Convert between different mud weight units including ppg, specific gravity, kg/m³, and g/cm³. Essential for drilling operations and fluid management.
Mud weight is the density of the drilling fluid used to control formation pressure and keep the wellbore stable. It is commonly expressed in pounds per gallon (ppg) or specific gravity (SG). Converting between ppg, SG, and other density units is a routine task in daily drilling operations.
The relationship between mud weight in ppg and specific gravity is linear. The basic formula is:
SG = MW_ppg / 8.345
Example: A 12.5 ppg mud has:SG = 12.5 / 8.345 ≈ 1.50
To convert SG back to ppg, use the inverse relationship:
MW_ppg = SG × 8.345
Example: A fluid with SG = 1.6 has:MW_ppg = 1.6 × 8.345 ≈ 13.35 ppg
Quick reference values for common drilling fluid densities:
| Specific Gravity (SG) | Mud Weight (ppg) |
|---|---|
| 1.20 | 10.01 |
| 1.30 | 10.85 |
| 1.40 | 11.68 |
| 1.50 | 12.52 |
| 1.60 | 13.35 |
| 1.70 | 14.19 |
Fresh water at standard conditions has SG = 1.0 and a mud weight of about 8.345 ppg.
SG is unitless and widely used in lab reports, datasheets, and international documents. It makes it easy to compare fluid densities without depending on local unit systems.
Yes. The conversion is a simple constant ratio based on the density of water. As long as the reference is water at standard conditions, the relationship is linear.
All conversions use ppg as the base unit
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