Fork Level Switch to Measure Flowing Liquids in Vertical Pipelines

This article introduces a practical solution for the application of two innovative methods of Fork Level Switch for measuring flowing liquids in vertical pipelines.

Difficulties in Liquid Level Measurement of Vertical Pipelines

1.      Fast liquid velocity, high pressure in the vertical pipes, high impaction of the flow;

2.      Liquid in vertical pipelines often enters intermittently, with many bubbles and foams;

3.      Narrow space around the pipeline limits the installation position and the method of measuring sensor;

4.      Requires high response of the level switch

Method I

A water storage tank is equipped laterally. To ensure the water enter into water storage tank, a welded water diversion plate is also equipped. A return tube is opened at the lower part of the water storage tank to facilitate the water return to vertical pipe. The diameter of the return tube is d, the size should be determined based on the size of water storage tank, so that when water enters the water storage tank, it can quickly dip to the tines; when no water in the pipe, the water in water storage tank can quickly return to the vertical pipe, so that the liquid level of the water storage tank and the vertical pipe is basically the same.

Method II

The vertical pipe leads out a side pipe with a matching flange of the sensor. The sensor is also equipped with U-groove as the sketch. The radius of U-groove is about 20 mm with thickness of 1 mm. It is cut by a round tube and welded on the flange of sensor. The total length of U-groove should be longer than the tines’ length. The length of extension part L1 is about 10 mm, and the end of U-groove should extend into the vertical pipe as L2. The length of L2 is about 10 ~ 20 mm, and the plugging height at the end of U-groove is aligned with the lower part of tines. The specific size of the U-groove should be determined by the size of the pipe as well as the installation position, and the opening of the U-groove should face up to the flow direction.

The design principle is to make the baffle at the end of U-shaped groove blocks the liquid in U-groove. When liquid flows down the vertical pipe, it rises the liquid level in U-groove and immerses the tines, so the sensor sends out an alarm signal. When no liquid flows down the vertical pipe, the liquid is blocked by the baffle, so the tines will not immersed by liquid.

Advantages of Ring-11 Liquid Level Switch

On basis of the high requirements for liquid level measuring instruments to the working conditions of vertical pipeline, Ring-11 Liquid Level Switch is the ideal choice.

Ring-11 Liquid Level Switch is a high reliability control switch specially used for liquid level measurements. The excellent, stable and reliable performance and quality are comparable to imported peers.

Based on the fork resonant principle, when a fork vibrates in harmonic resonance comes in contact with measured liquid, its vibrating frequency will greatly decrease. The fork’s harmonic resonant frequency has been precisely pre-adjusted to achieve high sensitivity so the lowest measurable density can be as low as 0.5g/cm³, and can withstand the pressure of 64bar. Jiwei Ring-11 liquid level switch is excellent in level measurement for acids like HCL, H₂SO₄, H₂SO₃, and alkali liquids, syrup, medical liquids, industrial wastewater, etc. And particularly, it is suitable for pressured liquefied gas (such as LNG) and applications under complicated working conditions where measured liquid is easy to foaming, bubbling or with high viscosity and under vibration disturbance environment etc.

Ring-11 Liquid Level Switch has passed SIL2 / SIL3 Functional Safety Assessment, as well as certified for both Intrinsic Safety and Flameproof Enclosure explosion protection. Four optional outputs: relay output, two-wire system, NAMUR and transistor.