Abrasive waterjets （AWJs） can be used in extreme mining conditions for hard rock destruction, due to their ability to effectively cut difficult-to-machine materials with an absence of dust formation. They can also b...Abrasive waterjets （AWJs） can be used in extreme mining conditions for hard rock destruction, due to their ability to effectively cut difficult-to-machine materials with an absence of dust formation. They can also be used for explosion, intrinsic, and fire safety. Every destructible material can be considered as either ductile or brittle in terms of its fracture mechanics. Thus, there is a need for a method to predict the efficiency of cutting with AWJs that is highly accurate irrespective of material. This problem can be solved using the energy conservation approach, which states the proportionality between the material removal volume and the kinetic energy of AWJs. This paper describes a method based on this approach, along with recommendations on reaching the most effective level of destruction. Recommendations are provided regarding rational ranges of values for the relation of abrasive flow rate to water flow rate, standoff distance, and size of abrasive particles. I also provide a parameter to establish the threshold conditions for a material＇s destruction initiation based on the temporary-structural approach of fracture mechanics.展开更多
The structure, working principles, and main technological parameters of the premajet derusting machine are introduced. Experiments were made to test the relationship among such jet parameters as working pressure, rate...The structure, working principles, and main technological parameters of the premajet derusting machine are introduced. Experiments were made to test the relationship among such jet parameters as working pressure, rate of water flow, abrasive weight consistency and derusting efficiency. Reasonable parameters were decided. Results prove that the derusting machine is characterized by its high derusting efficiency (as high as 20m 2/h), good derusting quality (as good as ISO8501 1 Sa 2.5), and low specific power consumption (about 0.3kW·h/m 2). Therefore it is a new type of high efficiency derusting machine.展开更多
文摘Abrasive waterjets （AWJs） can be used in extreme mining conditions for hard rock destruction, due to their ability to effectively cut difficult-to-machine materials with an absence of dust formation. They can also be used for explosion, intrinsic, and fire safety. Every destructible material can be considered as either ductile or brittle in terms of its fracture mechanics. Thus, there is a need for a method to predict the efficiency of cutting with AWJs that is highly accurate irrespective of material. This problem can be solved using the energy conservation approach, which states the proportionality between the material removal volume and the kinetic energy of AWJs. This paper describes a method based on this approach, along with recommendations on reaching the most effective level of destruction. Recommendations are provided regarding rational ranges of values for the relation of abrasive flow rate to water flow rate, standoff distance, and size of abrasive particles. I also provide a parameter to establish the threshold conditions for a material＇s destruction initiation based on the temporary-structural approach of fracture mechanics.
文摘The structure, working principles, and main technological parameters of the premajet derusting machine are introduced. Experiments were made to test the relationship among such jet parameters as working pressure, rate of water flow, abrasive weight consistency and derusting efficiency. Reasonable parameters were decided. Results prove that the derusting machine is characterized by its high derusting efficiency (as high as 20m 2/h), good derusting quality (as good as ISO8501 1 Sa 2.5), and low specific power consumption (about 0.3kW·h/m 2). Therefore it is a new type of high efficiency derusting machine.
