{"openapi":"3.1.0","info":{"title":"Pipe Insulation API","version":"1.0.0","description":"Pipe-insulation heat-loss maths as an API, computed locally and deterministically — the radial heat loss, thickness and energy-cost numbers a mechanical engineer or energy auditor sizes lagging with. The heat-loss endpoint gives the loss per linear foot through cylindrical insulation, Q/L = 2π·(k/12)·ΔT ÷ ln(r2/r1), where k is the insulation conductivity (BTU·in/hr·ft²·°F, ~0.25 for fibreglass), r1 the pipe radius and r2 the outer radius — a 2-inch line at 300 °F with one inch of fibreglass loses about 43 BTU/hr per foot, and because the relationship is logarithmic, doubling the thickness does not halve the loss. The thickness endpoint inverts it for a target loss: ln(r2/r1) = 2π·(k/12)·ΔT ÷ target, then thickness = r2 − r1, showing the economic-thickness point beyond which more material rarely pays. The annual-cost endpoint turns loss per foot into the yearly heat lost and fuel cost over a run of pipe, the number that justifies the lagging. Everything is computed locally and deterministically, so it is instant and private. Ideal for mechanical-design and energy-audit apps, insulation-contractor and process-piping tools, building-services calculators, and engineering aids. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 compute endpoints. Ignores the outer air film (real loss slightly lower). For flat walls and roofs use a U-value API.","contact":{"name":"PremiumApi","url":"https://www.oanor.com/by/premiumapi"}},"servers":[{"url":"https://api.oanor.com/pipeinsulation-api","description":"oanor gateway"}],"tags":[{"name":"Pipe Insulation"},{"name":"Meta"}],"components":{"securitySchemes":{"oanorKey":{"type":"apiKey","in":"header","name":"x-oanor-key","description":"Get your key at https://www.oanor.com/developer/keys"}}},"security":[{"oanorKey":[]}],"paths":{"/v1/annual-cost":{"get":{"operationId":"get_v1_annual_cost","tags":["Pipe Insulation"],"summary":"Annual loss and fuel cost","description":"","parameters":[{"name":"heat_loss_btu_hr_ft","in":"query","required":true,"description":"Heat loss per foot in BTU/hr","schema":{"type":"string"},"example":"42.9"},{"name":"length_ft","in":"query","required":true,"description":"Pipe run length in feet","schema":{"type":"string"},"example":"100"},{"name":"hours_per_year","in":"query","required":false,"description":"Operating hours/year (default 8760)","schema":{"type":"string"},"example":"8760"},{"name":"price_per_therm","in":"query","required":false,"description":"Gas price per therm (default 1.2)","schema":{"type":"string"},"example":"1.2"},{"name":"boiler_efficiency_pct","in":"query","required":false,"description":"Boiler efficiency % (default 80)","schema":{"type":"string"},"example":"80"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"Annual loss = loss per foot × length × operating hours; fuel = that ÷ 100,000 BTU/therm ÷ the boiler efficiency, times the gas price. A bare or poorly-lagged hot line can leak hundreds of dollars a year, so insulation usually pays back fast — compare against the cost of the lagging to find the payback.","inputs":{"length_ft":100,"hours_per_year":8760,"price_per_therm":1.2,"heat_loss_btu_hr_ft":42.9,"boiler_efficiency_pct":80},"annual_cost":563.71,"annual_therms":469.8,"annual_loss_btu":37580400},"meta":{"timestamp":"2026-06-06T23:53:57.628Z","request_id":"7367d67e-b204-4a96-9dc7-7c0d3f046fa3"},"status":"ok","message":"Annual cost","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/heat-loss":{"get":{"operationId":"get_v1_heat_loss","tags":["Pipe Insulation"],"summary":"Heat loss per foot","description":"","parameters":[{"name":"pipe_od_in","in":"query","required":true,"description":"Pipe outer diameter in inches","schema":{"type":"string"},"example":"2.375"},{"name":"insulation_thickness_in","in":"query","required":true,"description":"Insulation thickness in inches","schema":{"type":"string"},"example":"1"},{"name":"pipe_temp_f","in":"query","required":true,"description":"Pipe temperature °F","schema":{"type":"string"},"example":"300"},{"name":"ambient_temp_f","in":"query","required":true,"description":"Ambient temperature °F","schema":{"type":"string"},"example":"100"},{"name":"k_btu_in","in":"query","required":false,"description":"Insulation k (BTU·in/hr·ft²·°F, default 0.25)","schema":{"type":"string"},"example":"0.25"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"Radial heat loss per foot = 2π·(k/12)·ΔT ÷ ln(r2/r1) — cylindrical conduction, where k is the insulation conductivity (BTU·in/hr·ft²·°F, ~0.25 for fibreglass), r1 the pipe radius and r2 the outer insulation radius. Unlike a flat wall, doubling the thickness does NOT halve the loss because it is logarithmic. Ignores the outer air film, so real loss is a little lower.","inputs":{"k_btu_in":0.25,"pipe_od_in":2.375,"pipe_temp_f":300,"ambient_temp_f":100,"insulation_thickness_in":1},"heat_loss_btu_hr_ft":42.9},"meta":{"timestamp":"2026-06-06T23:53:57.726Z","request_id":"fbd0b911-67c5-48fd-b1e5-94e3b3b19285"},"status":"ok","message":"Heat loss","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/thickness":{"get":{"operationId":"get_v1_thickness","tags":["Pipe Insulation"],"summary":"Thickness for a target loss","description":"","parameters":[{"name":"pipe_od_in","in":"query","required":true,"description":"Pipe outer diameter in inches","schema":{"type":"string"},"example":"2.375"},{"name":"target_loss_btu_hr_ft","in":"query","required":true,"description":"Target loss in BTU/hr per foot","schema":{"type":"string"},"example":"30"},{"name":"pipe_temp_f","in":"query","required":true,"description":"Pipe temperature °F","schema":{"type":"string"},"example":"300"},{"name":"ambient_temp_f","in":"query","required":true,"description":"Ambient temperature °F","schema":{"type":"string"},"example":"100"},{"name":"k_btu_in","in":"query","required":false,"description":"Insulation k (default 0.25)","schema":{"type":"string"},"example":"0.25"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"Thickness for a target loss inverts the cylindrical-conduction law: ln(r2/r1) = 2π·(k/12)·ΔT ÷ target, then thickness = r2 − r1. Because the relationship is logarithmic, chasing a very low loss needs disproportionately thick insulation — there is an economic-thickness sweet spot beyond which more material rarely pays back.","inputs":{"k_btu_in":0.25,"pipe_od_in":2.375,"pipe_temp_f":300,"ambient_temp_f":100,"target_loss_btu_hr_ft":30},"outer_diameter_in":5.68,"required_thickness_in":1.65},"meta":{"timestamp":"2026-06-06T23:53:57.815Z","request_id":"300e1fae-60da-434a-b38a-4996da48a2d4"},"status":"ok","message":"Thickness","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/meta":{"get":{"operationId":"get_v1_meta","tags":["Meta"],"summary":"Spec","description":"","parameters":[],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"notes":"US units. Q/L = 2π·(k/12)·ΔT ÷ ln(r2/r1); k in BTU·in/hr·ft²·°F (~0.25 fibreglass). Ignores outer air film (loss slightly lower). For flat walls/roofs use a U-value API.","service":"pipeinsulation-api","endpoints":{"GET /v1/meta":"This document.","GET /v1/heat-loss":"Heat loss per foot through cylindrical insulation.","GET /v1/thickness":"Insulation thickness for a target heat loss per foot.","GET /v1/annual-cost":"Annual heat loss and fuel cost for a run of pipe."},"description":"Pipe-insulation heat-loss maths: radial conduction per foot, the thickness for a target loss, and the annual heat loss & fuel cost."},"meta":{"timestamp":"2026-06-06T23:53:57.890Z","request_id":"1e7cb045-f53d-4434-8224-678299da5cc9"},"status":"ok","message":"Meta","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}}},"x-oanor-pricing":[{"slug":"free","name":"Free","price_cents_month":0,"monthly_call_quota":480,"rps_limit":2,"hard_limit":true},{"slug":"starter","name":"Starter","price_cents_month":535,"monthly_call_quota":12600,"rps_limit":6,"hard_limit":true},{"slug":"pro","name":"Pro","price_cents_month":1760,"monthly_call_quota":80000,"rps_limit":15,"hard_limit":true},{"slug":"mega","name":"Mega","price_cents_month":5240,"monthly_call_quota":260000,"rps_limit":36,"hard_limit":true}],"x-oanor-marketplace-url":"https://www.oanor.com/api/pipeinsulation-api"}