2020.02.04
Summary:Filling system in the weighing process to provide fast and slow two-stage feeding, its fast and slow feeding material flow can be individually adjusted, so as to ensure that to meet the accuracy requirements of measurement and speed requirements. The automatic control of the cement filling machine is realized through PLC, and the practical cement batching and mixing control scheme based on S7-300PLC, TP27-10 touch screen, load cell, etc., is used to dynamically detect and control the production site and realize production automation.
In recent years, with the development of offshore oil exploration and development business, the development of the sea area is gradually extended from the shallow sea to the deep sea, and the conduit racks and platform blocks are also developed in the direction of high, large and heavy. The demand for mud required for offshore piling is also increasing, and the mud quality requirement is also improving. Weighing and filling machine adopts PLC to control the mud production process, which can realize the full automation of the production process and improve the production efficiency. Weighing and filling machine control system consists of two parts: field control and PLC control. Field control mainly consists of a variety of transfer switches, buttons, relays and contactors, etc.; PLC control system in addition to a variety of motors, solenoid valves, in addition to automatic control functions, but also for the production of parameter settings, dynamic display of the operating state of various equipment in the production process, the realization of raw materials, weighing display, fault alarms, etc. The entire system includes cement silo feeding, horizontal screw transmission, vertical screw transmission, The whole system includes cement silo feeding, horizontal screw transmission, vertical screw transmission, additive feeding, water feeding, raw material buffer device, raw material weighing device, stirrer, mixer, slurry output device, control system and pneumatic parts.
1 Programmable controller and human-machine interface part
The control core is composed of Siemens S7-312 CPU and digital input module, analog input module and digital output module. It completes the switch input, data detection, calculation and process control, realizes the full-automatic control of the mud production process and the dynamic monitoring of various equipment operating conditions. The man-machine interface adopts Siemens TP27-10 touch screen with RS485 communication interface. It also makes full use of various flexible commands of Siemens software to design a modular and structured program, which makes the program have good readability, portability and maintainability. At the same time, using the powerful communication protocol of Siemens PLC - MPI protocol, only one data line and software settings can realize the communication between touch screen and PLC. The monitoring software consists of three screens: main interface, weighing interface and operation interface. In the main interface, you can set production parameters, dynamically monitor the operation of various motors and solenoid valves, and issue alarms in case of incorrect operation. The operation screen allows the selection of manual or automatic control of various components. The weighing interface can pre-adjust the weighing parameters to reduce the weighing error and improve the measuring accuracy.
2 Transmission section
The transmission part includes horizontal screw conveyor, vertical screw conveyor, buffer tank, hopper scale, mixer, agitator and slurry pump. After the system is running, the horizontal screw and vertical screw will transfer the cement to the cement buffer tank, the water pump will send the outside fresh water to the water buffer tank, and the additive pump will transfer all kinds of additives to the additive buffer tank.PLC collects the data from the weighing module, and controls the corresponding action of the outlet valve of each buffer tank. Each hopper weighing amount reaches the pre-set value, measuring hopper outlet valve open, in the mixer mixing 45s later, open the slurry valve, mud into the mixer. The slurry is transported to the outside world through the slurry pump for on-site use. In order to make the cement mix evenly in the mixer and reduce dust, the program sets the fresh water in the water metering hopper to be discharged, and then opens the cement metering hopper outlet valve. Because cement is dusty particles that tend to stick together, a vibration diffuser is installed on the side wall of the cement metering hopper.
3 Data detection and control section
