Precisely ground glass beads are mainly used in the optical industry. They are also used in the chemical, food, and pharmaceutical industries, primarily in check valves and bearings. They are manufactured by grinding on abrasive wheels, a method called lapping.
Precisely ground beads are made from both soda-lime glass and borosilicate glass, which are used, for example, in valves in the chemical or pharmaceutical industries.
Rarely, beads are also ground from colored glass (e.g., valve bead in insemination doses) or even multicolored beads, which are used in sight flow meters for clear liquids.
| Usage: | check valves, pumps, bearings, optics |
|---|---|
| Size: | 2–40 mm |
| Tolerance: | standard +/- 0.02 (on request more precise up to +/- 0.002) |
| Surface: | matte, fine matte, gloss only by agreement |
| Glass: | soda-lime, borosilicate |
Valve and bearing beads
In the manufacture of valves and bearings used in technologies in the chemical, food, or pharmaceutical industries, glass beads are often used. These beads, due to their specific properties, mainly resistance to aggressive liquids, replace metal beads.
Two main parameters are monitored in the production of these beads:
- glass properties – borosilicate glass is very often used for its hardness, compressive strength, and high resistance to acids and alkalis (1st hydrolytic class)
- grinding precision – beads are ground using lapping technology, just like metal beads. Achieved precision is in the order of thousandths of a millimeter both in diameter tolerance and bead roundness. According to customer requirements, a defined surface is prepared – smooth (gloss) or defined roughness (matte).
