阅读说明：本技术 一种液相色谱仪恒流泵的自动校准装置及工作方法 (Automatic calibration device for constant flow pump of liquid chromatograph and working method ) 是由 黄磊 陈浩飞 李娟� 于 2020-11-20 设计创作，主要内容包括：本发明涉及一种液相色谱仪恒流泵的自动校准装置,包括精密电子天平、压力传感器、恒流泵、色谱工作站的电脑控制端和测试液储液瓶,所述精密电子天平、压力传感器以及恒流泵均通过通讯总线与电脑控制端相连,所述恒流泵通过流动相输入管与测试液储液瓶连接,所述压力传感器通过管路与负载连接,进行流量校准时,所述恒流泵通过管路与精密电子天平连接；进行压力校准时,所述恒流泵通过管路与压力传感器连接。本发明还提供了上述自动校准装置的工作方法。本发明实现了流量校准,压力校准,动态探漏和静态探漏四个过程校准的自动化和标准化,在产品的批量生产中,大大提高了生产效率,而且也保证了产品各个参数性能的一致性。(The invention relates to an automatic calibration device of a constant flow pump of a liquid chromatograph, which comprises a precision electronic balance, a pressure sensor, a constant flow pump, a computer control end of a chromatographic workstation and a test solution storage bottle, wherein the precision electronic balance, the pressure sensor and the constant flow pump are all connected with the computer control end through a communication bus; when pressure calibration is carried out, the constant flow pump is connected with the pressure sensor through a pipeline. The invention also provides a working method of the automatic calibration device. The invention realizes the automation and standardization of the calibration in the four processes of flow calibration, pressure calibration, dynamic leakage detection and static leakage detection, greatly improves the production efficiency in the mass production of products, and ensures the consistency of the performance of each parameter of the products.)

1. The utility model provides an automatic calibration device of liquid chromatograph constant flow pump which characterized in that:

comprises a precision electronic balance, a pressure sensor, a constant flow pump, a computer control end of a chromatographic workstation and a test solution storage bottle,

the precision electronic balance, the pressure sensor and the constant flow pump are all connected with the computer control end of the chromatographic workstation through a communication bus, the constant flow pump is connected with the test solution storage bottle through a mobile phase input tube, the pressure sensor is connected with a load through a pipeline,

when the flow is calibrated, the constant flow pump is connected with a precision electronic balance through a pipeline; when pressure calibration is carried out, the constant flow pump is connected with the pressure sensor through a pipeline.

2. The automatic calibration device for a constant flow pump of a liquid chromatograph according to claim 1, wherein:

the communication bus is an RS485 cable.

3. The automatic calibration device for a constant flow pump of a liquid chromatograph according to claim 1, wherein:

the load is a spent chromatographic column.

4. The working method of the automatic calibration device of the liquid chromatograph constant flow pump is characterized by comprising four processes of flow calibration, pressure calibration, dynamic leakage detection and static leakage detection:

the flow calibration process comprises the steps that a constant flow pump flow Q1 is arranged at a computer control end, liquid is pumped into a test liquid storage bottle on a precision electronic balance for T minutes continuously, the liquid mass M and the liquid mass M in the precision electronic balance are read from the computer control end and converted into the volume V corresponding to the liquid, the actual flow Q2 of the constant flow pump in the T minutes is calculated, then an instruction is sent by the computer control end, the actual flow Q2 is transmitted to the constant flow pump, and the constant flow pump is controlled to finish automatic flow calibration;

the pressure calibration process comprises the steps that a load is connected, the constant flow pump is slowly started by the computer control end, the flow rate of the constant flow pump is increased or decreased, the actual pressure value of the constant flow pump reaches a plurality of selected preset pressure values, when the constant flow pump reaches the preset pressure values, the computer control end reads and records the AD value of the constant flow pump and the actual pressure value of the pressure sensor, according to the AD value of the constant flow pump at each selected point and the actual pressure value of the pressure sensor, the computer control end calculates a curve equation and sends the curve equation to the constant flow pump to be stored, and pressure calibration is completed;

the dynamic leak detection process comprises the steps that a load is connected, the flow of a constant flow pump is set by a computer control end to gradually and slowly increase from zero, the pressure of the pump is gradually increased, and finally when the pressure is increased to 42Mpa, the pressure is kept unchanged, if no leakage occurs within several minutes, the dynamic leak detection is finished, if the pressure is not removed for a long time within a period of time, the leakage situation possibly occurs, the computer control end gives out warning that the leak detection is unqualified, and the operation is repeated until the leak detection passes;

the static leakage detection process comprises the steps that the computer control end plugs a liquid path outlet of the constant flow pump by a choke plug, the constant flow pump is started to slowly increase and adjust the flow of the pump from 0, when the pressure of the pump reaches 42Mpa, the pump is stopped and is kept for 5 minutes, and if the pressure of the pump is not less than 40Mpa after being attenuated, the pump is qualified.

5. The operating method of the automatic calibration device for the constant flow pump of the liquid chromatograph according to claim 4, wherein:

in the pressure calibration process, the selected predetermined pressure values include 0Mpa, 0.1Mpa, 0.5Mpa, 1Mpa, 10Mpa and 20 Mpa.

6. The operating method of the automatic calibration device for the constant flow pump of the liquid chromatograph according to claim 4, wherein:

and in the flow calibration process, the pumping time of the constant flow pump is at least 5 minutes.

Technical Field

The invention relates to calibration control of a constant flow pump of a liquid chromatograph, in particular to an automatic calibration device and a working method of the constant flow pump of the liquid chromatograph, and belongs to the technical field of production inspection of the constant flow pump of the liquid chromatograph.

Background

The high-pressure constant flow pump is a very important component in the liquid chromatograph, is used as a liquid infusion unit in the liquid chromatographic system, provides stable and balanced flow phase flow for the whole chromatographic system, and ensures the stable operation of the system. The common structure of the constant flow pump of the liquid chromatograph is a reciprocating constant flow pump, and each parameter index of the pump needs to be checked during assembly and production, and the common structure mainly comprises flow calibration, pressure calibration, dynamic leakage detection and static leakage detection, and the specific process is as follows:

and (4) flow calibration, namely, the flow set by the constant flow pump of the liquid chromatograph corresponds to a fixed rotating speed. The flow accuracy is generally determined by taking a fixed time (5 minutes or more), collecting the liquid (mostly pure water) flowing out of the constant flow pump, and accurately weighing the liquid by a balance. The liquid mass is converted into a corresponding volume, the flow value of the constant flow pump is calculated, then the deviation between the actual flow and the set flow is calibrated, and relevant parameters are manually input into the instrument and stored.

Pressure calibration: load (generally, a proper waste chromatographic column can be selected) and an external pressure gauge are connected, the flow of the pump is manually adjusted, and different pressures can be generated at different flows. Common pressure points that need calibration are: 0MPa, 0.1MPa, 0.5MPa, 1MPa, 10MPa and 20 MPa. And recording pressure gauge values corresponding to the pressure points and AD values of the pressure sensors, calculating a pressure curve equation, and manually inputting and storing relevant parameters into the instrument.

Dynamic leakage detection: after the load is connected, the pump flow is set to gradually and slowly increase from zero, the pump pressure can also be gradually increased, at the moment, whether liquid leaks from joints of all pipelines can be observed, if liquid leaks, the pumps are stopped and timely checked and fastened again, the pumps are started again, the operation is repeated, when the pressure is increased to 42Mpa, the situation that no liquid leaks can be maintained for a plurality of minutes is shown, the dynamic leakage detection is finished, and at the moment, the pumps can be stopped.

Static leak detection: the computer control end plugs the outlet of the liquid path of the constant flow pump by a choke plug, the pump is started, the flow of the pump is slowly increased from 0 to adjust, and the pump is stopped when the pressure of the pump reaches 42 Mpa. And (4) continuing for 5 minutes after stopping the pump, and ensuring that the pump pressure is attenuated within a certain range, namely the pump pressure is qualified when being more than 40 Mpa.

In the prior art, the four steps need repeated operation of personnel, and for the mass production of products, the consistency of the product performance is difficult to realize due to large workload of manual operation, and the production efficiency is also influenced.

Disclosure of Invention

The invention aims to provide an automatic calibration device for a constant flow pump of a liquid chromatograph, which can realize automatic inspection and calibration of each parameter of the constant flow pump and realize consistency of product performance.

In order to solve the problems, the technical scheme adopted by the invention is as follows:

an automatic calibration device of a liquid chromatograph constant flow pump comprises a precision electronic balance, a pressure sensor, a constant flow pump, a computer control end of a chromatographic workstation and a test solution storage bottle,

the precision electronic balance, the pressure sensor and the constant flow pump are all connected with the computer control end of the chromatographic workstation through a communication bus, the constant flow pump is connected with the test solution storage bottle through a mobile phase input tube, the pressure sensor is connected with a load through a pipeline,

when the flow is calibrated, the constant flow pump is connected with a precision electronic balance through a pipeline; when pressure calibration is carried out, the constant flow pump is connected with the pressure sensor through a pipeline.

Further, the communication bus is an RS485 cable.

Further, the load is selected from a waste chromatographic column.

The invention also provides a working method of the automatic calibration device of the constant flow pump of the liquid chromatograph, which comprises four processes of flow calibration, pressure calibration, dynamic leakage detection and static leakage detection:

the flow calibration process comprises the steps that a constant flow pump flow Q1 is arranged at a computer control end, liquid is pumped into a test liquid storage bottle on a precision electronic balance for T minutes continuously, the liquid mass M and the liquid mass M in the precision electronic balance are read from the computer control end and converted into the volume V corresponding to the liquid, the actual flow Q2 of the constant flow pump in the T minutes is calculated, then an instruction is sent by the computer control end, the actual flow Q2 is transmitted to the constant flow pump, and the constant flow pump is controlled to finish automatic flow calibration;

the pressure calibration process comprises the steps that a load is connected, the constant flow pump is slowly started by the computer control end, the flow rate of the constant flow pump is increased or decreased, the actual pressure value of the constant flow pump reaches a plurality of selected preset pressure values, when the constant flow pump reaches the preset pressure values, the computer control end reads and records the AD value of the constant flow pump and the actual pressure value of the pressure sensor, according to the AD value of the constant flow pump at each selected point and the actual pressure value of the pressure sensor, the computer control end calculates a curve equation and sends the curve equation to the constant flow pump to be stored, and pressure calibration is completed;

the dynamic leak detection process comprises the steps that a load is connected, the flow of a constant flow pump is set by a computer control end to gradually and slowly increase from zero, the pressure of the pump is gradually increased, and finally when the pressure is increased to 42Mpa, the pressure is kept unchanged, if no leakage occurs within several minutes, the dynamic leak detection is finished, if the pressure is not removed for a long time within a period of time, the leakage situation possibly occurs, the computer control end gives out warning that the leak detection is unqualified, and the operation is repeated until the leak detection passes;

the static leakage detection process comprises the steps that the computer control end plugs a liquid path outlet of the constant flow pump by a choke plug, the constant flow pump is started to slowly increase and adjust the flow of the pump from 0, when the pressure of the pump reaches 42Mpa, the pump is stopped and is kept for 5 minutes, and if the pressure of the pump is not less than 40Mpa after being attenuated, the pump is qualified.

Further, in the pressure calibration process, the selected predetermined pressure values include 0Mpa, 0.1Mpa, 0.5Mpa, 1Mpa, 10Mpa and 20 Mpa.

Further, in the flow calibration process, the pumping time of the constant flow pump is at least 5 minutes.

The principle of the invention lies in that each parameter index of the constant flow pump is observed through a computer control end. After the automatic calibration is finished, whether the calibration result passes or not is judged, and if the calibration result does not pass, the problem needs to be checked until the automatic calibration passes.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the connection of the precision electronic balance, the pressure sensor and the constant flow pump is controlled in real time through the computer control end, so that manual operation is greatly reduced, automatic calibration in four processes of flow calibration, pressure calibration, dynamic leakage detection and static leakage detection is realized, the automation and standardization of calibration are achieved, the production efficiency is greatly improved in the mass production of products, and the consistency of various parameter performances of the products is also ensured.

Drawings

Fig. 1 is a schematic structural diagram of an automatic calibration device for a constant flow pump of a liquid chromatograph according to the present invention during flow calibration.

Fig. 2 is a schematic structural diagram of the automatic calibration device for the constant flow pump of the liquid chromatograph for pressure calibration according to the present invention.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples. The objects, aspects and advantages of the present invention will become more apparent from the following description. It should be understood that the described embodiments are preferred embodiments of the invention, and not all embodiments.

Referring to fig. 1 and 2, an automatic calibration device for a constant flow pump of a liquid chromatograph includes a precision electronic balance 1, a pressure sensor 2, a constant flow pump 3, a computer control terminal 4-1 of a chromatographic workstation 4, and a test solution storage bottle 5. The precise electronic balance 1, the pressure sensor 2 and the constant flow pump 3 are all connected with a computer control end 4-1 of the chromatographic workstation 4 through a communication bus 6, the constant flow pump 3 is connected with a test solution storage bottle 5 through a mobile phase input pipe 9, the pressure sensor 2 is connected with a load 8 through a pipeline 7, and the load 8 can be selected from proper waste chromatographic columns. When flow calibration is carried out, the constant flow pump 3 is connected with the precision electronic balance 1 through a pipeline 7; when pressure calibration is performed, the constant flow pump 3 is connected with the pressure sensor 2 through a pipeline. The communication bus 6 is preferably an RS485 cable.

The invention also provides a working method of the automatic calibration device of the constant flow pump of the liquid chromatograph, which comprises four processes of flow calibration, pressure calibration, dynamic leakage detection and static leakage detection:

the flow calibration process comprises the steps that a constant flow pump flow Q1 is arranged at a computer control end 4-1, liquid is pumped into a test liquid storage bottle 5 on a precision electronic balance 1 for 5 minutes continuously, the liquid mass M and the liquid mass M in the precision electronic balance 1 are read from the computer control end 4-1 and converted into the volume V corresponding to the liquid, the actual flow Q2 of the constant flow pump 3 in T minutes is calculated, then an instruction is sent by the computer control end, the actual flow Q2 is transmitted to the constant flow pump 3, and the constant flow pump 3 is controlled to finish automatic flow calibration;

the pressure calibration process comprises the steps of connecting the load 8, slowly starting the constant flow pump 3 by the computer control end 4-1, increasing or reducing the flow speed of the constant flow pump 3, and enabling the actual pressure value of the constant flow pump to reach a plurality of selected preset pressure values, wherein the selected common preset pressure values comprise 0Mpa, 0.1Mpa, 0.5Mpa, 1Mpa, 10Mpa and 20 Mpa. When the constant flow pump 3 reaches a preset pressure value, the computer control end 4-1 reads and records the AD value of the constant flow pump and the actual pressure value of the pressure sensor 2, and according to the AD value of the constant flow pump at each selected point and the actual pressure value of the pressure sensor 2, the computer control end 4-1 calculates a curve equation and sends the curve equation to the constant flow pump 3 for storage, so that pressure calibration is completed;

the dynamic leak detection process comprises the steps that a load 8 is connected, the flow of a constant-flow pump is gradually and slowly increased from zero through a computer control end 4-1, the pressure of the pump is gradually increased, and finally when the pressure is increased to 42Mpa, the pressure is kept unchanged, if no liquid leakage occurs within minutes, the dynamic leak detection is finished, if the pressure is not removed for a long time within a period of time, the liquid leakage situation possibly occurs, the computer control end gives an alarm that the leak detection is not qualified, and the operation is repeated until the leak detection passes;

the static leakage detection process comprises the steps that the computer control end 4-1 plugs the liquid path outlet of the constant flow pump 3 by a choke plug, the constant flow pump 3 is started to slowly increase from 0 to adjust the pump flow, when the pump pressure reaches 42Mpa, the pump is stopped and is kept for 5 minutes, and if the pump pressure is not less than 40Mpa after being attenuated, the pump is qualified.

According to the invention, the connection of the precision electronic balance, the pressure sensor and the constant flow pump is controlled in real time through the computer control end, so that manual operation is greatly reduced, automatic calibration in four processes of flow calibration, pressure calibration, dynamic leakage detection and static leakage detection is realized, the automation and standardization of calibration are achieved, the production efficiency is greatly improved in the mass production of products, and the consistency of various parameter performances of the products is also ensured.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not intended to limit the scope of the present invention, and it is obvious that any person skilled in the art can easily conceive of alternative or modified embodiments based on the above embodiments and these should be covered by the present invention.