Product Overview

The NOIKE-AH Mechanical Paddle Flow Switch NK-01D is a reliable flow monitoring device designed for liquid and gas applications in industrial pipelines with diameters ≥25 mm. It features a spring-supported paddle mechanism that mechanically actuates an internal microswitch when the preset flow rate is reached.

With a completely isolated mechanical and electrical structure, the switch provides dependable switching performance, low pressure loss, and excellent resistance to contamination. A standard set of five interchangeable paddles allows flexible adjustment for different pipe sizes and flow conditions, making installation simple and cost-effective.

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Working Principle

The mechanical flow switch NK-01D operates using a spring-supported paddle mechanism.

As fluid flows through the pipeline, it pushes against the stainless steel paddle. When the flow reaches the preset switching point, the paddle moves against the spring force and mechanically actuates the built-in microswitch.

Once the flow decreases below the preset value, the spring returns the paddle to its original position and the switch resets automatically.

This purely mechanical operating principle provides reliable flow detection without requiring complex electronic sensing components.

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Key Features

• Mechanical paddle flow detection
• Spring-supported paddle mechanism
• SPDT (Normally Open + Normally Closed) output
• Complete isolation between mechanical and electrical components
• Low pressure loss during operation
• Wide flow adjustment range
• Five interchangeable paddles included as standard
• Suitable for various pipe diameters and installation conditions
• Easy adjustment and installation
• High switching reliability
• Excellent repeatability
• Strong resistance to contamination
• Maintenance-friendly design

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Technical Specifications

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Materials

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Typical Applications

The mechanical paddle flow switch NK-01D series is suitable for flow monitoring and equipment protection in a wide range of industrial systems, including:

• Industrial automation
• Mechanical equipment
• Air compressors
• Refrigeration systems
• HVAC systems
• Cooling water pipelines
• Lubrication systems
• Water circulation systems
• General industrial process control

Suitable for both liquid and gas applications in pipelines with diameters of 25 mm and above.

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Product Advantages

Reliable Mechanical Operation

The spring-supported paddle directly actuates an internal microswitch, ensuring stable and dependable flow detection without complex electronics.

Flexible Flow Adjustment

Five interchangeable paddles supplied as standard allow the switch to accommodate different pipe sizes and operating conditions.

Low Pressure Loss

The optimized paddle structure minimizes pressure drop while maintaining reliable switching performance.

Excellent Durability

Stainless steel wetted components provide good corrosion resistance and long service life in industrial environments.

Easy Installation

Threaded R1 process connection and terminal wiring enable quick installation and convenient maintenance.

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Why Choose the NOIKE-AH Mechanical Paddle Flow Switch NK01D?

The NOIKE-AH Mechanical Paddle Flow Switch NK01D offers a simple, durable, and cost-effective solution for industrial flow monitoring. With its SPDT switching output, low pressure loss, interchangeable paddles, and robust stainless steel construction, it is ideal for protecting pumps, compressors, cooling systems, and other industrial equipment where dependable flow detection is essential.

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Wiring Diagram

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Installation direction

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Size chart

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Frequently Asked Questions (FAQ)

1. How does a mechanical paddle flow switch NK01D work?

A mechanical paddle flow switch NK01D uses a spring-supported stainless steel paddle installed inside the pipeline. As fluid flows through the pipe, it pushes the paddle. When the flow reaches the preset switching point, the paddle mechanically actuates an internal microswitch, generating an electrical output signal. When the flow decreases below the set point, the spring automatically returns the paddle to its original position.

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2. What media can this mechanical flow switch monitor?

The flow switch is suitable for both liquids and gases, including:

• Water
• Cooling water
• Lubricating oil
• Hydraulic oil
• Air
• Compressed air
• Other compatible non-corrosive media

For highly viscous, corrosive, or contaminated media, please consult NOIKE-AH before selecting a model.

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3. What pipe sizes are supported?

This model is designed for pipelines with diameters of 25 mm (1 inch) or larger.

Five interchangeable paddles are supplied as standard, allowing the switch to be adjusted for different pipe sizes and flow conditions.

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4. Can the switching point be adjusted?

Yes.

The switching point can be adjusted by selecting the appropriate paddle size and mechanical adjustment according to the required flow rate. NOIKE-AH can also help preset the switching value before shipment if the application details are provided.

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5. Does the flow switch require a power supply?

No.

The sensing mechanism is completely mechanical. Only the internal SPDT microswitch requires connection to the external control circuit for signal output.

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6. What output signal does the switch provide?

The switch provides an SPDT (Single Pole Double Throw) output, including:

• Normally Open (NO)
• Normally Closed (NC)

Contact Rating:

• 250 VAC, 3 A

This allows easy integration with PLCs, relays, alarms, and industrial control systems.

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7. What is the maximum working pressure?

The maximum working pressure is 16 bar, making it suitable for a wide range of industrial water, oil, and gas applications.

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8. Is the flow switch suitable for dirty or contaminated media?

Yes.

The paddle-type mechanical design offers strong resistance to contamination and provides reliable operation in many industrial environments.

However, media containing large solid particles or fibrous materials may affect performance and should be evaluated before installation.

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9. Does installation require straight pipe sections?

For the best switching accuracy, it is recommended to install the flow switch in a section of pipeline with stable flow conditions and away from elbows, valves, and pumps whenever possible.

Proper installation helps improve repeatability and switching reliability.

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10. What industries commonly use this mechanical flow switch?

Typical applications include:

• Industrial automation
• Pump protection
• Cooling water systems
• HVAC systems
• Refrigeration equipment
• Air compressor systems
• Lubrication systems
• Hydraulic systems
• Machinery manufacturing
• General process control

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11. What maintenance is required?

Very little maintenance is required.

It is recommended to periodically inspect the paddle for contamination or scale buildup, especially in systems carrying dirty water or process fluids.

Routine cleaning helps maintain long-term switching accuracy.

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12. Why choose a mechanical paddle flow switch instead of an electronic flow switch?

A mechanical paddle flow switch is ideal when users need:

• No electronic sensing components
• Simple and reliable operation
• Cost-effective flow monitoring
• Easy installation
• High durability
• Low maintenance
• Reliable switching in industrial pipelines

For applications requiring higher sensitivity, adjustable flow indication, digital communication, or monitoring of very low flow rates, a thermal dispersion electronic flow switch may be a better choice.

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13. Can NOIKE-AH customize the flow switch?

Yes.

NOIKE-AH offers customization services based on application requirements, including:

• Different process connections
• Various paddle configurations
• Customized switching settings
• Special materials
• OEM and private label services