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 22 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 5 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.✓ validatedAerostatic 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.✓ validatedAerostatic bearing — grouped inherent orificesDesign pressure ratio and load capacity for an aerostatic thrust bearing fed through grouped inherent orifices.✓ validatedSpiral-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.✓ validatedSpiral-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.✓ validatedHerringbone thrust bearing (design)Operating speed, friction torque and power loss for a herringbone-profile spiral-groove thrust bearing carrying a given load.✓ validatedAerostatic 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.✓ validatedAerostatic 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).✓ validatedAir 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).✓ validatedAir 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.✓ validatedThrust-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.✓ validatedThrust-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.✓ validatedHydrostatic bearing — wedge-film thrust padDimensionless load, stiffness and load-sensitivity for a wedge-film hydrostatic thrust pad, from the film-thickness ratio h1/h0.✓ validatedHydrostatic 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.✓ validatedHydrostatic 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.✓ validatedHydrostatic 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.✓ validatedPartially grooved hydrostatic journal bearingLoad and flow for a partially grooved, externally pressurized hydrostatic journal bearing with k grooves, by numerical summation around the circumference.✓ validatedExternally 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.✓ validatedExternally 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.✓ validatedAerostatic 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).✓ validatedAerostatic radial bearing — partially porous surfaceLoad, stiffness, restrictor gap and gas flow for a radial (journal) aerostatic bearing fed through a partially porous sleeve surface.✓ validatedAerostatic 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.✓ validatedAerostatic 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.✓ validatedNew 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.✓ validatedNew 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.✓ validatedExternally 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.✓ validatedFlow 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.✓ validated
Gas Bearings — Engineering ABC