Design of Protective Baffle for Level Switches

For lateral installation, to prevent the probe from direct impact damage by falling materials and prevent material build-up, it is recommended to install approx.20°inclined to the vessel bottom, and install a protection baffle above the probe.

Protective baffle is a kind of thick stainless-steel or iron plate that is installed above the instrument probe in a certain shape to prevent the probe from being directly impacted by falling materials, so as to extend the service life, as well as to avoid false alarms.

Depending on different applications, contact level switches (such as vibrating rod level switch, tuning fork level switch, rotary paddle switch, RF admittance level switch, etc.) can be installed from above, lateral and the bottom, or used as high/low-level alarms. For lateral installation, to prevent the probe from direct impact damage by falling materials and prevent material build-up, it is recommended to install approx.20°inclined to the vessel bottom, and install a protection baffle above the probe.

Based on different characteristics of materials (material roughness, particle size, medium hardness), the shapes of protective baffle are various, such as upward V-shape, downward V-shape, circular arc shape, flat plate, etc. In practical applications, upward and downward V-shape protective baffles have better effects on protection.

To protect the probe from direct impact damage, a protection baffle should be installed above the vibrating body, and longer than intrusion depth (horizontal). Generally, a protection baffle can be a convex shape (inverted “V” section) . If the medium is coarse and abrasive, baffle in concave shape (erected “v” section) , so the medium could stack up a bit in concave area.

Upward V-shaped protective baffle

Upward V-shaped protective baffle known as concave protective baffle. The materials accumulate in the groove to form the impaction and abrasion, so as to reduce the impaction on protective baffle. The positive V-shaped protective baffles are mainly applicable to the materials with rough surface, high hardness, strong impaction (such as small gravel, glass slag and small steel slag). Shown as "b" in the figure.

Downward V-shaped protective baffle

Downward V-shaped protective baffle is also called convex protective baffle. When materials fall above, they slide down from both sides of the plates, so direct impaction avoids triggering on the probe. Due to the long-term direct impaction, downward V-shaped protective baffles are only suitable for mediums with low wear, low hardness, low density and smooth surfaces, such as powder, rice, fly ash, etc. Shown as "a" in the figure. #levelswitch #levelmeasurement

Due to the long-term directly impaction, downward V-shaped protective baffles are only suitable for mediums with low wear, low hardness, low density and smooth surfaces, such as powder, rice, fly ash, etc. Shown as "a" in the figure.

The positive V-shaped protective baffles are mainly applicable to the materials with rough surface, high hardness, strong impaction (such as small gravel, glass slag and small steel slag). Shown as "b" in the figure.