Pressure Transducer Definition
Pressure transducers can be defined as a type of transducer which converts physical pressure into an electrical signal. They can be used for measuring pressure in liquids and gases. Pressure transmitter is another term commonly used for a Pressure Transducer and are suitable for a range of applications in different areas depending on their specifications.
Most pressure transducers use strain gauges which are bonded to the internal diaphragm of the transducer. As pressure is applied through the pressure port, the diaphragm will deflect which causes the strain gauges to compress, this alters the output signal. The deformation of the strain gauges is directly related to the force being applied enabling the high accuracy pressure transducer to give an accurate pressure reading.
How does a pressure transducer work ?
Pressure transducers are usually composed of pressure sensitive elements and signal processing units. According to different test pressure types, the smart pressure transducers can be divided into gauge pressure transducers, differential pressure transducers and absolute pressure transducers.
Based on the different measurements of the above three pressures, we have designed pressure transducers with different working principles:
1. Piezoresistive force transducer: The resistance strain gauge is one of the main components of the piezoresistive strain transducer. The working principle of the metal resistance strain gauge is the phenomenon that the resistance value changes with the mechanical deformation of the strain resistance adsorbed on the base material, commonly known as the resistance strain effect.
2. Ceramic pressure transducer: The ceramic pressure transducer is based on the piezoresistive effect. The pressure directly acts on the front surface of the ceramic diaphragm, causing the diaphragm to deform slightly. The thick film resistor is printed on the back of the ceramic diaphragm and connected to form a Wheatstone Bridge, due to the piezoresistive effect of the varistor, the bridge generates a highly linear voltage signal proportional to the pressure and proportional to the excitation voltage. The standard signal is calibrated to 2.0/3.0/3.3mV according to the different pressure ranges. /V, etc., compatible with strain gauge transducers.
3. Diffused silicon pressure transducer: The working principle of the diffused silicon pressure transducer is also based on the piezoresistive effect. Using the piezoresistive effect principle, the pressure of the measured medium directly acts on the diaphragm of the transducer (stainless steel or ceramics), so that the diaphragm is generated and the medium The micro-displacement proportional to the pressure changes the resistance value of the transducer, and the electronic circuit is used to detect this change and convert and output a standard measurement signal corresponding to this pressure.
4. Sapphire pressure transducer: Using the working principle of strain resistance, using silicon-sapphire as a semiconductor sensitive element, it has unparalleled measurement characteristics. Therefore, semiconductor sensitive components made of silicon-sapphire are not sensitive to temperature changes, and have good working characteristics even under high temperature conditions; sapphire has extremely strong radiation resistance; in addition, silicon-sapphire semiconductor sensitive components have no p-n drift.
5. Piezoelectric pressure transducer: Piezoelectric effect is the main working principle of piezoelectric transducer. Piezoelectric transducer cannot be used for static measurement, because the charge after external force is only saved when the loop has infinite input impedance. . This is not the case in reality, so this determines that the piezoelectric transducer can only measure dynamic stress.
More explain for pressure transducer working principle
Pressure Transducer Types
High accuracy pressure transducers are available as different types which are suitable to different applications and industries. The different types of pressure transducer which we have available are as follows:
Explosion proof pressure transducer – Intrinsically safe pressure transducer are for applications in high risk environments. We also have explosion proof pressure transducers for extremely hazardous environments.
Sanitary pressure transducer-It also called snap on pressure transducer, which combines proven thin film transducer technology with a sanitary isolation seal. It is essential in hygienic processing environments such as the food and pharmaceutical industries.
Diaphragm pressure transducer-A diaphragm pressure transducer is a mechanical device that converts pressure changes into an electric signal, which can be measured to gauge changes in pressure. Diaphragm pressure transducers are particularly useful for low pressure transducer applications.
Submersible Pressure Transducer – these are also known as liquid level meters and are used to measure the pressure in water tanks and other similar applications.
SIL-2 Pressure Transducer – these are for applications with a safety integrated performance level requirement.
Combined Pressure and Temperature Transducer – we also have a range of pressure transducers which are combined with temperature transducers. This allows the one transducer to take two measurements, perfect for applications in small spaces and well proven in Motorsports in particular.
Extrusion pressure transducer- It also called the high temperature high pressure transducer, which used to measure pressure along the extruder barrel and at the screen changer, melt pump, and extruder die.
General Pressure Transducer – we have a range of pressure transducers which includes various sizes and pressure ranges – see them all on our website.
Pressure Transducer Applications
As you can see from the above types of pressure transducers, they are very diverse and therefore can be found in almost any industry. They are used for such a wide variety of applications. Pressure transducers are mainly used in: booster cylinders, superchargers, gas-liquid booster cylinders, gas-liquid boosters, presses, compressors, air-conditioning refrigeration equipment and other fields.
1. Applied to hydraulic system
In the hydraulic system, the hydraulic pressure transducer is mainly used to complete the closed-loop control of the force. When the control spool moves suddenly, a peak pressure several times the working pressure of the system will be formed in a very short period of time. In typical mobile and industrial hydraulics, any oil pressure transducer can quickly be destroyed if not designed with such extreme conditions in mind. It is necessary to use a shock-resistant hydraulic transducer. There are two main methods for the pressure transducer to achieve shock resistance. One is to change the strain gauge chip, and the other is to connect an external coil. Generally, the first method is used in the hydraulic system, mainly because Easy to install. Another reason is that the pressure transducer is subject to constant pressure pulsations from the hydraulic pump.
2. Applied to safety control system
Pressure transducers are often used in safety control systems, mainly targeting the safety management system of the air compressor itself. There are many transducer applications in the field of safety control. As a very common transducer, it is not surprising that pressure transducers are used in safety control systems.
The application in the field of safety control is generally considered from the aspects of performance, from the consideration of price, and from the safety and convenience of actual operation. It has been proved that the effect of selecting a pressure transducer is very good. The pressure transducer uses the processing technology of mechanical equipment to install some components and signal conditioners on a small chip. So small size is also one of its advantages, in addition, cheap is another big advantage of it. To a certain extent, it can improve the accuracy of system testing. In the safety control system, the pressure brought by the compressor is controlled to a certain extent by installing a pressure transducer in the pipeline equipment at the air outlet. This is a certain protection measure and a very effective control system. When the compressor starts normally, if the pressure value does not reach the upper limit, the controller will open the air inlet and adjust the equipment to reach the maximum power.
3. Applied to injection mold
Pressure transducers play an important role in injection molds. The pressure transducer can be installed in the nozzle of the injection molding machine, the hot runner system, the cold runner system and the cavity of the mold. Plastic pressure somewhere between the cavities.
4. Applied to monitoring mine pressure
Transducer technology is one of the key technologies for mine pressure monitoring. On the one hand, we should correctly apply various existing transducers to serve the mining industry; on the other hand, as a transducer manufacturer, we must also develop and develop new pressure transducers to adapt to more mining industry applications. There are many kinds of pressure transducers, and based on the special environment of mine pressure monitoring, mine pressure transducers mainly include: vibrating wire pressure transducer, semiconductor piezoresistive pressure transducer, metal strain gauge pressure transducer, differential transformer pressure transducer, etc. These transducers have a wide range of applications in the mining industry, and the choice of which transducer to use depends on the specific mining environment.
5. Used in compressors, air conditioning and refrigeration equipment
Pressure transducers are often used in air compressors and air-conditioning refrigeration equipment. These transducer products are small in size, easy to install, and the pressure guide port generally adopts a special valve pin design.
