A strainer is an essential component of any piping installation. It removes impurities from the pipeline and protects pumps, meters, valves and other mechanical equipment from damage. Luna Flow Control supplies strainers in a range of materials, nominal diameters, pressure ratings and connection types, so they can deliver long-term performance in installations of many different designs.
What Is a Strainer?
A strainer is a piece of pipeline equipment that filters out and retains foreign matter carried in the line. Dirt can cause blockages in pipelines and contamination in production processes; strainers prevent both. Their main function is to protect the other equipment in the line, so that pumps, meters, control valves and regulators can operate without interruption and the process medium stays clean.
Working Principle
The fluid passes through a screen inside the strainer body, which holds back solid particles and removes them from the flow. The screen can be a perforated plate or a wire mesh. Although the principle is very simple, it is vital for the smooth operation of downstream equipment and saves the costs associated with breakdowns and line stoppages.
Types of Strainers
- Stainless steel strainers – long service life and resistance to oxidation and wear; suitable for all types of fluids.
- Flanged strainers – practical units that separate foreign matter from different fluids in various pipelines.
- Y-type strainers – protect process equipment at temperatures from -200 °C to +700 °C in lines carrying liquids, gases, steam, natural gas, hot water, LPG and fuel oil; they require little maintenance.
- T-type strainers – separate dirt, residues and other particles; available in cast iron, ductile iron, stainless steel and bronze, with flanged, welded or threaded ends.
- Mud (sludge) strainers – filter and separate sludge from the fluid to protect pumps, valves and meters.
Size Ranges
| Body material | Pressure rating | Size range |
|---|---|---|
| Cast iron | PN 16 | DN 15 – 300 |
| Stainless steel | PN 16 – 40 | DN 15 – 250 |
| Forged steel | PN 16 – 40 | DN 15 – 250 |
| Forged steel | PN 63 – 100 | DN 15 – 200 |
| Forged steel | PN 160 | DN 15 – 200 |
Application Areas
Strainers protect meters, valves, pumps, steam traps, regulators and other equipment. As a cost-effective and practical solution, they are used in:
- Chemical and petrochemical industries
- Oil industry and refineries
- Power generation
- Marine applications
- Heating and cooling lines and central heating
- Food processing plants
- Iron and steel works
- Paper mills
Advantages
- Prevents damage and blockages caused by foreign particles
- Reduces repair costs and unplanned downtime
- Simple design with low maintenance
- Wide temperature range from -200 °C to +700 °C
Selection and Maintenance Tips
Select the body material, connection type and pressure rating according to the medium and operating conditions, and choose the screen type according to the particle size to be retained. Inspect and clean the screen regularly, as a clogged screen increases pressure drop and reduces flow.
