Oval Gear Flow Meter NKGF-LC-A Series | Positive Displacement Flow Meter

Brand：NOIKE-AH
Model：NKGF-LC-A Series

Specification

Product Overview

The Oval Gear Flow Meter NKGF-LC-A Series is a positive displacement flow meter designed for accurate measurement of high-viscosity liquids. It is suitable for media such as heavy fuel oils, resins, and polyols, providing stable and repeatable volumetric flow measurement.

The meter features a local mechanical counter display, pulse output for remote monitoring, and an Ex ia IIC T6 Ga explosion-proof design, making it suitable for industrial environments where accurate liquid measurement and reliable operation are required.

Working Principle

The oval gear flow meter NKGF-LC-A operates using the positive displacement measuring principle. As liquid flows through the measuring chamber, the pair of precision oval gears rotates under the pressure of the flowing medium. Each rotation displaces a fixed volume of liquid, allowing the flow meter to calculate the total volumetric flow accurately.

Because every gear rotation represents a known liquid volume, the meter provides high measurement accuracy and excellent repeatability, especially when measuring high-viscosity fluids.

Product Features

Positive displacement measuring principle
Suitable for high-viscosity liquids
Local mechanical totalizer display
Pulse output for remote monitoring
High measurement accuracy
Excellent repeatability
Explosion-proof design (Ex ia IIC T6 Ga)
Multiple housing and gear material options
Wide viscosity measurement range

Applications

The NKGF-LC-A Series is suitable for measuring:

Heavy fuel oils
Resins
Polyols

Typical industrial applications include:

Chemical processing
Oil and fuel transfer
Resin production
High-viscosity liquid metering
Process flow monitoring

Technical Specifications

Parameter	Specification
Measuring Principle	Positive Displacement
Accuracy	±0.5% (calibrated at 20°C)
Repeatability	±0.1%
Bore Size	DN10–DN100
Housing Material	Cast Iron / 316L Stainless Steel
Gear Material	304 / 316 Stainless Steel
Bearing Material	Tungsten Carbide
Viscosity Range	5–100,000 cP
Pressure Rating	1.6 MPa (Standard), 4.0 MPa (High-pressure Version)
Medium Temperature	-10°C to +120°C
Ambient Temperature	-20°C to +60°C
Pulse Output	NPN Open Collector
Output Power	12 VDC, 100 mA Max
Frequency Range	0–500 Hz
Explosion-proof Rating	Ex ia IIC T6 Ga

Installation Requirements

For optimum measurement performance:

Install the meter according to the flow direction arrow on the housing.
Maintain a minimum upstream straight pipe length of 5× pipe diameter.
Maintain a minimum downstream straight pipe length of 3× pipe diameter.
Install an 80 μm filter upstream to protect the measuring gears.

Unsuitable Media

The flow meter is not suitable for:

Fluids containing abrasive particles larger than 50 μm
Hydrofluoric acid
Concentrated alkalis
Liquid CO₂
Liquid ammonia

Maintenance

Zero Calibration

Disconnect the pulse output.
Verify that the mechanical counter is correctly aligned.

Gear Inspection

Inspect gear wear every 2,000 operating hours.
Replace the gears if the backlash exceeds 0.1 mm.

Why Choose the Oval Gear Flow Meter NKGF-LC-A ?

The NKGF-LC-A Series combines the advantages of positive displacement technology with durable construction for reliable measurement of high-viscosity liquids.

High Accuracy

Provides ±0.5% accuracy and ±0.1% repeatability for stable volumetric flow measurement.

Excellent Performance for High-Viscosity Media

Designed for liquids with viscosities ranging from 5 cP to 100,000 cP, making it suitable for demanding industrial processes.

Remote Monitoring Capability

Supports pulse output for integration with monitoring and control systems while retaining a local mechanical counter.

Industrial Reliability

Available in cast iron or stainless steel construction with tungsten carbide bearings for long-term operation.

Application Case

Resin Metering in Chemical Production

In resin manufacturing, accurate dosing of high-viscosity liquids is essential for maintaining product consistency and process efficiency. The Oval Gear Flow Meter NKGF-LC-A measures resin flow using the positive displacement principle, ensuring stable volumetric measurement even when fluid viscosity changes during production.

The local mechanical display allows operators to verify total flow on site, while the pulse output enables remote monitoring through PLC or control systems. Installing an upstream filter and following the recommended straight pipe requirements helps maintain measurement stability and extend service life.

Frequently Asked Questions (FAQ)

1. What measuring principle does this flow meter use?

It uses the positive displacement measuring principle with precision oval gears.

2. Which liquids can it measure?

It is designed for high-viscosity liquids, including heavy fuel oils, resins, and polyols.

3. Does the meter provide remote output?

Yes. It provides an NPN pulse output for remote monitoring.

4. What is the viscosity range?

5–100,000 cP.

5. Is an explosion-proof version available?

Yes. The standard configuration includes Ex ia IIC T6 Ga explosion protection.

6. How often should the gears be inspected?

Gear wear should be checked every 2,000 operating hours.

7. Which media should be avoided?

The meter should not be used with abrasive liquids containing particles larger than 50 μm, hydrofluoric acid, concentrated alkalis, liquid CO₂, or liquid ammonia.

Optional Services

Customized material selection
High-pressure version
Technical selection support
Installation guidance
Factory calibration

Industries Served

Suitable for applications in:

Chemical Processing
Petroleum Industry
Resin Manufacturing
Industrial Liquid Metering
Process Automation