A new member of the electromagnetic flow meter family is the insertion-type flow meter. Due to its simple structure, lightweight design, easy installation, low maintenance, and affordable price, it has become very popular among engineers and end users alike.
l The sensor (probe) is inserted directly into the measured pipeline. Compared to traditional flange-mounted electromagnetic flow meters, it offers advantages such as compact size, easier installation, and lower investment cost.
l The insertion depth of the sensor is only 10% to 12.5% of the pipe diameter, resulting in no pressure loss. It is especially suitable for large-diameter pipelines and provides excellent cost-performance.
l No clogging, no wear parts, and maintenance-free.
l The sensor can be made as a submersible type (IP68), making it ideal for installation on buried pipelines in industrial environments.
l Explosion-proof versions are available.
l Supports current and pulse signal output with a stable zero point.
l Can measure flow rates as low as 0.1 m/s (or even lower), with a minimum conductivity requirement of ≥20 μS/cm.
l Sensors can be supplied with mounting accessories for easy on-site installation.
l Measurement accuracy is relatively lower, typically around ±1%.
1. Although insertion-type electromagnetic flow meters can typically measure flow velocities as low as 0.1 m/s, the actual minimum flow velocity in a given application should still be carefully evaluated to ensure accurate measurement at low flow conditions.
2. A straight pipe length of at least 5D upstream and 3D downstream of the flow meter is required (D = nominal diameter of the pipe).
3. If deposits such as sludge or sediment are present in the pipeline, the fluid should maintain a sufficiently high flow velocity to prevent buildup. This is especially important in situations where deposits could insulate the sensor electrodes. In such cases, sensors with replaceable electrodes (removable online) should be considered.
4. For applications with wide flow variations or where the fluid velocity frequently falls below the meter’s minimum required level, consider reducing the pipe size or installing two meters in parallel—one large and one small.
5. Like standard electromagnetic flow meters, insertion-type magnetic flow meters are best installed on vertical pipelines. This helps prevent suspended solids from settling on the electrodes and ensures that oil components in the fluid rise out of the measurement zone. If horizontal installation is necessary, the electrodes should be aligned along the horizontal axis to prevent air bubbles from interfering with the measurement.
6. When the pipeline cannot be kept full of fluid, a V-shaped pipe layout may be used. This is especially suitable for wastewater applications where solids are present and the pipe is not completely filled.
7. Since the signal from the electrodes is very low (in the millivolt range), grounding currents must not be allowed to pass near the measuring electrodes.
8. When installing an insertion-type magnetic flow meter on non-metallic pipelines (such as ceramic or plastic), the section of the pipe where the meter is installed should be made of metal.
The insertion-type electromagnetic flow meter offers numerous advantages, including simple installation, wide applicability, reliable measurement performance, and ease of retrofitting older systems. It is widely used for measuring flow rates of various water-based media—such as fresh water, circulating water, and wastewater—where flow conditions fluctuate. It plays an effective role in water usage balancing and metering for industrial systems.
Designed to measure conductive liquids, insertion-type flow meters are especially well-suited for large-diameter pipelines and are widely applied across industries such as petroleum, chemical, metallurgy, power, paper, food processing, and water treatment.