C83600, C93200, and C93700 are lead-containing cast copper alloys, but not three versions of one bearing bronze. C83600 is leaded red brass, commonly called 85-5-5-5 or ounce metal. C93200 SAE 660 and C93700 SAE 64 belong to the high-leaded tin bronze family.
Buyers should ask which chemistry and ordered condition fit the load, speed, lubrication, environment, and drawing. None should be treated as a direct substitute without review.
Why C83600, C93200, and C93700 Are Not Direct Equivalents
| Grade | Classification and common name | Nominal chemistry | Typical starting point |
|---|---|---|---|
| C83600 | Leaded red brass; 85-5-5-5; ounce metal | About 85% Cu, 5% Sn, 5% Pb, 5% Zn | Valves, fittings, pump parts, pressure-tight castings, and general components |
| C93200 | High-leaded tin bronze; SAE 660; bearing bronze | About 83% Cu, 7% Sn, 7% Pb, 3% Zn | General industrial bushings and bearings |
| C93700 | High-leaded tin bronze; SAE 64; 80-10-10 bronze | About 80% Cu, 10% Sn, 10% Pb | Bearings exposed to high pressure, speed, contamination, or uncertain lubrication |
The C83600 vs C93200 difference is more than a few percentage points: C83600 contains more zinc and belongs to another classification. In a C93700 vs C93200 comparison, more tin and lead do not make every published strength value higher. Lead supports embeddability and anti-seizing; tin changes hardness, wear, and corrosion behavior. Casting method and section size also matter.
Which Grade Fits the Actual Application?
Start with unit load, speed, lubrication, shaft hardness and finish, temperature, contaminants, corrosion medium, and duty cycle.
C83600 for General Cast Components
C83600 offers good castability, machinability, and general corrosion resistance. It is associated with valves, flanges, fittings, pump components, and hardware. It may suit some moderate-duty sliding parts, but is not a lower-cost equivalent to C93200 or C93700.
Because C83600 contains lead, any potable-water, food-contact, environmental, or customer-specific material restriction must be checked before quotation.
C93200 for General Industrial Bushings
C93200 SAE 660 is a common starting point for leaded bronze bushings. It combines machinability, conformability, embeddability, and resistance to scoring and seizure. Uses include sleeve bearings, thrust washers, wear plates, and lubricated machinery bushings.
“General purpose” does not mean universal. A C93200 bushing can still fail when the shaft is too soft or rough, clearance is wrong, edge loading is high, or the lubricant cannot reach the bearing surface.
C93700 for More Demanding Bearing Conditions
C93700 is evaluated for high-speed or high-pressure bearings, large bushings, pumps, steel-mill parts, and service where dirt may enter or lubrication may be interrupted. Its lead can embed small particles and protect the mating shaft.
That is not permission to run the bearing without lubrication. It also does not prove that C93700 is automatically an upgrade from C93200. The required load capacity, elongation, shaft compatibility, inspection, and governing specification must support the change.
What Must Be Confirmed Before Substituting One Grade for Another?
Searches for a C83600 equivalent, C93200 equivalent, or C93700 equivalent return historical names and cross-references. Use them for identification, not automatic substitution.
Confirm the drawing, UNS grade, ASTM or SAE specification, casting route, ordered condition, minimum properties, dimensions, machining allowance, and inspection documents. ASTM B271/B271M covers centrifugal castings; ASTM B505/B505M covers continuous cast rod, bar, tube, and shapes. Centrifugal and continuous cast bronze can have different blank forms and ordered properties under one UNS number.
A supplier should never replace one grade silently because its common name or nominal composition appears similar. Any material change needs documented engineering or customer approval.
Send Your Drawing for Alloy and Casting Review
Send JEDBUSHING the drawing, current material designation, quantity, load, speed, lubrication, shaft details, operating medium, temperature, and required documents.
We can review the alloy, casting route, blank dimensions, machining allowance, and inspection plan before quotation. Contact JEDBUSHING about a new or replacement bushing.
Frequently Asked Questions
Can a worn bushing be identified as C83600, C93200, or C93700 by hardness alone?
No. Hardness ranges can overlap and wear can change the test surface. Positive identification normally requires representative chemical analysis against the applicable UNS composition limits.
Does the higher lead content of C93700 make it self-lubricating?
No. Lead improves conformability, embeddability, and anti-seizing behavior, but it does not provide a renewable lubricant supply. The lubrication method and operating limits must still be defined.
Can JEDBUSHING quote both a rough casting and a finished bushing from the same drawing?
Yes. Identify the required blank dimensions, machining allowance, reference surfaces, final dimensions, inspection points, and whether material or test documents must accompany each supply condition.
What if an old drawing specifies SAE 660 or SAE 64 instead of a UNS number?
Keep the original designation on the inquiry. SAE 660 commonly points to C93200 and SAE 64 to C93700, but the applicable standard, composition, casting condition, and required properties should be confirmed before production.