Study On Precise Feed System Of Abrasive For Micro Abrasive Water Jet

Micro abrasive water jet is a new micro processing technology based on the traditional abrasive water jet machining technology. It has many advantages, such as the unique soft and cold cutting manner, no heat affected zone, good surface quality, no sparks, no pollution and energy concentration. It is mainly used in hard and brittle materials processing and the area of micro-etching.The feed system of traditional abrasive water jet is reviewed. Because of the shortcoming of micro abrasive water jet feed system, a new system named precise feed system of abrasive for micro abrasive water jet based on the principle of screw conveyor is put forward.The structure of screw feed system for micro abrasive water jet is introduced in detail. The composition of system, the principle of screw conveyor, the choice of screw parameters and the relation equation between abrasive flow rate and geometric parameters of screw were discussed. At last, a precise feed system of abrasive for micro abrasive water jet is manufactured. The system is controlled by PMAC and L298. It has solved the questions such as low energy density, poor continuity, easy clogging and other issues existed in traditional feed system for abrasive water jet.The flow rate equation in the screw is derived. The simulation is finished based on Fluent. It was showed that angular speed is a key factor to the abrasive feeding. In the parameters of screw, the depth has stronger affection to flow rate than the width. Although the cross area get larger by increasing the depth of screw, the flow rate becomes smaller.The milling experiment using micro abrasive water jet verified that abrasive flow rate can be control accurately by screw speed. The precise feed system of abrasive for micro abrasive water jet could meet the requirements in use.The precise feed system of abrasive for micro abrasive water jet has the advantages of accurate stability, flow rate adjustable and non-blocking characteristics. It is economy and reliability. It has a high practical value and good promising in application.