1, working principle

KF series pneumatic base type instrument adopts modular structure and consists of a dozen standard function parts. Combining some of them can form various specifications of products. Pressure-KFP (fixed range), KFK (adjustable range); Temperature-KFT (fixed range); Differential pressure-KFD (adjustable range); Level-KFL (fixed range, adjustable proportion) Product Series. Divided from the function of the indicator regulator, indicating transmitter and indicator transmission regulator. Its regulation control method adopts the most mature PID regulation law at present.

As can be seen from the figure, the measurement unit converts the controlled parameters such as temperature and pressure into displacement signals and sends them to the indicating mechanism. The indicating mechanism changes the displacement signal into the indicator rotation angle and displays the measured value, and at the same time, the displacement signal is sent to the deviation mechanism of the regulator. The deviation mechanism compares this displacement with the displacement given by the given mechanism and outputs a difference displacement to the adjustment mechanism. This difference displacement is called the deviation displacement. The adjustment mechanism will shift this deviation and send it to the gas signal according to the PID adjustment law and send it. To adjust the valve, change the amount of air intake, make the measured parameters change, and finally control at a given value. This is the signal conversion and signal transmission process of the KF series meters.

2, the characteristics of pneumatic base type instrument

At present, there are many types of instruments used for industrial process control. The mainstream is an intelligent instrument that uses microprocessors for detection and control. However, according to the environmental characteristics of the leaching plant of the oil plant, a large amount of solvent is used, and it is not appropriate to use excessive electrical signals for control. In addition, in order to achieve multi-point tour inspection and computer control, a central control room and staff skilled in computer operation are required. Since the oil industry in our country has started late in the automatic control production, the development is slow, and there are lack of basic facilities and management operations. Needs a gradual process. Pneumatic base meter can solve the above problems.

This is directly installed on the production site, integrating detection, transmission, display and control, without having to introduce signals into the main control room. This instrument is compressed air as the power source, with safety explosion-proof (factory and analysis of explosion-proof electrical appliances factory) performance, simple structure, easy installation and maintenance, dustproof, waterproof, cold, free from electromagnetic interference, high reliability, Cheap and other advantages. And its parameter setting is easy to adjust, and the on-site staff is easy to master. Although the accuracy is not very high, the adjustment of the process parameters for the leaching workshop is sufficient. Therefore, the KF series pneumatic base type instrument is economical and practical.

3, application effect

In the oil industry, there are many places that need to be adjusted and controlled. The stability of various parameters in the production process is a prerequisite for ensuring product quality and reducing consumption. However, the current control method is very primitive. It is only at the entrance and exit of the equipment that the valves and indicator instruments are installed, which are manually adjusted by the on-site staff to achieve the purpose of control. In the process of continuous operation of the equipment, the material flow rate is not constant, and the pressure of the boiler is also randomly changed. This requires the operator to observe the instrument and adjust the valve anytime, anywhere. This control method is inefficient and has a large error. It is difficult to ensure that the equipment is in an optimal state of operation and that energy saving and consumption reduction cannot be achieved. In the oil plant leaching workshop, the use of steam heating equipment can be seen everywhere, the use of KF series pneumatic base type instrument is easy to install, but also can make up for the lack of manual operation. Taking the temperature control of the oil-rich heater in the tail gas paraffin recovery system as an example, if the temperature of the heater is too high, the paraffin oil will volatilize above its boiling point, resulting in the paraffin oil entering the water separator and the leacher. The consumption is too large; conversely, if the temperature of the heater is too low, the temperature of the rich oil will be reduced, and the analytical effect of the analytical tower will be poor, resulting in a decrease in the absorption efficiency of the absorption tower and a corresponding increase in the solvent consumption. It is difficult to control the temperature stability due to manual operation, resulting in the waste of paraffin waste gas recovery equipment of some companies, resulting in great waste. After installing the KFT type temperature control table, the temperature of the paraffin oil was effectively controlled with an error range of ±1, which not only ensured the technological effect but also reduced the solubility. In oil refinery leaching workshops, there are many similar control points. The control parameters are not just temperature. KFP pressure regulators, KFL liquid level regulators and other automatic control instruments have been gradually installed to achieve automation of the production process. Improve production efficiency and product quality. In order to change the backwardness of the oil industry, it has played a significant role in catching up with the advanced world level.