프로젝트 소개
공학적 투명성과 수리학 계산 표준
배관 수리학, 상수도 분배망, 소방 방재 및 펌프 시스템을 위한 독립 엔지니어링 레퍼런스입니다.
Why we built this platform
A common misconception in piping, irrigation, and field mechanics is that a single pressure gauge reading (PSI or Bar) directly dictates how much water (GPM or L/min) will be delivered. In reality, static pressure is merely potential energy; actual volumetric flow rate depends on internal conduit geometry, pipe surface friction, elevation change, and downstream pressure drop.
Many online calculators treat fluid mechanics as an opaque "black box," omitting the formulas used, assuming arbitrary pipe schedules, or ignoring practical velocity thresholds. PSI to GPM was created to provide engineers, technicians, contractors, and facility managers with transparent calculators displaying explicit formulas, verifiable engineering constants, dual Metric and US Customary units, and practical field limits.
Governing technical standards & references (KO)
Our calculation models and technical documentation cite consensus fluid mechanics references and recognized regional standards:
- 한국산업표준 (KS) 및 국가건설기준 (KCS): KS B 6301 (원심 펌프), KS B 2103 (밸브 유량계수), KCS 31 10 00 (설비공사 일반표준시방서).
- 국가화재안전기준 (NFPC / NFSC): 스프링클러설비의 화재안전기술기준 및 옥외소화전설비 화재안전기준 (NFPA 291 연계 방수압력 측정).
- 크레인 기술자료 410 (Crane TP-410): 밸브, 이음쇠 및 배관 내부의 유체 역학 (달시-바이스바흐 마찰계수 및 밸브 Cv/Kv 산정).
- KS B ISO 5167: 차압 유량계를 이용한 유체 유량 측정 (오리피스, 노즐 및 벤투리관).
- 실제 배관 내경 규격: 배관용 탄소강관 (KS D 3507 SPGF), 배관용 동관 (KS D 5301), 일반 수도용 내충격 PVC관 (KS M 3401) 실측 내경 적용.
Our editorial and calculation methodology
Every tool published on PSI to GPM adheres to four strict engineering principles:
- Explicit Physical Models: We clearly identify whether a calculation utilizes empirical approximations (such as Hazen-Williams for water distribution) or exact rational mechanics (such as Darcy-Weisbach with Colebrook-White friction factors).
- Published Mathematical Constants: Dimensional constants (e.g., 4.52 for Hazen-Williams PSI loss; 29.83 for hydrant discharge coefficients) are shown with their dimensional units and derivations.
- Dimensionally Accurate Internal Diameters: Calculations distinguish nominal pipe sizes from true internal diameters (ID). For example, a 1-inch Schedule 40 PVC pipe has an actual ID of 1.049 inches, yielding substantially different friction losses than nominal dimensions.
- Transparent Limitations & Velocity Safeguards: We highlight erosion thresholds (such as the 5 ft/s limit for domestic copper hot water and 8 ft/s for PVC) and water hammer risks.
Read our full Editorial & Calculation Methodology Policy for in-depth information on our review processes, computational guarantees, and AI usage standards.
Professional engineering disclaimer
All calculators, graphs, tables, and reference materials on PSI to GPM are intended strictly for educational, scoping, field troubleshooting, and preliminary engineering assessment. They do not constitute certified engineering plans, stamped construction drawings, or life-safety submittals. Critical municipal infrastructure, high-hazard fire sprinkler networks, and commercial boiler/pump systems must always be designed, verified, and stamped by a licensed Professional Engineer (PE) and approved by the local Authority Having Jurisdiction (AHJ).
Editorial inquiries, errata & corrections
If you identify a numerical discrepancy, a typo in a derivation, or an updated standard revision, please contact us via our Contact page. We verify all technical feedback against primary engineering references and document all resolved discrepancies publicly in our Calculation Errata & Updates Log.