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API Gravity Calculator

API Gravity Formula:

\[ °API = \frac{141.5}{SG} - 131.5 \]

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1. What is API Gravity?

Definition: API gravity is a measure of how heavy or light a petroleum liquid is compared to water.

Purpose: It's used by the petroleum industry to classify crude oil and petroleum products.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ °API = \frac{141.5}{SG} - 131.5 \]

Where:

Explanation: The formula compares the density of the petroleum liquid to water (SG = 1.0).

3. Importance of API Gravity

Details: API gravity is important for:

4. Using the Calculator

Tips: Enter the specific gravity of your petroleum liquid (must be > 0). The specific gravity is the ratio of the density of the liquid to the density of water.

5. Frequently Asked Questions (FAQ)

Q1: What does API stand for?
A: API stands for American Petroleum Institute, which developed this measurement scale.

Q2: What's considered "light" crude oil?
A: Crude oil with API gravity > 31.1° is considered light, between 22.3° and 31.1° is medium, and < 22.3° is heavy.

Q3: How is specific gravity measured?
A: Specific gravity is typically measured using a hydrometer or digital density meter at standard conditions (60°F/15.6°C).

Q4: What's the API gravity of water?
A: Water has an API gravity of 10° (when SG = 1.0).

Q5: Can API gravity be negative?
A: Yes, for very dense materials (SG > 1.076), API gravity can be negative.

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