Composition of loading system

Oil tanker loading: the material to be loaded can be kerosene, naphtha, gasoline, LPG, and so on. The pump used by the tanker is centrifugal pump, which is driven by a motor. Relevant loading arms pertaining to these oils are equipped. The loading monitoring and management system is located in the loading monitoring room in railway loading site.

Ration loading monitoring and management system consists of flow meter, ration loading controller, Pneumatic two -piece O-ring ball valve (digital control valve), anti-static grounding switch, anti-overflow switch as well as monitoring and control station.

Mass flow meter is used for flow rate measurement at loading arm position. Measurement accuracy can be divided into two categories: 0.2% and 0.5%, which depends on the type of oil to be loaded. Power supply will be 220VAC/50Hz. Output will be pulse. Class of explosive-proof: ExdIIBT4. The power supply of the mass flow-meter will be provided by ration loading controller. The output of it is used by ration loading controller.

Pneumatic two-stage O-ring ball valve or digital control valve will be used for loading control.

Pneumatic plunger-type two-piece O-ring trip valve is a type of valve that can perform two times open and two times close operation. It is one of pneumatic ball valve. Only two solenoid valves are applied within actuator control loop, which makes the design for control section very simple and excellent switching performance can be expected from two-piece ball valve. The structure of this type of valve determines the liquid inside the valve change smoothly during period of switching, so explosion and damage to the flow-meter and pressure meter can be prevented.

When digital valve and ration controller are used together, flow-rate can be controlled accurately. Initiating with small

flow-rate, being controlled with high flow-rate, and being closed with small flow-rate. Through keeping constant flow-rate under different pipe pressure, very high measurement accuracy can be expected. Digital control valve usually

is equipped with external pilot valve control loop which is composed of normal-open solenoid valve, normal-close

solenoid valve, filter and open/close speed control component.

Realization of loading system and its function

Ration loading controller receives flow-rate signal produced by mass flow-meter and send out open/close order to two-piece ball valve (digital control valve), at the same time, it receives contact signal from antistatic grounding switch and anti-overflow switch to guarantee the safety during loading operation. Field ration loading controller utilizes redundant communication to relay these signal to the host computer inside the control room,

Ration loading controller can display information such as state of field valve and grounding switch and malfunction state in the form of Chinese pattern. It also can perform valve configuration and adept local and remote operation mode. It can record over 1000 pieces of operation data. It boasts data protection function in case of power being cut off and redundant RS-485 communication interface.

You can use monitoring system of host computer to operate and monitor process flow, to monitor equipment status, to monitor and verify equipment failure, to create graphical dynamic display, to produce invoices and print them, to save data, to set technological parameter as well as to print failure and production report.