Hollow Bearing Blanks BP25

Hollow BP25 bearing blanks are semi-finished, oil-impregnated sintered-bronze tubes supplied for customers who need a bush outside the standard bore, wall or length range. Because the porosity and oil impregnation run right through the wall section, the blank can be turned, bored and faced to a bespoke geometry and the newly machined surfaces remain porous and oil-bearing, preserving the self-lubricating action in the finished part.

Five hollow sizes are offered, with bores from Ø38 to Ø85 mm, outside diameters from Ø70 to Ø175 mm and a common 120 mm length, giving generous stock for machining large or non-catalogue bronze bushings. Take light finishing cuts with sharp tooling to avoid smearing and closing the surface pores, and re-impregnate the machined component with a compatible oil to restore full oil content before service.

• Choose a blank whose bore and outside diameter leave adequate machining allowance around your finished bush dimensions.
• Available sizes (Ø Int. × Ø Ext. × length, mm): 38×70×120, 45×105×120, 80×145×120, 80×175×120, 85×105×120.
• Use BP25 bronze for quiet, corrosion-resistant, moderate-speed duty; for higher load or lower cost consider FP20, and for the alloy grade SO16.
• Finish by light cutting/burnishing and re-impregnate with the matching industrial oil (TURBO T100 for BP25) before fitting.