Detailed Explanation of Prosonic Clamp-on Installation Position
The clamp-on installation method of the Prosonic ultrasonic flowmeter is widely popular due to its non-invasive measurement. The correct installation position is the primary condition for ensuring measurement accuracy. This article is Part 1 of the clamp-on installation series, focusing on the principles for selecting the installation position.
Basic Requirements for the Installation Position
1. Pipe Conditions
- The pipe must be full of liquid to avoid bubbles or deposits affecting the ultrasonic signal.
- The pipe material should be uniform, without severe corrosion or lining detachment.
- It is recommended to choose vertical or horizontal pipes, but for horizontal pipes, the top and bottom areas should be avoided.
2. Straight Pipe Section Requirements
To ensure stable flow conditions, the sensor installation position must meet the required lengths of upstream and downstream straight pipe sections. Usually, the upstream straight pipe section should be at least 10 times the pipe diameter, and the downstream at least 5 times the pipe diameter. If there are flow-disturbing components such as pumps or valves upstream, the straight pipe section needs to be further extended.
| Upstream Flow-Disturbing Component | Minimum Upstream Straight Pipe Section | Minimum Downstream Straight Pipe Section |
|---|---|---|
| 90° elbow | 10D | 5D |
| Gradual expansion pipe | 15D | 5D |
| Valve | 20D | 5D |
Note: D is the inner diameter of the pipe.
Sensor Installation Orientation
Horizontal Pipes
On horizontal pipes, the sensor should be installed near the horizontal centerline of the pipe, avoiding installation at the top (prone to bubble accumulation) and bottom (prone to sediment deposition). It is usually recommended to install it on the side of the pipe, within a 45° angle from the horizontal plane.
Vertical Pipes
Vertical pipes are an ideal choice, as upward fluid flow can avoid bubble retention. The sensor can be installed at any position along the pipe circumference, but it is necessary to ensure that the clamp is tightened and the sensor is well coupled with the pipe wall.
Determining Sensor Spacing
The sensor spacing of the Prosonic flowmeter depends on the pipe size, material, and sensor model. Before installation, the spacing must be calculated according to the manual or determined using special tools. Incorrect spacing will result in weak signals or measurement failure.
- Confirm the outer diameter and wall thickness of the pipe.
- Consult the spacing table according to the sensor model.
- Use a tape measure or positioning tape to mark the sensor positions.
- Ensure that the axes of the two sensors are parallel and in the same plane.
Common Installation Errors and How to Avoid Them
- Error 1: Installation near pipe welds or flanges. Avoid welds by at least 2 times the pipe diameter.
- Error 2: Sensor misalignment. Use couplant and adjust until the signal is strongest.
- Error 3: Insufficient straight pipe section. Be sure to select the installation point according to the table above.
Correctly selecting the installation position is the key to successful Prosonic clamp-on installation. The next part will introduce the steps for fixing and commissioning the clamp.