 (SAE 660)

Yes. C93200 is the UNS (Unified Numbering System) designation; SAE 660 is the SAE International designation. Both refer to the same 83-7-7-3 high-leaded tin bronze alloy. You'll also see it called CDA 932 (Copper Development Association) or simply "bearing bronze." All are equivalent and interchangeable when specifying material.

C93200 is the better choice for general-purpose bearing applications with adequate lubrication, moderate loads (up to 4,000 PSI), and moderate speeds (up to 750 SFM). It machines easily and costs less than aluminum bronze.

Choose C95400 when you need higher strength (85,000 PSI tensile vs. 44,000 PSI), superior corrosion resistance, or exposure to seawater or marine environments. C95400 also handles higher loads but requires better shaft hardness and more careful attention to lubrication.

Standard practice is 0.001" of clearance per inch of shaft diameter for shafts up to 5". For example: a 2" shaft gets 0.002" clearance; a 3" shaft gets 0.003" clearance.

Larger shafts (over 5") typically use proportionally less clearance. High-speed applications may need additional clearance; heavy or unidirectional loads may work with slightly less clearance. These are starting points—adjust based on your operating conditions.

The shaft should be harder than the bushing to prevent galling and ensure the bushing wears preferentially (bushings are easier to replace than shafts). A minimum of 35 HRC works well with C93200.

Common shaft materials include hardened 4140 steel, 410 stainless steel, and other through-hardened or case-hardened steels. Soft shafts or shafts with poor surface finish will cause premature bushing wear.

PV is Pressure × Velocity—the standard measure of bearing load capacity. C93200 has a maximum PV of 75,000 psi-fpm.

To calculate your application's PV:

• P (pressure) = Load (lbs) ÷ Projected Area (ID × bearing length, in square inches)
• V (velocity) = 0.262 × RPM × shaft diameter (inches)
• PV = P × V

If your calculated PV exceeds 75,000, you'll need a larger bearing, a different alloy, or improved lubrication.

C93200 handles continuous operating temperatures up to 500°F (260°C). Above this, the lead in the alloy begins to soften, reducing load capacity.

For high-temperature applications, graphite-plugged bushings help by providing dry lubrication as conventional oils and greases break down. If your application regularly exceeds 500°F, consider aluminum bronze (C95400) which handles higher temperatures.

Often, yes. Pressing a bushing into a housing compresses the ID by approximately 70–100% of the interference fit. For example, if you use 0.002" interference on the OD, the ID may shrink by 0.0014–0.002".

If final ID tolerance is critical, machine the bushing ID to allow for this compression, then ream or bore to final size after installation. This is standard practice for precision applications.

Yes. For applications requiring RoHS or REACH compliance, C89835 (Bismuth Tin Bronze) and C87850 (ECO Bronze) offer comparable bearing performance without lead. Bismuth replaces lead as the internal lubricant and machinability enhancer.

If your application requires lead-free material, contact us with your requirements. Lead-free alternatives typically have longer lead times and higher cost than standard C93200.