1. What is API Gravity?

API Gravity is a measure of how heavy or light a petroleum liquid is compared to water. It was developed by the American Petroleum Institute to standardize measurements of petroleum density.

2. How Does the Calculator Work?

The calculator uses the API Gravity formula:

Where:

• \( API \) — API Gravity in degrees
• \( SG \) — Specific Gravity (dimensionless)

Explanation: The formula converts specific gravity (density relative to water) to the API Gravity scale where higher values indicate lighter liquids.

3. Importance of API Gravity

Details: API Gravity is crucial in the petroleum industry for classifying crude oils, determining product quality, and calculating shipping quantities.

4. Using the Calculator

Tips: Enter specific gravity (SG) value (must be greater than 0). Typical crude oils range from 10° API (heavy) to 50° API (light).

5. Frequently Asked Questions (FAQ)

Q1: What's the relationship between API and density?
A: API is inversely related to density - higher API means lower density (lighter liquid).

Q2: What are typical API values for crude oil?
A: Light crude: >31.1° API, Medium crude: 22.3-31.1° API, Heavy crude: <22.3° API, Extra heavy crude: <10° API.

Q3: How does temperature affect API measurements?
A: API is standardized at 60°F (15.6°C). Measurements at other temperatures must be corrected.

Q4: What's the API of water?
A: Water has an API Gravity of 10° (SG = 1.000).

Q5: Why is API used instead of specific gravity?
A: API provides a more intuitive scale where higher numbers mean lighter products, which is more useful for industry classification.