NKFD-B Digital Mass Flow Meter / Controller (Large Range)

Direct Answer

The NKFD-B Digital Mass Flow Meter / Controller uses a thermal measurement principle to measure the mass flow rate of gases. It features fast response, high accuracy, short warm-up time, low zero drift, and high reliability. The product adopts a pipeline bypass structure and is suitable for various low- and high-pressure pipelines, with flow ranges including 500, 1000, 2000, and 3000 SLM. It also supports digital signal input/output and can be used with a flow computer for flow control or display.

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Key Takeaways

• Uses a thermal measurement principle with fast response and high accuracy.
• Uses a pipeline bypass structure that is not easily blocked.
• Suitable for various low- and high-pressure pipelines.
• Features short warm-up time, low zero drift, and high reliability.
• Supports digital signal input/output and can be used with a flow computer for flow control or display.
• Supports RS232, RS485, and MODBUS communication.
• Available flow ranges include 500 SLM, 1000 SLM, 2000 SLM, and 3000 SLM.

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What Is the NKFD Digital Mass Flow Meter / Controller?

The NKFD Digital Mass Flow Meter / Controller is an instrument designed for gas mass flow measurement and control.

The NKFD mass flow controller consists of components including a mass flow sensor, laminar flow element, flow control valve, and amplifier/control circuit.

The measurement principle uses the heat transferred by the flowing fluid. The temperature distribution on the wall of the measuring capillary changes, and the thermal conduction distribution effect is used to measure the mass flow rate.

The NKFD series includes:

• NKFD-BM: Mass Flow Meter
• NKFD-BC: Mass Flow Controller

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How Does the NKFD Mass Flow Meter / Controller Work?

The NKFD uses a thermal principle based on the temperature difference before and after heat transfer through a capillary to measure the mass flow rate of gas.

The operating process can be summarized as follows:

1. Gas flows through the measuring passage.
2. Heat is transferred by the flowing fluid.
3. A temperature difference is generated before and after the measuring capillary.
4. The sensor detects the corresponding flow signal.
5. The sensor signal is amplified.
6. The amplified signal is compared with the preset voltage.
7. The resulting difference drives the control valve.
8. The flow through the passage is controlled in a closed loop so that the actual flow rate is equal to the set flow rate.

For the NKFD mass flow controller, the core function is to achieve closed-loop flow control through mass flow detection, signal comparison, and control-valve adjustment.

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Key Features of the NKFD Digital Mass Flow Meter / Controller

1. Thermal Measurement Principle

The NKFD uses a thermal measurement principle for mass flow measurement, providing fast response and high accuracy.

2. Pipeline Bypass Structure

The product adopts a pipeline bypass structure and is not easily blocked.

3. Suitable for Low- and High-Pressure Pipelines

The product is suitable for various low- and high-pressure pipelines.

4. Short Warm-Up Time

The NKFD features a short warm-up time, low zero drift, and high reliability.

5. Digital Input / Output

The product supports digital input/output and can be used with a flow computer for flow control or flow display.

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Applications

The NKFD Digital Mass Flow Meter / Controller can be used in the following fields:

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NKFD Technical Specifications

Mass Flow Meter and Mass Flow Controller Specifications

Note: The original technical specification table states the range as 300 SLM–3000 SLM, while the product selection table lists 500 SLM, 1000 SLM, 2000 SLM, and 3000 SLM. Both values have been retained according to the original product information and have not been independently modified.

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NKFD Product Dimensions

The NKFD series includes the following product configurations:

• NKFD-BM Mass Flow Meter
• NKFD-BC Mass Flow Controller

The dimensions shown in the product drawing are in mm. Please refer to the product dimensional drawing for detailed dimensions.

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NKFD Product Selection

Series Number

NKFD-B

Product Type

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Pressure Resistance Range

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Display

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Flow Range

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Measured Medium

Refer to the gas density parameter table.

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Flow Input Signal

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Output Signal

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Power Supply

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Communication

The product also supports the MODBUS protocol.

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Sealing Material

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Process Connection

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NKFD Model Example

The model selection example shown in the original product information is:

NKFD-B C M N 500L 007 A1 B1 5 8 V H

The model code consists of selection items including the series number, product type, pressure resistance range, display configuration, flow range, selection code, input signal, output signal, power supply, communication method, sealing material, and process connection.

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Difference Between the NKFD Mass Flow Meter and Mass Flow Controller

The NKFD series includes both mass flow meters and mass flow controllers.

NKFD-BM Mass Flow Meter

The NKFD-BM is designed for mass flow measurement. The technical specification lists a 100:1 turndown ratio and a response time of less than 0.8 seconds.

NKFD-BC Mass Flow Controller

The NKFD-BC performs mass flow measurement and uses a control valve to regulate the flow rate. Its controller control range is 50:1, and its response time is less than 2 seconds.

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Frequently Asked Questions

1. What measurement principle does the NKFD Digital Mass Flow Meter use?

The NKFD uses a thermal principle based on the temperature difference before and after heat transfer through a capillary to measure gas mass flow.

2. What types of pipelines is the NKFD Mass Flow Meter suitable for?

The NKFD is suitable for various low- and high-pressure pipelines.

3. What flow ranges are available for the NKFD?

According to the product selection table, the available flow ranges include:

• 500 SLM
• 1000 SLM
• 2000 SLM
• 3000 SLM

4. What communication interfaces does the NKFD support?

The NKFD supports RS232, RS485, and the MODBUS protocol.

5. What input signals are supported by the NKFD?

The available flow input signals include:

• 0–5 VDC
• 4–20 mA
• 1–5 VDC

6. What output signals are supported by the NKFD?

The available output signals include:

• 0–5 VDC
• 4–20 mA
• 1–5 VDC

7. What is the difference between the NKFD Mass Flow Meter and Mass Flow Controller?

The NKFD-BM is a mass flow meter designed for mass flow measurement. The NKFD-BC is a mass flow controller consisting of a mass flow sensor, laminar flow element, flow control valve, and amplifier/control circuit, and it uses the control valve to achieve closed-loop flow control.

8. What material is used for the NKFD chamber?

The chamber material is 316L.

9. What process connections are available for the NKFD?

The product supports φ12, 3/4″, and flange mounting. Other connection options are available by contacting the manufacturer.

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How to Select an NKFD Mass Flow Meter / Controller

When selecting an NKFD product, determine the following configuration options according to the product selection table:

1. Product type: Mass Flow Meter or Mass Flow Controller
2. Pressure resistance: 3 MPa or 10 MPa — 10 MPa for the Mass Flow Meter only
3. Display: Without display or with display
4. Flow range: 500, 1000, 2000, or 3000 SLM
5. Flow input signal: 0–5 VDC, 4–20 mA, or 1–5 VDC
6. Output signal: 0–5 VDC, 4–20 mA, or 1–5 VDC
7. Power supply: ±15 VDC or 24 VDC
8. Communication: RS485 or RS232
9. Sealing material: Fluororubber, PTFE, nitrile rubber, or other
10. Process connection: φ12, 3/4″, flange mounting, or other

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Conclusion

The NKFD Digital Mass Flow Meter / Controller uses a thermal mass flow measurement principle and features fast response, high accuracy, short warm-up time, low zero drift, and high reliability. The product adopts a pipeline bypass structure and can be used in various low- and high-pressure pipelines, providing solutions for both mass flow measurement and closed-loop flow control.

The NKFD series supports 500–3000 SLM flow-range configurations, RS232/RS485 communication, the MODBUS protocol, and 0–5 V, 4–20 mA, and 1–5 V signal options. Applications include vacuum, coating, solar energy, semiconductor, petroleum and petrochemical, combustion and metallurgy, gas generation and distribution, environmental protection, and various instrument analysis applications.

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RFQ / Product Inquiry

If you need to confirm the flow range, pressure range, signal type, communication method, sealing material, or process connection of the NKFD Digital Mass Flow Meter / Controller, please select the required configuration according to the product selection table and contact the manufacturer for confirmation.

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