processconvert
Concept explainers

Engineering Guides

Concise guides explaining the engineering concepts behind the calculators and unit conversions on ProcessConvert. Each guide covers the definition, formula, worked example, common mistakes, and links to the relevant calculator.

These guides complement the interactive calculators with theory and context. More guides are planned for future releases.

Available guides
20 guides
Pumps & Rotating Equipment

What Is Pump Head?

Pump head is energy per unit weight of fluid, expressed as an equivalent height of liquid column. Learn why it matters for pump selection and how it relates to pressure.

Calculator: Head to Pressure Calculator, Pump Hydraulic Power Calculator
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Fluid Mechanics

Pressure vs Head Explained

Pressure is force per area; head is equivalent fluid column height. Learn how density connects them and when to use each.

Calculator: Head to Pressure Calculator
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Fluid Mechanics

Mass Flow vs Volumetric Flow

Volumetric flow measures volume per time; mass flow measures mass per time. Learn the density relationship and when each matters.

Calculator: Mass Flow / Volumetric Flow Calculator, Pipe Velocity Calculator
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Instrumentation

How 4–20 mA Scaling Works

The 4–20 mA current loop is the dominant analogue signal standard in process instrumentation. Learn the scaling formula and how to convert between signal and process value.

Calculator: 4–20 mA Scaling Calculator
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Heat Transfer

Heat Duty Explained

Heat duty is the rate of heat transfer needed to change a fluid temperature. Learn the sensible heat formula, required inputs, and common mistakes.

Calculator: Heat Duty Calculator
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Heat Transfer

What Is Specific Heat Capacity?

Specific heat capacity (Cp) is the energy required per unit mass per degree of temperature change. Learn why it matters in heat duty calculations and how units relate.

Calculator: Heat Duty Calculator
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Heat Transfer

Sensible Heat vs Latent Heat

Sensible heat changes temperature; latent heat changes phase. Learn how they differ, why the heat duty calculator covers sensible heat only, and what latent heat requires.

Calculator: Heat Duty Calculator
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Process Design

Residence Time Explained

Residence time is the average time material spends inside a vessel, equal to volume divided by volumetric flow rate. Learn the formula, units, and common mistakes.

Calculator: Residence Time Calculator, Tank Volume Calculator
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Process Design

Tank Volume Explained

Tank volume is the internal geometric capacity of a vessel. Learn formulas for rectangular tanks, vertical cylinders, and horizontal cylinders, and when each applies.

Calculator: Tank Volume Calculator, Residence Time Calculator
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Fluid Mechanics

Reynolds Number Explained

The Reynolds number is a dimensionless ratio that indicates whether flow is laminar, transitional, or turbulent. Learn the formula, flow regime thresholds, and common mistakes.

Calculator: Reynolds Number Calculator, Pipe Velocity Calculator
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Electrical & Instrumentation

Ohm's Law Explained

Ohm's Law relates voltage, current, and resistance in a DC or purely resistive circuit: V = IR. Learn the three forms of the equation, common units, and when to use each.

Calculator: Ohm's Law Calculator, Electrical Power Calculator
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Electrical & Instrumentation

Electrical Power Explained

Electrical power is the rate of energy transfer in a circuit: P = VI. Learn the three equivalent DC power formulas, common units (W, kW, hp), and limitations.

Calculator: Electrical Power Calculator, Ohm's Law Calculator
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Electrical & Instrumentation

Voltage Drop Explained

Voltage drop is the loss of voltage across a conductor as current flows through its resistance. Learn the formula, percent drop, and the difference between calculation and cable sizing.

Calculator: Voltage Drop Calculator, Ohm's Law Calculator
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Electrical & Instrumentation

RTD Temperature Explained

A resistance temperature detector (RTD) measures temperature via the change in resistance of a platinum element. Learn the Pt100/Pt1000 linear approximation, default alpha, and limitations.

Calculator: RTD Temperature Calculator
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Instrumentation

Percent Span Explained

Percent span expresses a process value as a percentage of the instrument range (LRV to URV). Learn the formula, the difference from 4-20 mA scaling, and common mistakes.

Calculator: Sensor Percent Span Calculator, 4-20 mA Scaling Calculator
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Process Utilities

Dilution Explained

Dilution reduces concentration by adding solvent or increasing final volume. Learn the C1V1 = C2V2 formula, how to calculate added solvent volume, and common mistakes.

Calculator: Dilution Calculator, Concentration Calculator
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Process Utilities

Concentration Explained

Concentration is the amount of solute per amount of solution. Learn the difference between mass concentration and percent by mass, with worked examples and common mistakes.

Calculator: Concentration Calculator, Dilution Calculator
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Process Utilities

Percent Solids Explained

Percent solids is the mass fraction of solid material in a slurry. Learn the formulas for solids mass flow, liquid mass flow, and slurry mass flow, with a worked example.

Calculator: Slurry Solids Calculator, Mass Flow / Volumetric Flow Calculator
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Process Design

Tank Turnover Explained

Tank turnover is how many tank volumes pass through a vessel over time. Learn the turnover rate, turnover time, and how tank turnover differs from residence time.

Calculator: Tank Turnover Calculator, Residence Time Calculator, Tank Volume Calculator
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Pumps & Rotating Equipment

Pump Affinity Laws Explained

The pump affinity laws relate flow, head, and power to pump speed for the same pump and impeller. Learn the three scaling formulas, a worked example, and key limitations.

Calculator: Pump Affinity Laws Calculator, Pump Hydraulic Power Calculator, Head to Pressure Calculator
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Scope

These guides cover the engineering theory behind pump head, pressure/head conversion, mass and volumetric flow, 4–20 mA instrumentation scaling, and sensible heat duty. Each guide includes formulas, worked examples, and links to the relevant interactive calculator. Additional guides are planned for future releases.