C93200 / SAE 660 (RG7) bronze bushings
The general-purpose bearing bronze: 83 % copper, 7 % tin, 7 % lead, 3 % zinc. SAE 660, UNS C93200, CDA 932 and ASTM B505 C93200 are one alloy; RG7 / Rotguss and CuSn7Zn4Pb7-C (EN 1982 CC493K) are the European casting of the same composition. The lead gives emergency lubrication and embeds dirt, the tin gives strength, and 65 – 75 HB lets it run on an unhardened steel shaft. Default alloy for every standard size on this site; the high-lead relatives C93700 / SAE 64 and C93800 / SAE 67 are covered on this page too.
C93200 is a high-leaded tin bronze cast continuously (ASTM B505, bores to about Ø180 mm) or centrifugally (ASTM B271, larger sizes) and machined into bushings. It is the alloy meant when a drawing says "bearing bronze", "SAE 660" or "RG7" without further data.
- Composition (ASTM B505): Cu 81.0 – 85.0, Sn 6.3 – 7.5, Pb 6.0 – 8.0, Zn 1.0 – 4.0, Ni ≤ 1.0 %
- Minimums (B505): tensile 207 N/mm² (30 ksi), yield 110 N/mm² (16 ksi), elongation 8 %; typical 240 / 125 N/mm², 15 – 20 %, 65 – 75 HB
- Density 8.93 g/cm³, machinability 70 (C36000 = 100), no dezincification, −40 to +250 °C
- Runs on plain steel shafts of 150 – 200 HB; tolerates short lubrication gaps and dirty grease
- Contains 7 % lead – not for drinking-water or food-contact positions; lead-free alternatives CuSn12 / CuSn10
Chemical composition
C93200 / SAE 660 · CuSn7Zn4Pb7
| Element | Range (% by mass) | Nominal (%) |
|---|---|---|
| Cu | 81.0–85.0 | 83 |
| Sn | 6.3–7.5 | 7 |
| Pb | 6.0–8.0 | 7 |
| Zn | 1.0–4.0 | 3 |
| Ni | ≤ 1.0 | — |
Composition and minimum properties per ASTM B505; typical values as cast.
C93700 / SAE 64 · CuSn10Pb10
| Element | Range (% by mass) | Nominal (%) |
|---|---|---|
| Cu | 78.0–82.0 | 80 |
| Sn | 9.0–11.0 | 10 |
| Pb | 8.0–11.0 | 10 |
| Zn | ≤ 0.8 | — |
| Ni | ≤ 0.5 | — |
* Typical values per ASTM B505 / B271, EN 1982 and GB/T 1176 for the cast alloy; not a guarantee for a specific part. Test certificates (chemical analysis, hardness) are supplied on request with the order.
C93800 / SAE 67 · CuSn7Pb15
| Element | Range (% by mass) | Nominal (%) |
|---|---|---|
| Cu | 75.0–79.0 | 77 |
| Sn | 6.3–7.5 | 7 |
| Pb | 13.0–16.0 | 15 |
| Zn | ≤ 0.8 | — |
| Ni | ≤ 1.0 | — |
* Typical values per ASTM B505 / B271, EN 1982 and GB/T 1176 for the cast alloy; not a guarantee for a specific part. Test certificates (chemical analysis, hardness) are supplied on request with the order.
Tensile strength · Hardness · Density
| Grade | Alloy | Family | Tensile strength standard minimum (MPa) | Yield strength (0.5 % ext. / Rp0.2) standard minimum (MPa) | Elongation (%) | Hardness (HB) | Tensile strength typical (MPa) | Density (g/cm³) | Machinability (C36000 = 100) |
|---|---|---|---|---|---|---|---|---|---|
| C93200 / SAE 660 | CuSn7Zn4Pb7 | leaded tin bronze | 207 | 110 | 8 | 65–75 | 240 | 8.93 | 70 |
| C93700 / SAE 64* | CuSn10Pb10 | leaded tin bronze | 241 | 138 | 6 | 60–70 | 240 | 8.95 | 80 |
| C93800 / SAE 67* | CuSn7Pb15 | leaded tin bronze | 172 | 110 | 5 | 50–60 | 207 | 9.25 | 80 |
* Typical values per ASTM B505 / B271, EN 1982 and GB/T 1176 for the cast alloy; not a guarantee for a specific part. Test certificates (chemical analysis, hardness) are supplied on request with the order.
Also known as
| Parameter | C93200 / SAE 660CuSn7Zn4Pb7 | C93700 / SAE 64CuSn10Pb10 | C93800 / SAE 67CuSn7Pb15 |
|---|---|---|---|
| UNS / ASTM | C93200 | C93700 | C93800 |
| SAE | SAE 660 | SAE 64 | SAE 67 |
| EN 1982 | CuSn7Zn4Pb7-C · CC493K | CuSn10Pb10-C · CC495K | CuSn7Pb15-C · CC496K |
| DIN (old) | Rg7 · 2.1090 | CuPb10Sn · 2.1176 | CuPb15Sn · 2.1182 |
| BS 1400 | — | LB2 | LB1 |
| JIS H5120 | — | CAC603 (LBC3) | CAC604 (LBC4) |
| GB/T 1176 | — (cast to ASTM; nearest ZCuSn5Pb5Zn5) | ZCuPb10Sn10 | ZCuPb15Sn8 |
| ГОСТ 613 | — (nearest БрО5Ц5С5) | БрО10С10 | БрО8С12 (nearest) |
| PN (Poland) | — (RG7 is quoted; nearest B555) | B1010 | B1510 (verify) |
| Also known as | CDA 932 · 83-7-7-3 · Rg7 (DE) · RG-7 (ES) · UE7 (FR) · B7 (IT, withdrawn) · "bronze grafitado" (BR trade name) | CDA 937 · 80-10-10 · AFNOR U-Pb10E10 | CDA 938 · 78-7-15 · nearest standard grade to Brazilian TM 23 (Pb 15–18 %) |
* Typical values per ASTM B505 / B271, EN 1982 and GB/T 1176 for the cast alloy; not a guarantee for a specific part. Test certificates (chemical analysis, hardness) are supplied on request with the order.
Equivalent grades – which are the same alloy and which are not
Buyers meet C93200 under a dozen names. Some are the same composition cast to another standard and interchangeable; some are neighbours that behave similarly but differ in chemistry; one is a trade name that is frequently, and wrongly, treated as equal.
| Designation | System | Relation to C93200 |
|---|---|---|
| SAE 660 | SAE J461 / J462 (USA) | same alloy – the old SAE number of C93200 |
| UNS C93200 · CDA 932 · ASTM B505 / B271 / B584 C93200 | UNS / ASTM (USA) | same alloy – continuous cast (B505), centrifugal (B271), sand (B584) |
| CuSn7Zn4Pb7-C · CC493K | EN 1982 (Europe) | same composition; EN minimums Rm 260 / Rp0.2 120 N/mm², A 12 %, 65 HB (GZ / GC) |
| Rg7 · 2.1090 · G-CuSn7ZnPb | DIN 1705 (Germany, withdrawn) | same alloy – "Rotguss 7"; also RG-7 in Spain, RG7 in Poland and Turkey |
| UE7 | AFNOR (France, old) | same class – leaded tin bronze 7 % Sn |
| B7 · "bronzo B7" | UNI (Italy, withdrawn 1978) | same class; today CC493K. B14 is CuSn12, not this alloy |
| LG2 · C83600 · CuSn5Zn5Pb5 | BS 1400 / UNS / EN CC491K | not the same – 5-5-5 gunmetal, lower tin, sold alongside 660 in Australia and the UK; interchangeable for light duty only |
| CAC406 (BC6) | JIS H5120 (Japan) | not the same – it is the 5-5-5 gunmetal (= LG2); the Japanese near-equivalent to 660 duty |
| ZCuSn5Pb5Zn5 | GB/T 1176 (China) | nearest GB grade (5-5-5); Chinese foundries cast C93200 to ASTM directly |
| TM 23 · TM 620 | Termomecânica (Brazil, trade names) | not equivalent – TM 23 has 15 – 18 % lead (near C93800 / SAE 67); TM 620 is a tin bronze near C90500 |
| C93700 / SAE 64 · CuSn10Pb10 · CC495K | UNS / EN | relative – 10 % lead, for poor lubrication; see below |
| C93800 / SAE 67 · CuSn7Pb15 · CC496K | UNS / EN | relative – 15 % lead, for the worst lubrication; see below |
For your enquiry:Drawing says RG7, TM 23, LG2 or CAC406? Send it – we confirm which grade it is and quote it.
Chemical composition and mechanical properties
The tables below are printed from the casting standards: ASTM B505 ranges and minimums for C93200, C93700 and C93800, with the typical as-cast values the Copper Development Association publishes. Casting method and wall thickness shift the actual values; the material certificate of the stock is what counts for a batch.
Physical properties of C93200: density 8.93 g/cm³ (0.322 lb/in³), coefficient of thermal expansion 18 × 10⁻⁶ /K (20 – 200 °C), thermal conductivity about 58 W/(m·K), modulus of elasticity about 100 GPa, machinability rating 70. It is not heat-treatable; strength falls off above 250 °C and the alloy is used to that temperature only.
When to use C93200 – and when not
Use it for grease-lubricated pins, pivots and slow shafts in construction and agricultural machinery, pumps, valves, machine tools, presses, conveyors and hydraulic cylinders, wherever the shaft is plain steel and relubrication happens. It is the cheapest durable choice and the easiest to machine and re-bore.
Do not use it above 250 °C, under repeated heavy shock (the soft matrix flows – take C86300 or aluminium bronze), in seawater or acid process water (aluminium bronze, gunmetal), where lead is excluded (CuSn12, CuSn10, C90500), or where lubrication is missing for long periods (C93700 / SAE 64 tolerates it better; graphite-plugged bushings run without it).
| Criterion | C93200 / SAE 660 | C93700 / SAE 64 | C86300 | Aluminium bronze C95400 |
|---|---|---|---|---|
| Min. tensile, N/mm² | 207 | 241 | 758 | 586 |
| Hardness HB | 65 – 75 | 60 – 70 | 225 | 170 |
| Load | medium | medium, lower than 660 | extreme | high |
| Speed under grease | to 0.5 m/s | to 0.5 m/s, tolerates dry spells | very low | low – medium with oil |
| Shock | moderate | good | excellent | very good |
| Corrosion | fresh water, mild | mildly acidic mine water | dezincification risk in warm saline | seawater, erosion |
| Machinability | 70 | 80 | 8 | 60 |
| Shaft | plain steel 150 HB | plain or slightly rough steel | hardened 300 HB+ | hardened 300 HB+ |
| Cost | reference | slightly higher | about 2× | about 1.5× |
SAE 64, 65, 62, 67 and 660 – what the numbers mean
Latin American, Brazilian and older US drawings specify bearing bronzes by SAE number. The numbers are not a series – they are unrelated alloys from three families. C93700 / SAE 64 and C93800 / SAE 67 are in the Slidura programme and are machined into every form on this site; SAE 65 and SAE 62 are covered by our tin bronzes.
| SAE | UNS | Alloy | Character | European equivalent |
|---|---|---|---|---|
| SAE 660 | C93200 | CuSn7Zn4Pb7 (83-7-7-3) | general-purpose bearing bronze | CC493K · RG7 |
| SAE 64 | C93700 | CuSn10Pb10 (80-10-10) | high-lead: poor lubrication, shock, mildly acidic water; softer than 660 | CC495K · CuPb10Sn 2.1176 · ГОСТ БрО10С10 · PN B1010 |
| SAE 67 | C93800 | CuSn7Pb15 (78-7-15) | very high lead: worst lubrication, rough shafts, high speed at low load | CC496K · CuPb15Sn 2.1182 · nearest to TM 23 |
| SAE 65 | C90700 / C90710 | CuSn11 / CuSn10P (phosphor bronze) | hard, wear-resistant, lead-free; needs oil and a hard shaft | CC481K CuSn11P · B101 · PB1 – our CuSn10P |
| SAE 62 | C90500 | CuSn10Zn2 (88-10-2, G bronze) | gear bronze: strong, tough, lead-free | nearest CuSn10-C CC480K · G1 · ZCuSn10Zn2 – our C90500 |
| SAE 40 | C83600 | CuSn5Zn5Pb5 (85-5-5-5) | leaded gunmetal for water and light load | CC491K · LG2 · Rg5 · CAC406 |
SAE 64 vs SAE 660: SAE 64 has 10 % lead instead of 7 %, is a little softer and tolerates interrupted lubrication and shock better; 660 carries slightly more load and is the general choice when grease is reliable. Neither is "stronger" in the sense a buyer usually means – pick by lubrication quality.
Lead content and regulations
C93200 (7 % Pb), C93700 (10 %) and C93800 (15 %) exceed the 4 % lead exemption for copper alloys in RoHS and the End-of-Life Vehicles directive, the 0.25 % weighted limit of the US Safe Drinking Water Act (NSF/ANSI 61 and 372) and the usual food-contact limits, and they require a REACH SVHC notification above 0.1 %. In industrial machinery bearings they remain permitted and are the standard alloys. Where lead is excluded, the lead-free tin bronzes CuSn12, CuSn10 and C90500 or the aluminium bronzes replace them; we quote both when asked.
Where C93200 bushings are used
The alloy behind most of the standard sizes shipped from Jiaxing:
- Construction machinery: boom, bucket and steering pins, cylinder eyes (C86300 for the heaviest)
- Agricultural machinery: linkage pivots, header and baler bushes, trailer axle bushes
- Pumps and valves: shaft bushes, wear rings, stem guides (LG2 where water dominates)
- Machine tools, presses, conveyors, textile and packaging machinery: slow shafts and guides
- Hydraulic cylinders: rod-eye and gland bushes
- Steel and sugar mills: table roller and roll-neck bushes to Ø600 mm (SAE 64 for poorly lubricated shafts)
Forms and sizes in C93200
Sleeve and flanged bushings to ISO 4379 Ø6 – 200 mm, thrust washers Ø12 – 200 mm shaft, and parts to drawing to Ø1000 mm. C93200 tube is the most readily available; SAE 64 and SAE 67 bar and tube are bought per order.
Frequently asked questions
Are SAE 660 and C93200 the same?
Yes. SAE 660 is the SAE J461 / J462 designation, C93200 the UNS number, CDA 932 the Copper Development Association number – one alloy, 83-7-7-3 leaded tin bronze. ASTM B505 (continuous cast) and B271 (centrifugal cast) are the standards our stock is bought to.
What is the European equivalent of SAE 660?
CuSn7Zn4Pb7-C, EN 1982 number CC493K, better known by the old DIN name Rg7 (Rotguss 7, material number 2.1090). Same composition, cast to the EN standard; Rg7 / RG-7 is what Spanish, Polish, Turkish and German drawings write.
Is TM 23 the same as SAE 660?
No. TM 23 is a Termomecânica (Brazil) alloy with 15 – 18 % lead; SAE 660 has 6 – 8 %. Termomecânica itself says only that TM 23 behaves like the leaded bearing bronzes, not that it is chemically equal. The nearest standard grade to TM 23 is C93800 / SAE 67 (CuSn7Pb15), which we machine.
What is the density of SAE 660?
8.93 g/cm³ (0.322 lb/in³). A Ø50 × Ø60 × 60 mm sleeve therefore weighs about 0.46 kg; the size chart shows the weight of every standard size for freight and per-kilogram pricing.
How machinable is C93200?
Very – rating 70 against 100 for free-cutting brass. The lead breaks the chip and lubricates the tool, which is why 660 bushes are cheap to bore and re-bore. C93700 rates 80, C86300 only 8.
Is SAE 660 lead-free?
No – it contains 6 – 8 % lead by design. For lead-restricted positions (drinking water, food machinery, some OEM material lists) we machine the same sizes in CuSn12, CuSn10, C90500 or aluminium bronze.
Quote C93200 bushings – standard sizes or to drawing
Send the order code or d × D × L, quantity and whether you need the ASTM B505 or EN 1982 certificate.