Research On High Speed And Anti-clogging Spray Marking System

As an actuator for marking defects,the spray marker is widely used in automated nondestructive testing equipment.The spray guns currently in use have problems such as slow response,easy clogging,and easy wear of the spray needle;in the high-speed detection process,there are also phenomena such as inaccurate marking and missing marking.For this reason,this paper proposes and studies a high-speed,anti-blocking spray mark device and spray mark system to effectively solve above problems.In order to obtain a faster dynamic response speed,the currently used pneumatic spray gun structure is changed to an electric actuator,and the current single valve control is changed to a three-valve sequential control in spray marking system.Combined with the steel pipe nondestructive testing equipment,a control strategy to ensure the mark circumferential and axial accuracy under the spiral of the steel pipe is studied.With the STM32F429 chip as the core,the controller hardware circuit design and the Sys Tick precise timing program design are completed.A ZCD brass solenoid switch valve was selected.Based on the coil excitation current detection,the dynamic characteristics of the solenoid valve were tested.The influence of the structural parameters of the components of the applicator-nozzle,air cap,gun body on the atomization effect and flow rate are analyzed,and the design of the applicator is improved according to the degree of influence of different parameters.The sprayer was produced,and a series of tests on the atomization performance of the sprayer under the control of three valves,the relationship between the paint pressure,the nozzle opening time and the flow rate,the relationship between distance from the nozzle height to the steel pipe surface and the spray point size,and the anti-blocking effect were carried out.And the spray mark accuracy experiment was carried out,defect positioning error and its cause were analyzed.Finally,the method of multi-color marking is proposed,the arrangement scheme and control strategy of multi-color spray markers with double-row axial array are designed,and the multi-color spray marking system including mechanical,pneumatic hydraulic and control system is designed.The application verifies the effectiveness of the classification marking of the multi-color spray marking system.