Hygienic Flow Protection

Non-Return Valves Hygienic Check Valves for One-Way Flow & Backflow Prevention

Non-Return Valves, also known as Check Valves or One-Way Valves, are automatic hygienic valves designed to allow product flow in one direction while preventing reverse flow inside sanitary process systems. Depending on the valve design, closing force may be generated by a spring-loaded mechanism or a magnetic operating principle.

Backflow Prevention Automatic One-Way Flow Spring Operated Magnetic Operated CIP Compatible Food, Dairy & Beverage
View Valve Families Working Principle OEM Part Numbers
Hygienic Check Valve — Operating Principle
Automatic Process Protection
Reverse flow blocked
Opens above Cracking Pressure
Forward Product Flow
Automatic Reverse-Flow Protection

Hygienic One-Way Flow Protection

In hygienic process lines, a Non-Return Valve opens automatically when upstream pressure exceeds the valve's opening force, commonly referred to as Cracking Pressure. When forward pressure decreases or reverse pressure develops, the internal plug or disc returns to the seat and closes the flow path. This automatic response helps protect pumps, heat exchangers, pasteurizers, filling systems, dosing equipment and sensitive instruments from reverse flow, contamination and hydraulic disturbances. Hygienic Check Valves are widely used throughout dairy, beverage, food, pharmaceutical and sanitary processing installations.

Forward Flow Allows controlled product movement in the intended direction.
Backflow Protection Automatically blocks reverse flow and protects connected equipment.
Self-Acting Operation No external pneumatic actuator is required for basic operation.
Hygienic Design Suitable for sanitary piping, product transfer and CIP duties.
Operating Principle

How a Hygienic Non-Return Valve Works

A Non-Return Valve responds automatically to the pressure difference across the valve. It opens for forward flow and closes when pressure falls or when reverse pressure develops, protecting the process line without an external actuator.

01

Normally Closed Position

With no sufficient inlet pressure, the spring or magnetic closing force keeps the internal plug firmly against the valve seat. The flow path remains closed and reverse migration of product is prevented.

Closed at Rest
02

Forward Flow Opens the Valve

When upstream pressure becomes greater than the closing force, the plug lifts from the seat. This minimum opening pressure is commonly called the Cracking Pressure.

Pressure-Activated Opening
03

Reverse Flow Closes the Valve

If forward pressure decreases or flow reverses, the closing mechanism returns the plug to the seat. Reverse pressure then reinforces the seal and helps block unwanted backflow.

Automatic Backflow Protection

Spring-Operated Check Valve

In a spring-operated design, a mechanical spring applies a defined closing force to the valve plug. Forward product pressure must overcome this force before the valve can open.

  • Predictable mechanical closing action and automatic operation.
  • Suitable for hygienic product transfer and process protection duties.
  • Typical internal service items include the spring, plug and seals.
  • Valve orientation and pressure conditions must be considered during selection.

Magnetic-Operated Check Valve

In a magnetic-operated design, magnetic force controls the closing movement of the internal valve element. This arrangement is used in specialized hygienic applications requiring a compact and clean design.

  • Automatic one-way operation without an external actuator.
  • Designed for high-hygiene process applications.
  • Closing performance depends on magnetic force and process pressure.
  • Exact model, size, material and connection standard must be verified.

Main Internal Components

Although construction varies by model, hygienic Non-Return Valves normally contain a compact set of internal components that create the opening, closing and sealing functions.

Valve Body Hygienic stainless-steel pressure boundary with process connections matched to the installed piping standard.
Plug or Disc Movable closing element that lifts during forward flow and returns against the seat when the valve closes.
Valve Seat & Seal Creates the shut-off interface and prevents reverse leakage when the internal element is in the closed position.
Closing Mechanism Mechanical spring or magnetic force that returns the plug to the closed position when forward pressure is insufficient.
Guide & Stem Maintains correct alignment and smooth movement of the internal closing element during repeated opening cycles.
Clamp Assembly Used on serviceable designs to connect body sections and allow controlled access to internal components.
Process Connections Welded or other hygienic connection executions selected according to pipe size, standard and plant requirements.
Product-Wetted Surfaces Internal surfaces exposed to product and cleaning media, requiring hygienic geometry and suitable material compatibility.

Important Engineering Terminology

Technical Term Meaning Why It Matters Selection Consideration
Cracking Pressure Minimum upstream differential pressure required to begin opening the valve. Determines when forward flow can start through the valve. Must be compatible with available process pressure and pump duty.
Back Pressure Pressure acting from the downstream side toward the inlet side. Helps keep the valve closed during a reverse-flow condition. Maximum reverse pressure must remain within the valve rating.
Pressure Differential Difference between upstream and downstream process pressure. Controls whether the valve opens, remains open or closes. Evaluate normal operation, start-up and transient conditions.
Flow Direction Intended direction in which product is permitted to pass. Incorrect installation orientation can prevent proper operation. Confirm the valve flow arrow before installation.
Reverse Leakage Unwanted leakage through the valve while reverse pressure is applied. Can affect product separation, hygiene and equipment protection. Seat condition, seal material and pressure must be evaluated.
Self-Acting Valve Valve that operates automatically from process pressure without a pneumatic or electric actuator. Simplifies installation and reduces external control requirements. Correct pressure conditions are essential for reliable operation.
Product-Wetted Parts Components and surfaces that come into direct contact with product. Material, surface condition and cleanability affect hygienic safety. Confirm stainless-steel grade, seal material and approval needs.
Installation Orientation Physical position of the valve in vertical or horizontal piping. Gravity and internal construction may influence opening behaviour. Match the valve model to the actual piping arrangement.

Cracking Pressure is not the same as operating pressure

Cracking Pressure describes the differential pressure at which the valve first begins to open. The valve's allowable operating pressure is a separate mechanical rating. Both values must be considered when selecting a hygienic Check Valve for a process line.

Spring-Operated Model

LKC-2 Hygienic Non-Return Valve

The LKC-2 is a compact spring-operated Check Valve designed to permit one-way flow and prevent reverse movement of product in hygienic process piping. Its serviceable construction combines a clamp-assembled body, hygienic seal ring and welded process connections.

LKC-2 — Spring-Operated Check Valve
Intended
Flow Direction
Spring-Loaded Closing
Clamp-Assembled Body
ISO / DIN Weld Ends
MODEL FAMILY: LKC-2

Compact Automatic Backflow Protection

The LKC-2 uses a mechanical spring to hold the internal valve element against its seat. When inlet pressure exceeds the spring force, the valve opens and allows forward flow. When pressure decreases or a reverse-pressure condition occurs, the spring returns the closing element to the seat and blocks backflow.

Spring Operated Mechanical closing force provides automatic operation.
Clamp Assembly Body sections are assembled using a clamp ring.
Hygienic Seal Ring Sealed construction supports sanitary process service.
Welding Ends Available for ISO or DIN piping connections.
Self-Acting No external pneumatic actuator is required.
Reverse-Flow Protection Helps protect connected process equipment and product flow.
The exact valve size, material execution, connection standard, seal material and OEM Part Number must be confirmed before quotation or replacement.

Construction & Design Characteristics

LKC-2 combines a compact hygienic body with a serviceable internal assembly and automatic spring-assisted closing action.

Hygienic Valve Body Stainless-steel body designed for product-contact service in sanitary process systems.
Mechanical Spring Provides closing force and returns the internal element to the seat when forward pressure is insufficient.
Movable Plug Lifts under forward differential pressure and closes automatically during reverse-flow conditions.
Seal Ring Creates the hygienic body seal and must match the required elastomer execution and process conditions.
Clamp Ring Holds the main body sections together and supports controlled access during inspection and servicing.
Welded Connections Welding ends are selected to match ISO or DIN piping dimensions and the site's hygienic installation standard.

LKC-2 Operating Sequence

The complete opening and closing cycle is driven by the pressure difference across the valve and the opposing force of the internal spring.

01

Closed at Rest

Without sufficient inlet pressure, the spring keeps the plug seated and the valve remains closed.

02

Forward Pressure Rises

Inlet differential pressure increases until it overcomes the spring force and begins lifting the plug.

03

Valve Opens

Product passes through the valve in the permitted flow direction while sufficient forward pressure is maintained.

04

Pressure Falls

When forward pressure decreases, the spring pushes the internal plug back toward the seat.

05

Reverse Flow Develops

Downstream pressure acts in the closing direction and reinforces the seated position of the plug.

06

Backflow Is Blocked

The closed plug and seat interface prevent unwanted reverse product movement through the process line.

Typical Applications

  • Dairy product transfer and processing lines
  • Beverage and liquid-food production systems
  • Pump discharge and equipment-protection duties
  • Heat exchanger, pasteurizer and utility interfaces
  • Lines requiring automatic one-way hygienic flow
  • CIP circuits where reverse-flow protection is required

Selection Information

  • Required nominal size and pipe outside diameter
  • ISO or DIN welding-end execution
  • Product type and cleaning media
  • Normal pressure, pressure peaks and differential pressure
  • Operating and cleaning temperature
  • Stainless-steel grade, seal material and OEM reference

Information required for an accurate LKC-2 quotation

Provide the complete OEM Part Number whenever available, together with valve size, pipe standard, stainless-steel execution, seal material, operating pressure, temperature, product details and clear photographs of the installed valve or its nameplate.

Magnetic-Operated Model

EDF Hygienic Non-Return Valve

The EDF is a magnetic-operated hygienic Check Valve developed for applications requiring automatic one-way flow, compact construction and high sanitary performance. Its closing action is produced by magnetic force rather than a conventional mechanical spring.

EDF — Magnetic-Operated Check Valve
High-Hygiene Design
Forward Product Flow
Magnetic Closing Force
Hygienic Product Path
Automatic Backflow Protection
MODEL FAMILY: EDF

Magnetic Closing for Hygienic Process Protection

The EDF uses magnetic attraction to return the internal closing element to its seat. During forward flow, upstream differential pressure moves the valve element away from the seat. When forward pressure decreases or reverse pressure appears, magnetic force pulls the internal element back into the closed position and prevents backflow.

Magnetic Operation Closing action is generated by magnetic force.
Self-Acting Valve No pneumatic actuator or external control signal is required.
Backflow Prevention Automatically closes when reverse-pressure conditions develop.
High-Hygiene Use Designed for clean and sanitary processing applications.
Compact Construction Suitable for process areas with limited installation space.
Process Connections Connection execution must match the installed hygienic piping system.
EDF selection must be based on the exact OEM reference, nominal size, pipe standard, stainless-steel execution, seal specification, process pressure and product conditions.

Magnetic Operating Principle

The EDF opening and closing cycle is controlled by the balance between process differential pressure and magnetic closing force.

01

Closed at Rest

With no sufficient inlet pressure, magnetic attraction holds the internal valve element against the seat.

02

Forward Pressure Increases

Upstream differential pressure rises and begins to overcome the magnetic closing force.

03

Valve Opens

The internal element moves away from the seat and product flows in the permitted direction.

04

Valve Closes Automatically

When forward pressure falls or reverses, magnetic force returns the internal element to the seat.

Magnetic Closing Mechanism Eliminates the conventional spring principle and provides automatic return of the closing element.
Hygienic Process Protection Helps protect product lines and downstream equipment from reverse flow and cross-migration.
No External Actuator The valve responds directly to process pressure and magnetic force, reducing external control requirements.
Compact Installation Suitable for hygienic skids and process areas where available piping space is limited.
Automatic One-Way Flow Permits forward product movement and closes when the pressure condition no longer supports flow.
OEM-Specific Selection Correct replacement requires verification of model, size, material, connection standard and part number.
EDF Design Details

Construction, Hygiene & Engineering Advantages

The EDF magnetic-operated Non-Return Valve combines automatic backflow protection with a compact hygienic design. Proper selection depends on understanding its internal construction, process conditions, installation orientation and exact OEM execution.

Main EDF Components

The exact geometry may vary by nominal size and connection execution, but the EDF family generally relies on a compact set of hygienic and magnetic components to create the opening, closing and sealing functions.

Valve Body Stainless-steel pressure boundary containing the internal magnetic closing element and hygienic product passage.
Magnetic Element Generates the closing force that returns the movable element toward the seat when forward pressure decreases.
Movable Closing Element Lifts under forward differential pressure and returns automatically when the pressure balance changes.
Valve Seat Provides the shut-off interface that blocks reverse flow when the internal element is in the closed position.
Product-Wetted Surfaces Internal surfaces exposed to product and cleaning media, requiring suitable material and hygienic surface condition.
Internal Guide Maintains the correct movement and alignment of the closing element during repeated operating cycles.
Process Connections Connection ends must match nominal size, piping standard and the installed hygienic process line.
Sealing Interfaces Static and dynamic sealing areas must be verified for product, temperature, cleaning chemistry and pressure conditions.

Hygienic Product Path

The EDF is intended for sanitary process service where cleanability, product safety and controlled one-way flow are essential.

  • Compact internal flow path designed for hygienic product transfer.
  • Product-wetted stainless-steel surfaces suited to sanitary processing.
  • Automatic operation without external pneumatic actuation.
  • Suitable seal execution must be selected for product and CIP media.
  • Correct drainage and installation orientation support reliable hygiene.

CIP & Cleaning Considerations

The valve must be evaluated as part of the complete cleaning circuit, including flow velocity, cleaning temperature, chemistry and pressure.

  • Confirm that CIP pressure is sufficient to move and clean the internal element.
  • Verify elastomer and internal-material compatibility with cleaning chemicals.
  • Avoid installation positions that can trap product or cleaning solution.
  • Inspect sealing surfaces if leakage or incomplete closure is observed.
  • Follow OEM maintenance and replacement instructions for magnetic components.

Engineering Advantages of Magnetic Operation

Magnetic closing offers a different operating principle from a conventional spring-loaded Check Valve and may be preferred in selected high-hygiene process applications.

No Conventional Spring Closing force is produced magnetically, eliminating the traditional spring element from the operating principle.
Automatic Response The valve reacts directly to differential pressure and closes when forward pressure is no longer sufficient.
Compact Installation Compact geometry can simplify installation in skids, manifolds and limited piping spaces.
Process Protection Helps protect pumps, product lines and downstream equipment against unwanted reverse-flow conditions.
Hygienic Service Intended for clean processing duties where product safety and sanitary construction are important.
OEM-Specific Performance Opening behaviour and magnetic closing force depend on exact model, size and factory execution.

Installation Considerations

  • Install the valve according to the indicated flow direction.
  • Confirm whether the selected execution permits vertical, horizontal or both orientations.
  • Support connected piping to avoid transferring stress into the valve body.
  • Protect internal surfaces from welding debris, metal particles and construction contamination.
  • Allow sufficient access for inspection, disassembly and replacement of internal components.
  • Check that installation geometry supports complete drainage and CIP coverage.

Selection Considerations

  • Nominal size and actual pipe outside diameter
  • Connection standard and welding-end execution
  • Normal operating pressure and differential pressure
  • Product viscosity, solids content and flow behaviour
  • Operating and cleaning temperature
  • Stainless-steel grade, seal material and OEM Part Number

EDF Engineering Review Checklist

Review Item What Must Be Verified Risk if Incorrect Recommended Documentation
Flow Direction Confirm the permitted direction of product movement through the installed valve. Incorrect orientation may prevent opening or eliminate backflow protection. Installation drawing, valve marking or clear site photograph.
Nominal Size Verify valve size and actual pipe dimensions. Incorrect fit, welding mismatch or reduced process capacity. Pipe schedule, dimension drawing or OEM Part Number.
Pressure Differential Confirm available upstream pressure and downstream back pressure. Valve may fail to open fully or may close unexpectedly. Process data sheet and pump operating information.
Product Properties Review viscosity, solids, stickiness and product temperature. Increased pressure loss, incomplete closure or deposit formation. Product specification and operating description.
Cleaning Conditions Review CIP chemical, temperature, pressure and flow velocity. Seal damage, incomplete cleaning or reduced service life. CIP recipe and chemical compatibility data.
Material Execution Confirm stainless-steel grade and all product-contact materials. Corrosion, incompatibility or non-compliance with plant requirements. Material certificate, OEM data sheet or equipment record.
OEM Reference Match complete part number, model, size and connection execution. Wrong replacement valve or incompatible internal parts. Nameplate photo, original manual, invoice or spare-parts list.

Magnetic closing force is model-specific

The opening behaviour of an EDF valve depends on the relationship between process differential pressure and the magnetic closing force of the exact valve execution. This value should not be assumed from another nominal size or another Non-Return Valve family.

A magnetic valve is not automatically suitable for every product

Product viscosity, particles, crystallization, stickiness and cleaning behaviour can affect movement of the internal element and sealing performance. The complete process duty should therefore be reviewed before selecting EDF for a new installation.

LGN Non-Return Valves - Part 4B

Typical EDF Applications

The EDF magnetic-operated hygienic non-return valve is selected where automatic one-way flow protection and sanitary construction are required.

Dairy

Milk, cream, yogurt, cultured products, CIP return lines and hygienic utility systems.

Beverage

Juices, soft drinks, mineral water, brewing and filling process lines.

Pharmaceutical

Purified liquids and hygienic process loops requiring contamination prevention.

Cosmetics

Lotions, liquid soaps, emulsions and other sanitary transfer duties.

Food Processing

Sauces, edible liquids and general hygienic process systems.

Utility Services

Process water and other clean utility circuits where reverse flow must be prevented.

EDF Selection Guide

Parameter Why It Matters
OEM Part Number Ensures the exact magnetic execution and internal geometry.
Nominal Size Must match piping dimensions and process capacity.
Connection Standard ISO, DIN or other hygienic connection execution.
Operating Pressure Determines opening behaviour and process suitability.
Temperature Affects elastomer compatibility and service life.
Cleaning System Verify compatibility with CIP/SIP procedures where applicable.
Product Characteristics Viscosity, solids and crystallization behaviour influence valve performance.

Inspection & Preventive Maintenance

Routine Inspection

  • Check external leakage.
  • Confirm correct flow direction.
  • Inspect welds and connections.
  • Listen for abnormal operation.

Internal Inspection

  • Inspect sealing surfaces.
  • Check magnetic element condition.
  • Verify free movement of internal parts.
  • Replace worn seals.

During Shutdown

  • Clean all wetted components.
  • Inspect for corrosion or deposits.
  • Confirm proper reassembly.
  • Document maintenance history.
Engineering Recommendation: Replacement intervals should always follow the original equipment manufacturer's maintenance program and the plant's operating conditions rather than fixed calendar periods.

Information Required for an RFQ

  • Complete OEM model and part number
  • Valve size and connection standard
  • Operating pressure and temperature
  • Product description and viscosity
  • Seal material (if known)
  • Nameplate photo or assembly drawing
  • Required quantity
  • Delivery destination and project schedule

LKC-2 vs EDF Hygienic Non-Return Valves

Although both valves perform the same primary function—preventing reverse flow—they use different closing mechanisms and are selected for different engineering priorities.

Parameter LKC-2 EDF
Closing principle Spring-operated Magnetic-operated
Closing force Mechanical spring Permanent magnetic attraction
Opening method Process differential pressure Process differential pressure
External actuator Not required Not required
Typical hygienic use General food & beverage processing Selected high-hygiene process duties
Installation Depends on OEM orientation Depends on OEM orientation
OEM execution LKC-2 family EDF family

Engineering Comparison

Engineering Aspect Recommendation
General hygienic process lines LKC‑2 is commonly selected.
Magnetic closing requirement EDF should be evaluated.
Simple maintenance philosophy LKC‑2 may be preferred where spring-operated designs are standardized.
Compact magnetic solution EDF may provide advantages where specified by the OEM.
Replacement of existing valve Always replace with the exact OEM execution unless engineering approval is obtained.
Important: Neither valve is universally "better". Selection should be based on the process, OEM design, pressure conditions, product characteristics, cleaning requirements and spare-parts compatibility.

Which Valve Should I Choose?

Step 1
Identify the existing OEM valve family and part number.
➜
Step 2
Confirm pipe size, connection standard and operating conditions.
➜
Step 3
If the equipment specifies LKC‑2, replace with LKC‑2. If it specifies EDF, replace with EDF unless a complete engineering review approves a change.

Selection Matrix

Question Preferred Direction
Need to replace an installed LKC‑2? Use equivalent LKC‑2 OEM specification.
Need to replace an installed EDF? Use equivalent EDF OEM specification.
Designing a new hygienic line? Select after reviewing pressure, product, CIP strategy and manufacturer recommendations.
Unknown installed valve? Collect photos, nameplate, drawings and part numbers before ordering.
Technical Engineering Data

Specifications, Materials & Sizing Considerations

A hygienic Non-Return Valve must be selected from verified pressure, temperature, material, connection and process data. The values below distinguish published LKC-2 specifications from EDF parameters that must be confirmed against the exact OEM execution.

Published LKC-2 Technical Data

Reference values for the hygienic spring-operated LKC-2 valve family.

Maximum Product Pressure 10 bar Equivalent to 1,000 kPa under the published standard execution.
Maximum Temperature 140°C Published limit for the standard EPDM-sealed execution.
Minimum Temperature -10°C Confirm lower-temperature compatibility for the actual seal grade.
Approx. Opening Differential 0.06 bar Published approximate value for installation in a vertical pipe.
Internal Surface Finish Ra < 0.8 µm Published product-wetted internal surface-finish value.
Tube Standards ISO / DIN Available connection execution must be matched to the process line.

The opening differential is not the total system pressure drop

The approximate 0.06 bar value describes the pressure differential required to begin opening the vertically installed LKC-2 under the published configuration. Actual pressure loss during flow also depends on size, flow rate, fluid properties, valve position and pipe geometry.

LKC-2 Materials & Standard Construction

Product-contact material and seal selection must correspond to the process duty.

Component or Property Published Standard / Option Engineering Consideration
Product-Wetted Steel 1.4301 (AISI 304) or 1.4404 (AISI 316L) 316L is commonly evaluated for more demanding corrosion and hygienic duties.
Standard Product-Wetted Seals EPDM Confirm compatibility with product, temperature and cleaning chemistry.
Optional Seal Materials NBR or FPM Selection should be based on chemical, fat, oil and thermal exposure.
Internal Surface Finish Bright polished, Ra < 0.8 µm Surface condition must be protected during handling, welding and maintenance.
External Surface Finish Bright, machined Ra 1.6 Alternative finish requirements should be stated during quotation.
Body Assembly Two body parts assembled by clamp ring Clamp and seal condition should be checked during maintenance.
Closing Mechanism Spring-loaded valve plug Spring, guide and plug condition affect repeatable opening and closing.
Connections Weld and clamp ends for ISO and DIN tubing Confirm exact tube outside diameter—not only the nominal DN designation.

Seal Selection Guidance

Seal materials should never be chosen only from temperature limits. Product composition and CIP chemistry are equally important.

  • EPDM: commonly selected for hot water, steam-related cleaning and many water-based hygienic duties.
  • NBR: commonly assessed for oils and fats, subject to temperature and chemical limitations.
  • FPM: often assessed for chemical and higher-temperature resistance, but must still be checked against CIP media.
  • Use the exact OEM seal kit for the valve size and material execution.

EDF Technical Data Policy

EDF is identified as a magnetic-operated Non-Return Valve for high-hygiene applications. Numerical performance data should be taken only from the matching EDF OEM data sheet.

  • Verify complete EDF model and Part Number.
  • Request pressure and temperature limits for the exact size.
  • Confirm magnetic opening and closing characteristics.
  • Verify material, surface finish and process connections.
  • Confirm CIP/SIP suitability and permitted installation orientation.

LKC-2 vs EDF Specification Status

How technical values should be handled during selection and quotation.

Parameter LKC-2 EDF Required Procurement Action
Operating Principle Spring-operated Magnetic-operated Do not interchange mechanisms without engineering approval.
Maximum Product Pressure Published standard value: 10 bar Confirm exact OEM value State normal and maximum system pressure in RFQ.
Temperature Range -10°C to 140°C for published EPDM execution Confirm exact OEM value State product, CIP and SIP temperatures separately.
Opening Characteristic Approx. 0.06 bar opening differential when vertically installed Magnetic force is execution-specific Request pressure-drop or opening data for the selected size.
Steel Grade 304 or 316L published Confirm exact OEM execution Request material certificates where required.
Seal Material EPDM standard; NBR/FPM options published Confirm exact OEM execution Provide product and cleaning-chemical information.
Connection Standard ISO or DIN; weld/clamp options published Confirm exact OEM execution Provide dimensions or a drawing to prevent connection mismatch.

Do not assign LKC-2 values to EDF

Both products are Non-Return Valves, but their closing mechanisms and model-specific performance differ. LKC-2 pressure, temperature, opening-differential or material values must not be presented as EDF specifications unless the EDF OEM documentation explicitly confirms them.

Engineering Sizing Notes

A Check Valve should be sized for stable operation—not simply selected by matching the pipe nominal size.

Available ΔP = Pupstream − Pdownstream Available differential pressure must overcome the valve closing force and the dynamic pressure loss at the required flow rate.
01
Define Required Flow Record normal, minimum and maximum flow rather than only design capacity.
02
Establish Fluid Properties Review density, viscosity, temperature, solids and tendency to crystallize or stick.
03
Calculate Available Pressure Consider pump curve, static head, downstream pressure and all line losses.
04
Verify OEM Performance Check pressure-drop and opening behaviour for the exact valve size and execution.

A valve that is too large may also perform poorly

Oversizing can result in low internal velocity, incomplete movement, unstable operation and product accumulation. Undersizing can create excessive pressure loss, high velocity and insufficient process capacity. Final sizing should therefore use manufacturer flow data.

Technical Data Required Before Quotation

A complete RFQ reduces the risk of receiving an incompatible valve or service kit.

IdentificationManufacturer, model, full Part Number and nameplate photograph.
DimensionsNominal size, tube OD, wall thickness and connection standard.
Pressure DataNormal pressure, maximum pressure and downstream back pressure.
Temperature DataProduct, CIP and SIP temperatures and exposure duration.
Media DetailsProduct composition, viscosity, solids and cleaning chemicals.
Compliance NeedsMaterial certificate, food-contact, surface-finish or plant-standard requirements.
OEM Reference Tables

LGN Non-Return Valves — OEM Part Numbers

Tetra Pak / Alfa Laval reference list for LKC-2 spring-operated and EDF magnetic-operated hygienic non-return valves. The tables below reproduce only the model, size, material, connection and OEM part-number information shown in the supplied manufacturer screenshots.

40 Total OEM part numbers
26 LKC-2 spring-operated references
14 EDF magnetic-operated references

LKC-2 Spring-Operated — SMS Welding Ends

EPDM seals · 304 or 316L stainless steel

12 OEM references
Valve family Connection Material Denomination Size A H OEM Part No.
LKC-2SMS welding ends304LKC-2-W-25.0-304 EPDM25.0 mm62.5826-9612 22 0001
LKC-2SMS welding ends304LKC-2-W-38.0-304 EPDM38.0 mm7595.56-9612 22 0002
LKC-2SMS welding ends304LKC-2-W-51.0-304 EPDM51.0 mm87.51096-9612 22 0003
LKC-2SMS welding ends304LKC-2-W-63.5-304 EPDM63.5 mm951376-9612 22 0004
LKC-2SMS welding ends304LKC-2-W-76.1-304 EPDM76.1 mm1151486-9612 22 0005
LKC-2SMS welding ends304LKC-2-W-101.6-304 EPDM101.6 mm1551646-9612 22 0006
LKC-2SMS welding ends316LLKC-2-W-25.0-316L EPDM25.0 mm62.5826-9612 22 0007
LKC-2SMS welding ends316LLKC-2-W-38.0-316L EPDM38.0 mm7595.56-9612 22 0008
LKC-2SMS welding ends316LLKC-2-W-51.0-316L EPDM51.0 mm87.51096-9612 22 0009
LKC-2SMS welding ends316LLKC-2-W-63.5-316L EPDM63.5 mm951376-9612 22 0010
LKC-2SMS welding ends316LLKC-2-W-76.1-316L EPDM76.1 mm1151486-9612 22 0011
LKC-2SMS welding ends316LLKC-2-W-101.6-316L EPDM101.6 mm1551646-9612 22 0012

LKC-2 Spring-Operated — DIN Welding Ends

EPDM seals · 304 or 316L stainless steel

14 OEM references
Valve family Connection Material Denomination Nominal size A H OEM Part No.
LKC-2DIN welding ends304LKC-2-W-25-304 EPDMDN2562.5826-9612 22 0040
LKC-2DIN welding ends304LKC-2-W-32-304 EPDMDN327595.56-9612 22 0041
LKC-2DIN welding ends304LKC-2-W-40-304 EPDMDN407595.56-9612 22 0042
LKC-2DIN welding ends304LKC-2-W-50-304 EPDMDN5087.51096-9612 22 0043
LKC-2DIN welding ends304LKC-2-W-65-304 EPDMDN65951376-9612 22 0044
LKC-2DIN welding ends304LKC-2-W-80-304 EPDMDN801151486-9612 22 0045
LKC-2DIN welding ends304LKC-2-W-100-304 EPDMDN1001551646-9612 22 0046
LKC-2DIN welding ends316LLKC-2-W-25-316L EPDMDN2562.5826-9612 22 0047
LKC-2DIN welding ends316LLKC-2-W-32-316L EPDMDN327595.56-9612 22 0048
LKC-2DIN welding ends316LLKC-2-W-40-316L EPDMDN407595.56-9612 22 0049
LKC-2DIN welding ends316LLKC-2-W-50-316L EPDMDN5087.51096-9612 22 0050
LKC-2DIN welding ends316LLKC-2-W-65-316L EPDMDN65951376-9612 22 0051
LKC-2DIN welding ends316LLKC-2-W-80-316L EPDMDN801151486-9612 22 0052
LKC-2DIN welding ends316LLKC-2-W-100-316L EPDMDN1001551646-9612 22 0053

EDF Magnetic-Operated — SMS Welding Ends

EPDM seals · 316L stainless steel

6 OEM references
Valve family Connection Material Manufacturer description Size OEM Part No.
EDFSMS welding ends316LCheck valve, EDF W 25 EPDM25 mm70000186158
EDFSMS welding ends316LCheck valve, EDF W 38 EPDM38 mm70000186121
EDFSMS welding ends316LCheck valve, EDF W 51 EPDM51 mm70000186156
EDFSMS welding ends316LCheck valve, EDF W 63.5 EPDM63.5 mm70000186171
EDFSMS welding ends316LCheck valve, EDF W 76.1 EPDM76.1 mm70000186120
EDFSMS welding ends316LCheck valve, EDF W 101.6 EPDM101.6 mm70000186169

EDF Magnetic-Operated — DIN Welding Ends

EPDM seals · 316L stainless steel

8 OEM references
Valve family Connection Material Manufacturer description Nominal size OEM Part No.
EDFDIN welding ends316LCheck valve, EDF W DN10 EPDMDN1070000185933
EDFDIN welding ends316LCheck valve, EDF W DN15 EPDMDN1570000185934
EDFDIN welding ends316LCheck valve, EDF W DN25 EPDMDN2570000186182
EDFDIN welding ends316LCheck valve, EDF W DN40 EPDMDN4070000186175
EDFDIN welding ends316LCheck valve, EDF W DN50 EPDMDN5070000186150
EDFDIN welding ends316LCheck valve, EDF W DN65 EPDMDN6570000186176
EDFDIN welding ends316LCheck valve, EDF W DN80 EPDMDN8070000186151
EDFDIN welding ends316LCheck valve, EDF W DN100 EPDMDN10070000186128
Reference note: Exactly 40 OEM part numbers are included: 26 LKC-2 references and 14 EDF references. No additional or inferred part numbers have been added.

Frequently Asked Questions

Answers to the most common engineering, maintenance and purchasing questions about hygienic Non-Return (Check) Valves.

What is a hygienic Non-Return Valve?
A hygienic Non-Return Valve automatically prevents reverse flow while allowing forward product flow, protecting pumps, pipelines and sanitary processing equipment.
How does an LKC-2 valve work?
LKC-2 uses a spring-loaded closing element. Forward differential pressure compresses the spring to open the valve, while the spring closes it when flow stops or reverses.
How does the EDF valve work?
EDF uses a magnetic closing mechanism rather than a conventional spring. The exact operating characteristics depend on the specific OEM model.
Can LKC-2 and EDF replace each other?
Not automatically. Replacement should match the original OEM model unless an engineering review confirms compatibility.
Which industries use hygienic check valves?
Food, dairy, beverage, pharmaceutical, biotechnology and cosmetic manufacturing are common applications.
Can these valves be used with CIP systems?
Yes, when the valve execution and seal materials are suitable for the plant's cleaning procedure.
Can they be used with SIP?
Some configurations can be used in SIP processes, but the permitted temperature and seal materials must be confirmed for the exact model.
Which seal material should I choose?
EPDM, NBR or FPM should be selected according to the product, cleaning chemicals and operating temperature.
Why is my valve leaking?
Common causes include worn seals, damaged seating surfaces, contamination, incorrect installation or unsuitable process conditions.
Why does valve chatter occur?
Chatter may result from unstable flow, insufficient differential pressure, oversizing or pulsating pump operation.
How often should the valve be serviced?
Maintenance intervals should follow the OEM recommendations and the plant's operating conditions rather than fixed calendar periods.
Can the valve be installed horizontally?
Installation orientation depends on the specific model and manufacturer instructions.
What information is required for a quotation?
Provide the OEM part number, valve size, connection standard, operating pressure, temperature, product details and, if possible, a nameplate photo.
How do I choose the correct valve size?
Selection should consider flow rate, pressure loss, fluid properties and the manufacturer's technical data—not pipe size alone.
Does LGN supply spare parts?
Yes. LGN can assist with complete valves, seal kits and OEM spare parts for many hygienic process applications.
Engineering Tip: For the most reliable recommendation, include your valve nameplate, OEM part number, process medium, operating pressure, temperature and connection standard when requesting a quotation.
Technical & Commercial Support

Need Help Selecting the Right Hygienic Non-Return Valve?

LGN Group supplies hygienic Non-Return (Check) Valves, OEM spare parts, seal kits and engineered flow-control solutions for dairy, beverage, food, pharmaceutical, biotechnology and cosmetic production facilities. Whether you are replacing an existing valve or designing a new processing line, our team can help identify the appropriate solution based on your operating conditions and verified OEM specifications.

Industries Served

Dairy, beverage, food, pharmaceutical, biotechnology and cosmetic process applications.

Products & Services

Complete valves, OEM spare parts, seal kits, technical support and carefully reviewed replacement recommendations.

Engineering Support

Valve identification, material review, sizing guidance and support for hygienic process applications.

To receive the most accurate quotation, please include:
OEM manufacturer, model and complete Part Number
Valve size, tube dimensions and connection standard
Normal and maximum operating pressure
Product, CIP and SIP temperatures
Process medium, viscosity and cleaning requirements
Nameplate photograph or technical drawing, when available
Required quantity and preferred delivery schedule
Destination country and requested documentation
Request a Quote Contact LGN Engineers

LGN Group provides industrial process equipment and hygienic flow components for demanding production environments. Our team supports customers with OEM spare-parts sourcing, technical documentation and engineering assistance to help maintain reliable, efficient and hygienic process operations.