#mechanical

Roller-chain power-transmission maths as an API, computed locally and deterministically. The ratio endpoint computes a chain drive's speed ratio (driven ÷ driver teeth), the output rpm and torque multiplier, the chain (line) velocity v = N·p·rpm/60 and the pitch diameter of each sprocket, PD = p/sin(π/N), from the driver and driven tooth counts, the input speed and the chain pitch. The length endpoint computes the chain length in pitches and then rounds it up to an even number of links — links must come in pairs — using L = 2C/p + (N1+N2)/2 + ((N2−N1)/2π)²·p/C from the tooth counts, the centre distance and the pitch. The center-distance endpoint inverts that relation to give the exact centre distance for a chosen even link count, C = (p/8)·[(2L−N1−N2) + √((2L−N1−N2)² − 8·((N2−N1)/2π)²)]. Tooth counts are integers, pitch and centre distance in metres (the default pitch 0.0127 m is ANSI 40, ½ inch) and speeds in rpm. Everything is computed locally and deterministically, so it is instant and private. Ideal for mechanical, machine-design, conveyor, motorcycle and industrial-equipment app developers, sprocket-sizing and chain-selection tools, and engineering education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is industrial roller-chain drives; for bicycle gearing use a bike-gear API and for belt or gear ratios a gear-ratio API.

api.oanor.com/chain-api

Thin-walled pressure-vessel engineering maths as an API, computed locally and deterministically. The thin-wall endpoint computes the wall stresses in a cylindrical or spherical vessel under internal pressure: for a cylinder the hoop (circumferential) stress σ_h = p·r/t and the longitudinal stress σ_l = p·r/(2t), which is half the hoop — so cylinders tend to split along their length — together with the von Mises equivalent stress, and for a sphere the single biaxial stress σ = p·r/(2t); it also reports the radius-to-thickness ratio and whether the thin-wall assumption (r/t ≳ 10) holds. The thickness endpoint computes the wall thickness required to keep the hoop stress within an allowable value, t = p·r/(σ_allow·E), with a weld-joint efficiency factor. The burst endpoint computes the theoretical burst pressure of a pipe from Barlow's formula, p = 2·S·t/OD, using the ultimate tensile strength. Pressures and stresses are in pascals (megapascals also returned) and dimensions in metres. Everything is computed locally and deterministically, so it is instant and private. Ideal for mechanical, chemical-plant, piping, boiler and tank-design app developers, ASME-style sizing and safety tools, and engineering education; for code work consult the applicable standards. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is thin-walled vessel stress; for general stress transformation use a Mohr-circle API and for fatigue a fatigue API.

api.oanor.com/pressurevessel-api

Mechanical-fatigue engineering maths as an API, computed locally and deterministically. The stress-cycle endpoint decomposes a cyclic load given by its maximum and minimum stress into the alternating stress σa = (σmax − σmin)/2, the mean stress σm = (σmax + σmin)/2, the stress range and the stress ratio R = σmin/σmax, and names the loading (fully reversed at R = −1, repeated at R = 0). The criteria endpoint computes the infinite-life safety factor against fatigue using the three classic mean-stress theories — Goodman (1/n = σa/Se + σm/Sut, standard and safe), Soderberg (uses the yield strength, conservative) and Gerber (a parabola, least conservative) — from the alternating and mean stress, the endurance limit Se, the ultimate strength Sut and an optional yield strength. The endurance-limit endpoint estimates the corrected endurance limit Se = ka·kb·kc·kd·ke·Se' from the ultimate strength, with Se' = 0.5·Sut for steel and the Marin modifying factors for surface finish, size, load type, temperature and reliability. Stresses and strengths use any one consistent unit (MPa is typical). Everything is computed locally and deterministically, so it is instant and private. Ideal for mechanical, structural, automotive and aerospace-design app developers, durability and safety-factor tools, and engineering education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is fatigue and endurance; for static stress transformation use a Mohr-circle API and for column buckling a buckling API.

api.oanor.com/fatigue-api

Rotational and shaft-power maths as an API, computed locally and deterministically. The power endpoint relates mechanical power, torque and rotational speed — give any two of the power, the torque in newton-metres and the speed in rpm and it returns the third using P = T·ω with ω = 2πN/60, reporting the angular velocity and the power in watts, kilowatts, mechanical horsepower and metric horsepower (PS). The angular endpoint converts a rotational speed freely between rpm, radians per second, degrees per second and hertz (revolutions per second), and — given a radius — the tangential speed and centripetal acceleration at the rim. The units endpoint converts power across watts, kilowatts, mechanical horsepower (745.7 W), metric horsepower or PS (735.5 W), foot-pounds per second and BTU per hour. Everything is computed locally and deterministically, so it is instant and private. Ideal for automotive, motor, drivetrain, robotics and machinery app developers, engine and gearbox tools, and mechanical-engineering education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is mechanical shaft power; for bolt tightening torque use a torque API and for electrical power factor a power-factor API.

api.oanor.com/shaftpower-api

Belt-drive and pulley maths as an API, computed locally and deterministically. The belt endpoint computes the length of an open V-belt or flat belt from the two pulley diameters and the centre distance with L = 2C + (π/2)(D1+D2) + (D1−D2)²/(4C), and returns the belt length plus the wrap (contact) angle on each pulley; pass a driver rpm and it also gives the belt surface speed. The ratio endpoint computes the speed ratio of a pulley pair (driven ÷ driver diameter, since N1·D1 = N2·D2): give a driver or driven rpm and it returns the other, the torque ratio and the belt speed. The centers endpoint reverses the length equation to find the centre distance for a target belt length, solving the equation numerically. Diameters and distances accept millimetres, centimetres, metres, inches or feet, and lengths are reported in several units. Everything is computed locally and deterministically, so it is instant and private. Ideal for machine and drivetrain design tools, maintenance and MRO apps, maker and CNC projects, and mechanical-engineering calculators. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is belt-and-pulley power transmission; for bicycle gear ratios and development use a bike-gear API and for bolt tightening torque use a torque API.

api.oanor.com/beltdrive-api

Bolt and fastener torque maths as an API, using the standard short-form relation T = K · D · F — torque equals the nut factor times the bolt diameter times the clamp load (preload). The torque endpoint computes the tightening torque, in newton-metres, foot-pounds, inch-pounds and kilogram-force metres, from the bolt diameter, the target clamp load and a nut factor — given directly or chosen from a condition preset (dry, lubricated, zinc-plated, galvanized, waxed and more). The preload endpoint solves the inverse: the clamp load a given torque produces on a bolt of a given diameter and friction. The convert endpoint converts a torque value between newton-metres, foot-pounds, inch-pounds and kilogram-force metres. Everything is computed locally and deterministically, so it is instant and private. The K·D·F short form is an estimate that depends heavily on friction — it is engineering guidance only, so always follow the manufacturer's torque specification. Ideal for mechanical, automotive and aerospace tools, maker and assembly apps, maintenance and field-service software, and engineering calculators. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is fastener torque; for wire gauge and resistance use a wire-gauge API and for Ohm's law use an electronics API.

api.oanor.com/torque-api