Continuous Pipeline Filtration
Duplex Strainer Manufacturer
BCST Valve manufactures duplex strainers for pipeline systems that require continuous filtration. Two independent strainer chambers allow flow to be transferred from one basket to the other while the isolated basket is inspected or cleaned.
Our duplex strainer range supports water, oil, fuel, chemical and industrial process applications where an extended shutdown for routine strainer maintenance is undesirable.
- Two independent removable filter baskets
- Manual and actuated changeover options
- Cast and fabricated body configurations
- Perforated, mesh-lined and wedge-wire baskets
- Drain, vent and differential-pressure connections
Continuous Filtration
One basket remains in service while the other is isolated for cleaning.
Large Screen Area
Supports higher flow and improved dirt-holding capacity.
Controlled Changeover
Transfers flow between chambers without a complete process shutdown.
Entretien facile
Top-access baskets simplify inspection, cleaning and replacement.
Product Collection
Duplex Strainer Types
Select the body construction, changeover method and basket design according to the process conditions.
Cast Duplex Strainer
A compact integral-body configuration for general industrial liquid filtration.
- Two removable baskets
- Manual changeover mechanism
- Flanged pipeline connections
Fabricated Duplex Strainer
A welded configuration for larger pipelines, higher flow rates and project-specific arrangements.
- Custom body dimensions
- Large-size capability
- Flexible nozzle orientation
Dual Basket Strainer
Two parallel basket housings connected by isolation and changeover valves.
- Independent chamber isolation
- Parallel filtration arrangement
- Accessible valve maintenance
High-Pressure Duplex Strainer
A reinforced configuration for demanding pipelines with higher design pressure.
- Heavy-duty body construction
- Engineered cover and bolting
- Pressure-class connection options
Actuated Duplex Strainer
Uses an actuator to support remote or automated transfer between filtration chambers.
- Electric or pneumatic options
- Remote changeover capability
- Control-system integration review
Custom Duplex Strainer
A project-engineered solution for special media, screen openings, connections or installation limitations.
- Custom filtration area
- Special material combinations
- Project-specific accessories
Product Comparison
Choose the Appropriate Duplex Strainer
The preferred configuration depends on pipeline pressure, flow rate, available space and changeover requirements.
| Duplex Strainer Type | Body Construction | Changeover Method | Configuration Benefit | Typical Application |
|---|---|---|---|---|
| Cast Duplex Strainer | Integral cast body | Manuel | Compact arrangement | General industrial liquids |
| Fabricated Duplex Strainer | Welded construction | Manual or actuated | Flexible size and layout | Large-flow process systems |
| Dual Basket Strainer | Separate chambers | Isolation valves | Independent chamber maintenance | Continuous-process pipelines |
| High-Pressure Duplex Strainer | Heavy-duty construction | Manual or actuated | Higher-pressure capability | Oil, fuel and process service |
| Actuated Duplex Strainer | Cast or fabricated | Électrique ou pneumatique | Remote changeover | Automated process systems |
| Custom Duplex Strainer | Project engineered | Project dependent | Application-specific design | Special process requirements |
Operating Principle
How a Duplex Strainer Works
A duplex strainer contains two filtration chambers. During normal operation, flow passes through one basket while the second chamber remains ready for service.
- Process fluid enters the active filtration chamber.
- Solid particles collect inside the removable basket.
- Differential pressure increases as debris accumulates.
- Flow is transferred gradually to the clean chamber.
- The contaminated chamber is isolated and depressurized.
- The basket is removed, cleaned and returned to standby.
Full Flow Capacity
Each chamber must support the required operating flow.
Safe Changeover
Flow transfer should avoid interruption and damaging pressure surges.
Reliable Isolation
The offline chamber must be isolated before opening its cover.
Basket Accessibility
Adequate clearance is required for safe basket removal.
Technical Options
Duplex Strainer Configuration Guide
Available configurations depend on the selected series and project conditions. Confirm the complete specification before ordering.
| Paramètres | Typical Options | Information Required |
|---|---|---|
| Body Construction | Cast or fabricated | Size, pressure and project specification |
| Pipeline Connection | Flanged, threaded or welded | Piping standard and pressure class |
| Changeover | Manual, electric or pneumatic | Operating and control requirements |
| Cover | Bolted, hinged or quick opening | Pressure and maintenance frequency |
| Basket Construction | Perforated, mesh lined or wedge wire | Particle size and mechanical strength |
| Drain and Vent | Plugged, flanged or valve connections | Isolation and maintenance procedure |
| Monitoring | Pressure gauge or differential-pressure connections | Maintenance and control strategy |
| Accessoires | Support legs, lifting devices and actuators | Installation and operating requirements |
Sélection des paniers
Screen Opening and Filtration Area
Each basket should provide the required particle retention, mechanical strength and filtration area at the design flow rate.
Basket Construction Options
- Perforated plate for coarse filtration
- Perforated support with woven wire mesh
- Wedge-wire basket for selected applications
- Single-layer or multi-layer construction
- Reinforced basket for higher differential pressure
Selection Considerations
- Smallest damaging particle size
- Expected particle concentration
- Required flow rate and fluid viscosity
- Allowable clean and dirty pressure drop
- Required cleaning and replacement interval
| Basket Type | Filtration Characteristic | Relative Strength | Utilisation typique |
|---|---|---|---|
| Perforated Basket | Coarse particle removal | Haut | Pipeline and pump protection |
| Mesh-Lined Basket | Medium or fine filtration | Supported | Meters, valves and process equipment |
| Wedge-Wire Basket | Uniform slot opening | Haut | Water and selected process applications |
| Reinforced Basket | Application-specific filtration | Very high | Higher differential-pressure conditions |
Changeover Methods
Manual and Actuated Flow Transfer
The changeover arrangement should maintain process flow while providing reliable isolation of the chamber being serviced.
| Changeover Type | Fonctionnement | Control Requirement | Typical Selection Reason |
|---|---|---|---|
| Manual Lever | Local operator transfer | No external power | Simple and economical operation |
| Manual Valve Arrangement | Sequential valve operation | Defined operating procedure | Independent chamber isolation |
| Actionneur électrique | Remote or automated transfer | Electrical supply and control signal | Central control-system integration |
| Actionneur pneumatique | Remote or automated transfer | Instrument air and control signal | Process automation applications |
Matériaux
Material Options for Different Media
Body, basket, gasket, valve and bolting materials should be selected together according to the fluid, pressure, temperature and corrosion conditions.
| Composant | Typical Material Options |
|---|---|
| Corps | Cast iron, ductile iron, carbon steel, SS304 or SS316 |
| Fabricated Housing | Carbon steel, SS304, SS304L, SS316 or SS316L |
| Filter Basket | SS304, SS304L, SS316 or SS316L |
| Changeover Components | Carbon steel, stainless steel or project-specified alloy |
| Cover Gasket | Graphite, PTFE or application-specific material |
Selection Checklist
Information Required for Duplex Strainer Selection
Complete operating data allows the manufacturer to review flow capacity, basket area, screen opening and changeover requirements.
Process Data
- Fluid name and composition
- Design pressure and temperature
- Operating pressure and temperature
- Normal and maximum flow rates
- Fluid density and viscosity
Filtration Data
- Required screen opening
- Particle type and concentration
- Perte de charge admissible
- Required filtration area
- Basket and mesh material
System Requirements
- Pipeline size and connection standard
- Manual or actuated changeover
- Available installation space
- Drain, vent and monitoring requirements
- Inspection and documentation scope
Applications
Duplex Strainer Applications
Duplex strainers protect critical equipment in processes where filtration must continue during routine basket maintenance.
Pétrole et gaz
Continuous filtration for fuel, lubricating oil and transfer systems.
Traitement chimique
Material-compatible filtration for chemicals, solvents and process liquids.
Production d'électricité
Continuous protection for cooling, fuel and auxiliary systems.
Marine & Utilities
Filtration for seawater, cooling water, lubrication and utility pipelines.
Manufacturer Quality Control
Inspection Before Delivery
The inspection scope depends on the selected duplex strainer construction and agreed project requirements.
- Review the approved datasheet and product drawing.
- Verify body, basket, gasket and bolting materials.
- Inspect dimensions, nozzle orientation and connections.
- Check basket opening, construction and fit.
- Verify changeover and chamber-isolation functions.
- Perform pressure and leakage testing where applicable.
Installation & Maintenance
Maintain Continuous Filtration Safely
A controlled changeover procedure and reliable chamber isolation are essential before opening either basket cover.
Installation Guidelines
- Match the body arrow to the pipeline flow direction.
- Provide sufficient clearance above both covers.
- Support connected piping and the strainer body.
- Install vents and drains in accessible positions.
- Provide differential-pressure monitoring where required.
- Confirm changeover operation before commissioning.
Maintenance Guidelines
- Transfer flow fully to the clean chamber.
- Isolate, depressurize and drain the dirty chamber.
- Confirm zero pressure before opening the cover.
- Clean and inspect the removed basket.
- Replace damaged gaskets before reassembly.
- Return the cleaned chamber to standby service.
Send Us Your Duplex Strainer Data
Provide the pipe size, flow rate, pressure, temperature, medium, screen opening and changeover requirements. BCST Valve will review the information and recommend a suitable duplex strainer.
Questions fréquemment posées
Duplex Strainer FAQ
Answers to common questions from engineers, operators and procurement teams.
What is a duplex strainer?
A duplex strainer contains two filter chambers. Flow can be transferred between them so one basket can be cleaned while the other remains in service.
Why use a duplex instead of a simplex strainer?
A duplex strainer is preferred when the process cannot be shut down for routine basket cleaning. A simplex strainer normally requires pipeline isolation.
Does flow stop during changeover?
A correctly operated duplex strainer is designed to maintain process flow during transfer. The approved operating sequence must be followed.
Can both chambers operate at the same time?
This depends on the design. Most duplex strainers use one chamber at a time, while some dual-basket arrangements can support parallel operation.
How is the basket opening selected?
Select an opening small enough to protect downstream equipment while maintaining acceptable flow, basket strength and cleaning intervals.
How do I know when to change chambers?
Inlet and outlet pressure readings can indicate basket blockage. Changeover is normally performed when differential pressure reaches the site-defined limit.
Can the changeover be automated?
Selected configurations can use electric or pneumatic actuators. The control logic, fail position, power supply and feedback requirements must be confirmed.
Can the baskets be customized?
Project-specific basket openings, materials, reinforcement and filtration areas can be reviewed against the process conditions.
What materials are available?
Common options include cast iron, ductile iron, carbon steel, SS304 and SS316 bodies with stainless steel filter baskets.
What information is required for a quotation?
Provide the pipe size, flow rate, pressure, temperature, medium, screen opening, connection standard, materials and changeover requirements.
Need Help Selecting a Duplex Strainer?
Send your process and filtration data to BCST Valve for technical selection and quotation support.
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