Select shopping cart. Guest shopping cart Existing cart. Silos for bulk solids Level measurement and point level detection in silos. Measuring task:. Application In the chemical industry, many different kinds of bulk solids are produced or used as raw materials. To ensure reliable measurement of silo contents, many factors must be considered: different bulk densities, abrasive properties, dust generation and the requirements of explosion protection.
Implementation of the most suitable level sensors ensures optimal production planning and reliable logistics for the finished products. Your benefit Reliable. Cost effective. VEGAPULS 69 Non-contact radar level measurement in bulk solids silos Reliable measurement even with large amounts of dust and filling noise Suitable even for high, narrow silos or segmented containers, thanks to good signal focusing Can be used in media of differing consistency and in different measuring ranges Simple installation and calibration, even on filled silos.
Measuring range - Distance. Process temperature. Process pressure. Show Product. VEGAVIB 63 Point level detection with vibrating level switches in bulk solids silos Universally applicable for all granulated bulk solids Wear and maintenance-free measurement Simple, adjustment-free setup and commissioning. Pitso Mmakola. Mohd Salah Ahmed. Hui Chen Janice. Tomson Stellus. Siti Amalina.
Show More. Views Total views. Actions Shares. No notes for slide. Level measuring instruments 1. Temperature Error Liquid inside the vessel is hotter than the liquid inside the gauge. Unequal heighted liquid columns balance each other, if filled with liquids of different densities 8. Floats — contd. Greater the vertical height of the fluid, greater the pressure A simple pressure gauge attached to the bottom of the vessel may be calibrated to indicate the level of liquid.
Differential pressure transmitters connected in this manner respond to an increased liquid level by driving their output signal high and vice versa for level indication in the vessel.
The weight of the displaced fluid is directly proportional to the volume of the displaced fluid if the surrounding fluid is of uniform density. The Buoyant Force Instrument The basic principle behind the capacitive level instruments is the capacitance eqn. Total views 24, On Slideshare 0. From embeds 0. Number of embeds If the ultrasonic transducer is rugged enough, and the process vessel sufficiently free of sludge and other sound-damping materials accumulating at the vessel bottom, the transducer may be mounted at the bottom of the vessel, bouncing sound waves off the liquid surface through the liquid itself rather than through the vapor space.
As stated previously, any significant difference in sonic velocity between the two materials is sufficient to reflect a sound wave. This arrangement makes fillage the natural measurement, and ullage a derived measurement calculated by subtraction from total vessel height. As mentioned previously, the calibration of an ultrasonic level transmitter depends on the speed of sound through the medium between the transducer and the interface.
For top-mounted transducers, this is the speed of sound through the air or vapor over the liquid, since this is the medium through which the incident and reflected wave travel time is measured. For bottom-mounted transducers, this is the speed of sound through the liquid. Ultrasonic level instruments enjoy the advantage of being able to measure the height of solid materials such as powders and grains stored in vessels, not just liquids.
Again, the fundamental criterion for detecting a level of material is that the speeds of sound through the upper and lower materials must differ the greater the difference, the stronger the echo.
A unique challenge to solids measurement is the distinct possibility of uneven material profiles. A classic problem encountered when measuring the level of a powdered or granular material in a vessel is the angle of repose formed by the material as a result of being fed into the vessel at one point:.
This angled surface is difficult for an ultrasonic device to detect because it tends to scatter the sound waves laterally instead of reflecting them strongly back toward the instrument.
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