What Is the ISO 5167 Orifice Plate Gas Mass Flow & Differential Pressure Calculator?
ISO 5167-2 establishes standardized metering equations for differential pressure orifice plates in enclosed closed conduits.
For compressible gas flow, the expansibility factor ε accounts for density changes as gas accelerates through the vena contracta.
This calculator computes diameter ratio β, expansibility factor, mass flow rate in kg/h and standard Nm³/h, and permanent pressure loss.
How Does the ISO 5167 Orifice Plate Gas Mass Flow & Differential Pressure Calculator Work?
The calculation evaluates user-provided measurements using recognized domain equations, converts between measurement units, and adjusts for real-world efficiency factors.
ISO 5167 Orifice Plate Gas Mass Flow & Differential Pressure Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
ISO 5167 differential pressure mass flow equation with gas expansibility factor ε = 1 - (0.351 + 0.256·β⁴ + 0.93·β⁸)·[1 - (p2/p1)^(1/κ)].
How to Use the ISO 5167 Orifice Plate Gas Mass Flow & Differential Pressure Calculator
- Enter your primary measurements in the input fields above.
- Select your preferred units (e.g. metric or imperial) if applicable.
- Review or adjust operational assumptions such as field efficiency.
- Click Calculate to instantly generate the full results breakdown and visual chart.
- Use the Reset button at any time to clear the form and test a new scenario.
Step-by-Step Example Calculation
Gas Pipeline Metering (D = 150mm, d = 90mm, Δp = 250 mbar, p1 = 6 bar)
Input Values:
Understanding Your Result
Your calculated result represents the realistic operational capacity or baseline output under the specified conditions. Comparing theoretical and effective outputs reveals the direct impact of turns, overlap, and practical downtime.
Factors That Affect the Result
Field terrain, operator experience, equipment maintenance, overlap margin, and weather conditions can significantly influence real-world output.
When Should You Use This Calculator?
Use this calculator whenever you need quick, verified estimates for job planning, budgeting, equipment sizing, or project timelines.
Assumptions & Limitations
- For compliance with ISO 5167, the diameter ratio β must lie between 0.10 and 0.75.
- Permanent pressure loss across an orifice plate is typically 50% to 70% of the measured differential pressure.
Frequently Asked Questions
Calculation Accuracy & Reference Note
This calculator implements verified, deterministic mathematical equations based on published standards. Results should be treated as professional engineering estimates; always verify critical operations with local equipment manuals and site inspections.