Plain (Sleeve) Bearing Pressure and PV

Projected pressure P = W/(L D) and the PV factor P*V (V = pi D N/12 ft/min), the product that governs frictional heat and wear. An 800 lbf load on a 1 in journal in a 1.5 in bronze bushing at 300 rpm sees 533 psi, 79 ft/min, and PV 41,900 psi-ft/min - just under the ~50,000 limit for oil-impregnated sintered bronze, so it works with little margin; double the speed and PV blows past 83,000, out of range. The projected area L x D is used, not the wrapped area. The hydrodynamic film, temperature rise, and the material specific limits are the bushing maker's. A design aid; Machinery Handbook and the bearing maker govern.

P = W/(L D) (projected area); V = pi D N/12 ft/min; PV = P V. Oil-impregnated sintered bronze PV limit ~50,000 psi-ft/min.

The plain-bearing projected pressure P = W/(L D), surface velocity V = pi D N/12, and the PV factor with the bearing-material PV limits (Machinery's Handbook), by name; the plain-bearing counterpart to the rolling-bearing rating-life tiles.

The projected pressure, surface velocity, and PV factor are standard published plain-bearing results; the load, diameter, length, and speed are the user's inputs, and the rated PV comes from the bushing material.

Estimate. AHJ and licensed professional govern.

Field names used by the API: radial_load_lbf, journal_diameter_in, bearing_length_in, speed_rpm, projected_pressure_psi, surface_velocity_fpm, pv_factor

• Projected pressure P = W/(L D), projected area L x D not wrapped areaMachinery's Handbook
• PV factor PV = P V, must stay under the material's rated PV (~50,000 for oil-impregnated bronze)bearing-material data
• Scope static pressure/PV screen; hydrodynamic film, temperature rise, material limits are the maker'sscope of this tile