Babbitts
Description
Modern babbitts provide a low-friction lining for bearing shells made of stronger metals such as cast iron, steel, or bronze. They may be made of high-tin alloys with small quantities of antimony and copper; high-lead alloys containing antimony, arsenic, and tin; or intermediate tin-lead alloys with antimony and copper. The small quantities of hard metal in a soft matrix of tin or lead create a material strong enough to bear relatively high speeds and loads yet soft enough to embed dirt or other intrusions and not seize up on a spinning shaft in case of lubrication failure.
Tin-based babbitt has high thermal connectivity allowing heat to be transported away from your equipment. This trait means there will be fewer issues with equipment overheating or breaking down. Because it can flow well even in high-pressure situations, it is useful for machinery that is not properly lubricated along the shafts and bearings. Tin-based babbitt is commonly used for farm machinery, conveyors, elevator applications, and general machinery.
Lead-base babbitt can withstand shock and vibration and requires less lubrication than other types of babbitt. Use it to cast bearings for low-speed, heavy-load applications. For bearings, it is excellent for moderate cyclic loads and unidirectional loads. Since lead-base babbitt is corrosion-resistant, it can be used aboard sea-vessels or underwater.
Canfield babbitt, like all our alloys, exceed ASTM standards. It is available in 8, 25, or 50 lb. ingots. Grade 2 babbitt is also available in .187 and .125 diameter wire packaged on 25 lb. spools or in 200 lb. POPs.
ASTM B-32 | Tin Base | |||
Elemental Composition % | Grade 1 | Grade 2 | Grade 3 | Grade 11 |
Tin | 90.0 – 92.0 | 88.0 – 90.0 | 83.0 – 85.0 | 86.0 – 89.0 |
Antimony | 4.0 – 5.0 | 7.0 – 8.0 | 7.5 – 8.5 | 6.0 – 7.5 |
Lead | 0.35 | 0.35 | 0.35 | 0.5 |
Copper | 4.0 – 5.0 | 3.0 – 4.0 | 7.5 – 8.5 | 5.0 – 6.5 |
Iron | 0.08 | 0.08 | 0.08 | 0.08 |
Arsenic | 0.1 | 0.1 | 0.1 | 0.1 |
Bismuth | 0.08 | 0.08 | 0.08 | 0.08 |
Zinc | 0.005 | 0.005 | 0.005 | 0.005 |
Aluminum | 0.005 | 0.005 | 0.005 | 0.005 |
Cadmium | 0.05 | 0.05 | 0.05 | 0.05 |
ASTM B-32 | Lead Base | |||
Elemental Composition % | Grade 7 | Grade 8 | Grade 13 | Grade 15 |
Tin | 9.3 – 10.7 | 4.5 – 5.5 | 5.5 – 6.5 | 0.8 – 1.2 |
Antimony | 14.0 – 16.0 | 14.0 – 16.0 | 9.5 – 10.5 | 14.5 – 17.5 |
Lead | Remainder | Remainder | Remainder | Remainder |
Copper | 0.5 | 0.5 | 0.5 | 0.5 |
Iron | 0.1 | 0.1 | 0.1 | 0.1 |
Arsenic | 0.30 – 0.60 | 0.30 – 0.60 | 0.25 | 0.8 – 1.4 |
Bismuth | 0.1 | 0.1 | 0.1 | 0.1 |
Zinc | 0.005 | 0.005 | 0.005 | 0.005 |
Aluminum | 0.005 | 0.005 | 0.005 | 0.005 |
Cadmium | 0.05 | 0.05 | 0.05 | 0.05 |