# Technical Data

## Pressure Drop Calculations

To accurately calculate the pressure loss for filters and strainers in a pipeline, proceed as follows:

• First calculate pressure loss using Cv factor formula at right
• Take the pressure loss figure obtained in (1) and recalculate it using the appropriate correction factor from the following tables.

## Pressure Loss Calculation Using Cv Factor The pressure loss across a strainer or filter can be calculated using the system's flow rate and the Cv factor for that strainer or filter.

For example, a 1 " strainer with a Cv factor of 8 will have a 4 psi pressure loss in a system with a 16 gpm flow rate: (16 ÷ 8) 2 = 4.

## Correction Factors for Mesh-Lined Basket

Water Only

Multiply the pressure drop for perforated baskets by the following.

 Basket Mesh Correction Factor 40 Mesh 1.2 60 Mesh 1.4 80 Mesh 1.6 100 Mesh 1.7 200 Mesh 2.0 325 Mesh 2.5

 Fluids Other Than Water First-Multiply the pressure drop for water shown in charts by the specific gravity of the liquid. Second-Multiply the corrected pressure drop figure by the following correction factors for more viscous liquids. (Water has a viscosity of 30 SSU.) Viscosity  (SSU) Unlined  Perforated  Basket 40 Mesh  Lined  Basket 60 Mesh  Lined  Basket 80 Mesh  Lined  Basket 100 Mesh  Lined  Basket 200 Mesh  Lined  Basket 325 Mesh  Lined  Basket 500 1.6 1.9 2.1 2.4 2.6 3.1 3.6 1000 1.7 2.2 2.4 2.6 2.8 3.3 3.8 2000 1.9 2.4 2.7 2.9 3.2 3.8 4.0 3000 2.0 2.6 2.9 3.2 3.5 4.1 4.3 5000 2.2 3.0 3.5 4.0 4.5 5.3 6.3 10000 2.5 3.5 4.2 5.0 6.0 7.1 8.5