Development of CNC Oil Filling Network System

Development of measurement and equipment numerical control oil filling network system Chen Tangmin (Guangdong Light Industry Vocational and Technical College, Guangdong 510300) - 485 computer network, genie configuration software, ADAM-5000 series data collector and LCB-9800 with low pressure loss and wear resistance A series of stainless steel oval gear flowmeters are combined to form a CNC oil filling network system.

Quantity; K is the meter factor.

Due to the existence of the valve switching time, the barrel error is caused, the time for the CNC to issue the start command to the CNC to issue the switching command, t2 is the time when the CNC sends the switching command to the completion of the switching, and the flow rate Q1 can be approximated as the average flow rate Qi at the closing time t2. It can be expressed as two. Error analysis bookmark2 The traditional filling barrel type numerical control oil filling device adopts the A and B valve control modes in the control, that is, the A valve is opened when the oil filling starts, and the B valve is closed, when the liquid to be filled reaches the preset of the barrel. When the quantity is output, the command is issued, the A valve is closed, and the B valve is opened. When the liquid to be filled reaches the preset amount of the barrel, the command is issued, the B valve is closed, and the A valve is opened, and the process is repeated until the preset total is reached. The amount is up.

The volume V of the filling bucket is: the error formula of V is calculated by the Taylor series expansion method + "2t2) dF is the steady state of the output pulse of the flowmeter. It is caused by the qualitative and flow fluctuation of the 4!9800! series stainless steel oval gear flow Pu. The error vK1 dK is the error caused by the nonlinear error of the meter's meter coefficient, fdt is the false output pulse frequency caused by the digital signal counting error, and the relative error of the filling tank liquid volume is: poor, 2 core 2 is the closing time of the valve The resulting error; it can be seen that the accuracy of the volume of liquid filled into the barrel is not only related to the accuracy of the flow meter, but also related to the closing time of the control valve. Therefore, how to solve the error caused by the closing time of the A and B valves It is also a problem to be solved by the numerical control oil filling system. The relative error of the A valve control is Y=the time from the start of the A valve command to the numerical control to issue the switching command; the relative error of the B valve control is t"2 is the closing time of the B valve; "1 is the time when the CNC sends the start B valve command to the CNC to issue the switching command.

In the current work, in order to reduce the error caused by the valve closing time, it can be known from equation (2) that the error caused by the valve closing time can be compensated by adjusting the meter coefficient, that is, it is necessary to correct the closing time of the A and B valves. , that is, according to F2t'2=F3t"2 for calibration, the closing time of the A and B valves should be measured first.

Third, the system design of the actual instrument coefficient of the bookmark5 flow meter, Ft1K1 is the volume of the filling bucket preset by the numerical control device, F ((1++t2) K2 is the volume of the actual filling bucket, and Ft1K2 is the preset of the numerical control oil filling device The volume of the filling bucket is a constant; fFt2K2 is the compensation value of the error caused by the valve closing time, and t2K2 is a constant; the method considers that the flow rate is stable during the filling process, that is, F is a constant.

However, due to the actual work, the flow rate is changed. The 5000 series data collector and the LCB-9800 series stainless steel elliptical gear flowmeter with low pressure loss and wear resistance are combined to form a numerical control oil filling network system. The working principle is shown in the figure. . Because the RS-485 network is the most widely used bidirectional transmission standard in the industry, it has the characteristics of multiple stations, fast transmission speed, long transmission distance, and the system only needs a pair of completely isolated twisted pairs, which can greatly reduce Wiring materials, reducing the communication components (such as repeaters, filters, etc.) to simplify installation, saving network construction costs; ADAM ie +Ft2K2 is a variable; and A, B valves are often closed, so if The closing time of the A valve is adjusted according to the formula (4), which often causes the volume error of the filling tank controlled by the B valve to be too large. For example, the error caused by the difference between the closing time of the two valves A and B is V, and the V is the barrel. Volume, F3 is the B valve control flow corresponding flow meter output pulse frequency - for AA control flow corresponding flow meter PublishingHouse.Allrights / frequency channel, each channel has high and low limit alarm function, and has manual control start and stop function, It can be controlled independently from the computer and can exchange data with the host at any time. One ADAM5080D constitutes a set of dual gun control mechanism, one channel count The other channel measures the frequency and performs the valve closing time compensation. The GENIE3.0 configuration software is a Windows version of the measurement and control and development software, which has multiple functions such as data analysis and report output. Its features include: easy-to-operate interface Standard Visual Basic programming environment, and provides a variety of connection tools, including built-in DDE, automatic OLE and IPX network communication, embedded ODBC function can directly enter a wide range of databases from SQL; LCB-9800 series stainless steel oval gear flowmeter, It has corrosion resistance, high accuracy, low pressure loss, stable output pulse frequency, adjustable duty cycle, suitable for long-distance transmission, and can be widely used in small flow, low viscosity liquid, automatic control system, etc. The oil network system has the characteristics of simple structure, flexible expansion, high accuracy, good reliability and high efficiency, and can be widely applied.

IV. Conclusion - The 5000 series data collector and the LCB-9800 series stainless steel oval gear flowmeter with low pressure loss and strong wear resistance are combined to form a numerical control oil filling network system with simple structure, flexible expansion, high accuracy and good reliability. High efficiency, so it can be widely used in petroleum, chemical, pharmaceutical, light industry, food and other industries.

(Finish)

SDDF QE series pressure filters are designed in accordance with international regulation, which consist of a Filter Housing with a screw on cover plate.

Standard equipment

-mounting holes in the filter head

-two-piece bowl for size 660 and above

-compatibility with fire-resistant fluids HFA/HFC

-drain plug with pressure relief(size 330 and above)

Connection Diagram

DF QE connection