Ceramic Hybrid Bearings have Steel races and Ceramic Balls. Ceramic Balls are suitable for applications where high loads, high speeds and extreme temperatures are factors. Long life and the need for minimal lubrication make this material appropriate for extreme applications. Ceramic is non-porous, non-magnetic, non corrosive and lighter than steel. In ball form, ceramic balls are also harder than steel and because ceramic balls are non-porous they are virtually frictionless and capable of spinning faster than steel balls. Ceramic Bearings,Ceramic Ball Bearings,Hybrid Ceramic Bearing,Hybrid Ceramic Ball Bearings Ningbo Ritbearing Imp & Exp Co.,Ltd. , http://www.ritbearingchina.com
I. Daqing Petrochemical Company's gas metering status The majority of our company's gas measurement used the orifice plate as a measurement element in the past. The differential pressure transmitter was used as a meter and the signal was transmitted remotely. The orifice plate has insurmountable drawbacks: the range ratio is only 3:1, pressure loss is large, intermediate links are numerous, and maintenance is difficult. In addition, the flow rate measurement range of steam varies greatly depending on the season and operating conditions. Because there is no throttling flowmeter with wide-range technology, the phenomenon of over-measurement range is very common, resulting in a large measurement error.
In response to this situation, our company introduced FCI gas mass flowmeter in 2004. FCI can be used to measure gases such as superheated steam, saturated steam, and nitrogen. Its intelligent processor can realize data changes; automatic compensation of temperature and pressure and remote communication and other advantages.
Our company applied FCI to nitrogen gas metering and after nearly 5 years of operation, it has achieved good results. FCI's thermally diffusive sensing elements have proven to have unmatched performance and reliability in applications that combine demanding environments with stringent process control requirements.
II. APPLICATION OF FCI GAS FLOW METER IN NITROGEN GAS MEASUREMENT FCI's unique thermal diffusion technology provides superior accuracy and reliability as well as high repeatability indicators for flow, level/interface and temperature operation. Typical FCI sensing elements include two thermowell protected RTDs (Platinum RTDs). When the two RTDs are placed in a fluid, one of the RTDs is heated and the other is used to sense the process temperature. The temperature difference between two RTDs is related to the process flow rate and the nature of the process medium. Higher flow or denser media will accelerate the cooling of the heated RTD and accelerate the temperature difference between the two RTDs.
The temperature difference between the two RTDs reaches a maximum without flow. As the flow rate increases, the heated RTD cools and the temperature difference decreases. The change of fluid velocity directly affects the degree of thermal diffusion, and then affects the temperature difference between the two RTDs. An electronic control circuit can convert the temperature of the RTD into a DC voltage signal. These two signals are output at the output terminal and are used to drive two adjustable setpoint alarm lines. The two alarm lines can be individually set on-site based on flow, level/interface or temperature operation.
Because the relationship between flow and RTD cooling effects is directly related to mass flow measurement in gas applications, FCI thermal diffusion technology provides a highly repeatable, accurate gas or air mass flow measurement. The "intelligent" circuit equipped with advanced micro-processing circuits allows the user to easily set the signal output. At the same time, it can also use the built-in keypad or handheld communicator to perform on-site adjustment of the display or alarm.
1. The use of platinum RTD sensors at the reference end and mass balancers in mass flow meters balance the mass of the two RTDs, which means that sudden changes in temperature during use can also ensure accurate mass flow measurements.
2.FCI gas mass flow meter metal is wear-free, anti-corrosion, no regular use of gasoline, kerosene, alcohol, etc. to clean the flow element and the detection hole, it can ensure long-term stable operation of the sensor. FCI gas mass flowmeters, unlike vortex flowmeters, are susceptible to measurement accuracy when they are easily contaminated by media.
3. The range ratio can be as large as 1000:1.
4. The low pressure drop fluid regulator enables the FCI flow meter to be used even when the upstream and downstream straight pipe lengths are shorter than normal, and can guarantee accuracy, resulting in a pressure drop that is less than 1/3 of that of any other current rectifier.
5. Optional reverse flow detection to detect forward and reverse flow.
6. Multi-point or single-point measurement, multi-point and average techniques provide highly repeatable, highly accurate, and more cost-effective measurements. The single-point type is suitable for small-diameter flow measurement, and the multi-point type is suitable for applications where the lengths of large-diameter pipes, square pipes, and straight pipe sections cannot meet the requirements.
7. Intelligent design, simple operation interface and convenient configuration. Strong software features, self-diagnostic capabilities can prompt the instrument personnel to prompt the fault type and fault location.
8. The structure is simple, easy to install, electronic components can be disassembled and checked at will. The microprocessor is used as the core component of signal detection and processing, which can filter out the interference signal caused by vibration to the utmost and optimize the quality and quality of the signal.
In actual use, the FCI is compared with the original orifice differential pressure band temperature and pressure compensation measurement system:
First of all, FCI does not have a pressure guiding tube that is similar to an orifice plate. There is basically no leakage point and there is no need to worry about inaccurate measurement due to leakage.
Second, compared with other flow meters, the FCI gas mass flow meter's instrument maintenance is relatively small. Sewage pressure loss after installation, no potential leakage. In winter, there is no need for thermal insulation, and there is no need for rain protection in summer. Basically, it belongs to maintenance-free instrumentation equipment. At the same time, this instrument is installed online during installation and does not affect normal production.
Third, it is very important that the measurement accuracy is high and it is obviously better than the orifice plate. In March 2005, the two sets of different measurement data measured by the orifice plate measurement system and the gas mass flow meter were compared and analyzed. The data measured by the gas mass flow meter coincided with the actual delivery volume of the compressor, and the orifice plate measurement system measured There is a clear deviation between the data and the actual delivery volume of the compressor, and the deviation of the measurement data of the orifice plate measurement system is very obvious at small flow rates.
Third, the economic evaluation Since the company applied FCI gas mass flow meter, because its flow measurement is very accurate, solve the problem of measurement data fluctuations of the product gas, very popular with the company's measurement staff welcome.
Ceramic Balls are usually made of following materials:
Silicon Nitride (SiN4)
Alumina Oxide (Al2O3)
Zirconia Oxide (ZrO2)
Silicon Carbide (SiC)
Because ceramic is a glass like surface it has an extremely low coefficient of friction and is ideal for applications seeking to reduce friction. Ceramic balls require less lubrication and have a greater hardness than steel balls which will contribute to increased bearing life. Thermal properties are better than steel balls resulting in less heat generation at high speeds.
Introduction Due to the different characteristics of the production equipment and technology of the petrochemical enterprises, and the large temperature difference between the winter and the summer in our company's geographical location, the steam and nitrogen are greatly adjusted in actual production. In view of the above situation, it is particularly important to select the appropriate nitrogen measurement and detection equipment. In the last two or three years, our company introduced some new metering gas meters and used some new gas flow technologies. Among them, FCI gas mass flow meter is used as a new measurement technology application to measure product gas and achieve good results.