The scarce core
Gas Bearings
Aerostatic (orifice, slot-fed and porous), spiral-groove and narrow-groove gas bearings — plus the closely related hydrostatic (liquid-film) bearings. This is the material with the fewest alternatives anywhere — there is no free calculator for spiral-groove bearings elsewhere, and general bearing suites do not cover aerostatic design.
Gas bearing design sits at the specialist end of precision engineering. The theory for spiral-groove bearings traces back to Muijderman’s narrow-groove work (Philips Research Reports, 1964); the aerostatic calculators here encode design relations that are otherwise scattered across out-of-print sources.
All 27 scarce aerostatic/gas- and spiral-groove-bearing models are migrated and validated against the original — this is the part of the migration that got the most care. The 13 hydrostatic-bearing calculators shown below are semi-scarce rather than scarce (a handful of alternatives exist), but sit in the same externally-pressurized-film family.
Calculators
Aerostatic thrust bearing — simple orifice restrictorLoad capacity, stiffness, mass flow and orifice sizing for an aerostatic thrust bearing with a simple orifice restrictor. Unlocked from the legacy demo gate; general in its geometry.Aerostatic shallow-pocket thrust bearingLoad capacity, stiffness and flow for an aerostatic shallow-pocket thrust bearing, from the pocket and land pressure profiles. Unlocked from the legacy demo gate; general in its geometry.Aerostatic bearing — grouped inherent orificesDesign pressure ratio and load capacity for an aerostatic thrust bearing fed through grouped inherent orifices.Spiral-groove bearing (axial)Axial load capacity, stiffness, friction torque and power loss for a spiral-groove thrust bearing — a specialist calculation with essentially no free equivalent anywhere.Spiral-groove thrust bearing (design)Operating speed, friction torque and power loss for an axial spiral-groove thrust bearing carrying a given load, from the groove geometry and film thickness.Self-acting spiral-groove journal bearingCompressibility number, dimensionless stiffness and attitude angle for a self-acting (aerodynamic) spiral-groove journal bearing — a specialist gas-bearing calculation with essentially no free equivalent anywhere.Self-acting plain cylindrical journal bearingCompressibility number, dimensionless stiffness and attitude angle for a self-acting (aerodynamic) plain cylindrical journal bearing — a specialist gas-bearing calculation with essentially no free equivalent anywhere.Simple orifice restrictor sizingCross-section area and diameter of a simple orifice restrictor for a gas bearing, from the required flow rate and supply/restrictor/ambient pressures.Hydrostatic circular thrust pad with restrictor choiceLoad capacity, stiffness, flow rate and pump power for a circular hydrostatic thrust pad, with a choice of capillary, orifice or fixed-flow restrictor — after the hydrostatic bearings of the Prins Willem-Alexander locks in Amsterdam.Herringbone thrust bearing (design)Operating speed, friction torque and power loss for a herringbone-profile spiral-groove thrust bearing carrying a given load.Aerostatic thrust bearing, simple orifice restrictor — fixed reference geometry (A)Reference-geometry calculator (Ø40mm outer diameter, 5µm film, β=0.6 pressure ratio — fixed, matching the original) for an aerostatic thrust bearing with a simple orifice restrictor. Vary feed diameter, pressures and discharge coefficient.Aerostatic thrust bearing, simple orifice restrictor with slot-flow check — fixed reference geometry (B)Reference-geometry calculator (Ø40mm outer diameter, 5µm film, β=0.6 — fixed) for an aerostatic thrust bearing with a simple orifice restrictor, including a supply-slot vs. choked-flow area check (A3/A3c).Air bearing, porous surface feed — fixed reference geometryReference-geometry calculator (Ø40mm outer diameter, 5µm film, β=0.6 — fixed) for an aerostatic thrust bearing fed through a porous surface (permeability-coefficient restriction).Air bearing, slot feeding — fixed reference geometryReference-geometry calculator (Ø40mm outer diameter, 5µm film, β=0.6 — fixed) for an aerostatic thrust bearing fed through an annular slot with nr discrete orifices.Thrust-collar air bearing, orifice/slot — fixed reference geometry (A)Reference-geometry calculator (Ø40mm outer diameter, 5µm film, β=0.6 — fixed) for a thrust-collar aerostatic bearing with an outer feed zone and an inner vacuum/exhaust zone.Thrust-collar air bearing, orifice/slot — fixed reference geometry (B)Reference-geometry calculator (Ø40mm outer diameter, 5µm film, β=0.6 — fixed) for a thrust-collar aerostatic bearing fed through a slot of nr discrete orifices, with an inner vacuum/exhaust zone and a supply choked-flow check.Hydrostatic bearing — wedge-film thrust padDimensionless load, stiffness and load-sensitivity for a wedge-film hydrostatic thrust pad, from the film-thickness ratio h1/h0.Hydrostatic bearing — shallow-recess thrust padDimensionless load, stiffness and load-sensitivity for a shallow-recess hydrostatic thrust pad, from the recess-area and film-thickness ratios.Hydrostatic 4-chamber thrust bearingLoad, stiffness, flow and power for a hydrostatic 4-chamber thrust bearing, with a choice of capillary, orifice, or fixed-flow restrictor.Hydrostatic journal bearing, externally pressurizedLoad, stiffness, flow and power for an externally pressurized hydrostatic journal bearing — separated or connected recess elements, with a choice of restrictor.Partially grooved hydrostatic journal bearingLoad and flow for a partially grooved, externally pressurized hydrostatic journal bearing with k grooves, by numerical summation around the circumference.Hydrostatic shallow-pocket liquid thrust bearing — fixed reference geometryReference-geometry calculator (Ø40mm bearing, 5µm film — fixed, matching the original) for a hydrostatic shallow-pocket liquid thrust bearing fed through a small central inlet hole. Vary pocket/inlet diameter, pressures and viscosity.Hydrostatic thrust bearing, central pocket, capillary restrictor — fixed reference geometryReference-geometry calculator (60mm bearing radius — fixed, matching the original) for a circular hydrostatic thrust bearing with a central pocket fed through a capillary restrictor. Vary pocket radius, film thickness, pressure and fluid properties.Orifice-compensated hydrostatic thrust bearing, central pocket — fixed reference geometryReference-geometry calculator (60mm bearing radius — fixed, matching the original) for a circular hydrostatic thrust bearing with a central pocket fed through a sharp-edged orifice. Vary pocket radius, film thickness, pressure and fluid properties.Orifice-compensated hydrostatic thrust bearing, central pocket (lock-gate scale) — fixed reference geometryReference-geometry calculator (650mm bearing diameter, 0.1mm film thickness, 0.7 pressure factor — all fixed, matching the original) for the alternative single-pocket design to the 4-pocket hydrostatic lock-gate bearings of the Prins Willem Alexander Lock in Amsterdam.Hydrostatic journal bearing, multi-recess — fixed reference geometryReference-geometry calculator (60mm shaft diameter, L/D=1, 50 bar supply pressure — all fixed, matching the original) for an externally pressurized journal bearing with 4 or 5 pockets and a choice of capillary, orifice or fixed-flow restrictor.Hydrostatic collar bearing, slot feed through orifices — fixed reference geometryReference-geometry calculator (40mm outer diameter — fixed, matching the original) for a hydrostatic thrust collar bearing fed via a circumferential groove supplied by discrete orifices. Vary groove/inner diameter, film thickness, pressures and fluid properties.Hydrostatic thrust bearing, single center pocket — fixed reference geometryReference-geometry calculator (650mm bearing diameter, 0.1mm film, β=0.7 — fixed, matching the original) for a single-pocket, multi-orifice hydrostatic thrust bearing. Vary pocket diameter, supply pressure and fluid properties.Vacuum-preloaded air bearing, porous ring feed — fixed reference geometryReference-geometry calculator (76mm outer diameter, 5µm film, 0.5MPa supply — fixed, matching the original) for a vacuum-preloaded aerostatic thrust collar bearing fed through a porous ring. Vary the remaining diameters and pressures.Vacuum-preloaded air bearing, simple orifice feed — fixed reference geometryReference-geometry calculator (76mm outer diameter, 5µm film, 0.28MPa supply — fixed, matching the original) for a vacuum-preloaded aerostatic thrust collar bearing fed through discrete simple orifices. Vary the remaining diameters and pressures.Externally pressurized gas bearing — shallow pocket (design chart)Dimensionless pressure ratio, load, stiffness and load-change (at ε=0.5) design formula for an externally pressurized gas bearing with a shallow-pocket (constant-flow) restrictor.Externally pressurized gas bearing — partially grooved surface (design chart)Dimensionless pressure ratio, load, stiffness and load-change (at ε=0.5) design formula for an externally pressurized gas bearing with a partially grooved feed surface.Aerostatic slim air bearing — groove-compensated circular thrust bearingLoad capacity, stiffness, mass flow and volume flow for a circular groove-compensated aerostatic thrust bearing (modeled on the slimairbearings.eu product family).Aerostatic radial bearing — partially porous surfaceLoad, stiffness, restrictor gap and gas flow for a radial (journal) aerostatic bearing fed through a partially porous sleeve surface.Aerostatic radial gas bearing — design and calculationLoad, stiffness, restrictor gap and gas flow for an aerostatic radial (journal) gas bearing, using the porous/groove-feed design correlation for L/D ratios from ~0.25 up.Aerostatic radial bearing — partially grooved surfaceEccentric load capacity and gas mass flow for a partially grooved (symmetric) radial aerostatic bearing, integrated over the groove pattern around the bearing.New Way porous air bearing — flat roundCatalog performance data (load, stiffness, flow, mass) for New Way flat round porous-carbon air bearings, by diameter, at the vendor-fixed 60 psi supply and 5 µm fly height.New Way porous air bearing — bushing (sleeve)Catalog performance data (max load, radial stiffness, flow, mass, dimensions) for New Way porous-carbon air bearing bushings (radial sleeves), by bore diameter, at the vendor-fixed 60 psi supply and 4 µm air gap.Externally pressurized (udv) gas thrust bearing — porous surfaceLoad, stiffness, restrictor gap and gas flow for an externally pressurized aerostatic thrust bearing fed through a porous annular ring.Flow resistance of a compressed-air supply hosePressure drop along a compressed-air supply hose/line for a given flow rate, length and inner diameter — for sizing the air supply feeding an aerostatic bearing.