Patent Publication Number: US-2023143795-A1

Title: Recirculation of wet abrasive material in abrasive waterjet systems and related technology

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a division of U.S. patent application Ser. No. 15/839,708 filed Dec. 12, 2017 and issued as U.S. patent Ser. No. ______, which claims the benefit of U.S. Provisional Patent Application No. 62/433,167, filed Dec. 12, 2016, both applications are incorporated by reference herein in their entirety. To the extent the foregoing application and/or any other materials incorporated herein by reference conflict with the present disclosure, the present disclosure controls. 
    
    
     TECHNICAL FIELD 
     The present technology is related to abrasive waterjet systems. 
     BACKGROUND 
     Abrasive waterjet systems are used in precision cutting, shaping, carving, reaming, and other material processing applications. During operation of an abrasive waterjet system, a cutting head directs a high-velocity jet of liquid carrying particles of abrasive material toward a workpiece to rapidly erode portions of the workpiece. Abrasive waterjet processing has significant advantages over other material processing technologies (e.g., grinding, plasma-cutting, etc.). For example, abrasive waterjet systems tend produce relatively fine and clean cuts without heat-affected zones around the cuts. Abrasive waterjet systems also tend to be highly versatile with respect to the material type of the workpiece. The range of materials that can be processed using abrasive waterjet systems includes very soft materials (e.g., rubber, foam, leather, and paper) as well as very hard materials (e.g., stone, ceramic, and hardened metal). Furthermore, in many cases, abrasive waterjet systems are capable of executing demanding material processing operations while generating little or no dust, smoke, or other potentially toxic airborne byproducts. 
     Conventionally, abrasive material is passed through a cutting head of an abrasive waterjet system only one time and then discarded. This practice is wasteful because some abrasive material is still usable after one pass through a cutting head. For example, some abrasive material incorporated into a jet may be carried by a portion of the jet that does not contact a workpiece being processed. Wasting abrasive material is especially problematic when the abrasive material is used to process workpieces containing hazardous material (e.g., lead, beryllium copper, etc.). In these cases, disposal costs may approach or exceed material costs. Accordingly, there is a need for innovation in the field of abrasive material utilization in abrasive waterjet processing, such as to reduce or eliminate waste of abrasive material and/or to reduce or eliminate unduly high disposal costs. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1 A  is a cross-sectional side view of portions of an abrasive waterjet system in accordance with an embodiment of the present technology. 
         FIG.  1 B  is an enlarged view of a portion of  FIG.  1 A . 
         FIG.  2    is a flow chart illustrating a method for operating an abrasive waterjet system in accordance with an embodiment of the present technology. 
     
    
    
     DETAILED DESCRIPTION 
     Consumers generally recognize that abrasive waterjet processing is superior to other material processing technologies with respect to performance and versatility, but many consumers perceive abrasive waterjet processing to be relatively high cost. Indeed, the capital cost of an abrasive waterjet system suitable for heavy industrial use is relatively high. This is partially due to the relationship between operating pressure and abrasive material consumption in the field of abrasive waterjet processing. By far the greatest contributor to the operating cost of an abrasive waterjet system is the cost of abrasive material. Conventionally, increasing the operating pressure of an abrasive waterjet system was known to increase the abrasive material utilization efficiency of the system. This is because higher pressures enable greater acceleration of abrasive material entrained in a jet. Accordingly, a given amount of abrasive material carried by a jet generated from higher pressure liquid does more work than the same amount of abrasive material carried by a jet generated from lower pressure liquid. Also, a jet generated from higher pressure liquid typically moves laterally through a process recipe at a faster rate than a less powerful jet generated from lower pressure liquid. This faster lateral movement leads to more of the jet diameter (and more of the entrained abrasive material) striking a workpiece rather than passing into a catcher unused. 
     For the foregoing and other reasons, abrasive waterjet systems that operate at ultrahigh pressures (e.g., pressures of 50,000 psi or greater) are favored for most heavy industrial applications even though these systems tend to be more capital intensive than abrasive waterjet systems that operate at lower pressures. This is not necessarily the case, however, for hobbyist and light industrial applications. In these applications, consumers are often willing to sacrifice high abrasive material utilization efficiency and other advantages of ultrahigh pressure abrasive waterjet systems in order to reduce capital costs. There is a need, therefore, to mitigate the disadvantages of relatively low pressure abrasive waterjet systems to better serve these consumers. At least some embodiments of the present technology address this need and/or offer other advantages over conventional technologies. 
     Abrasive waterjet systems in accordance with at least some embodiments of the present technology include features that increase abrasive material utilization efficiency by allowing for recirculation of wet abrasive material. For example, an abrasive waterjet system in accordance with a particular embodiment includes a cutting head, a catcher, and a conveyance that carries slurry including abrasive material and liquid from the catcher toward the cutting head for reuse. As the abrasive material is recirculated multiple times, the fraction of pulverized abrasive material in the slurry slowly increases, eventually causing the cutting power of a batch of abrasive material to be effectively exhausted. At this point, the abrasive material can be swapped for fresh abrasive material and the recirculation can resume until the new abrasive material becomes exhausted. This approach not only dramatically improves abrasive material utilization, it allows an abrasive waterjet system to be more compact because the catcher can act as an abrasive material hopper taking the place of a separate hopper configured to handle dry abrasive material. For example, fresh abrasive material can simply be poured into the catcher continuously or in batches. Other advantages over conventional counterparts in addition to or instead of the foregoing advantages also may be present. Furthermore, as described below, abrasive waterjet systems and related devices, systems, and methods in accordance with embodiments of the present technology can have features in addition to or instead of features associated with recirculation of wet abrasive material. 
     Specific details of abrasive waterjet systems and related devices, systems, and methods in accordance with several embodiments of the present technology are disclosed herein with reference to  FIGS.  1 A- 2   . Although the systems, devices, and methods may be disclosed herein primarily or entirely with respect to hobbyist and light industrial abrasive waterjet applications, other applications in addition to those disclosed herein are within the scope of the present technology. Furthermore, it should be understood, in general, that other systems, devices, and methods in addition to those disclosed herein are within the scope of the present technology. For example, systems, devices, and methods in accordance with embodiments of the present technology can have different and/or additional configurations, components, and procedures than those disclosed herein. Moreover, a person of ordinary skill in the art will understand that systems, devices, and methods in accordance with embodiments of the present technology can be without one or more of the configurations, components, and/or procedures disclosed herein without deviating from the present technology. Abrasive waterjet systems in accordance with embodiments of the present technology can be used with a variety of suitable fluids, such as water, aqueous solutions, hydrocarbons, glycols, and nitrogen. As such, although the term “waterjet” is used herein for ease of reference, unless the context clearly indicates otherwise, the term refers to a jet formed by any suitable fluid, and is not limited exclusively to water or aqueous solutions. 
       FIG.  1 A  is a cross-sectional side view of portions of a waterjet system  100  in accordance with an embodiment of the present technology.  FIG.  1 B  is an enlarged view of a portion of  FIG.  1 A . With reference to  FIGS.  1 A and  1 B  together, the waterjet system  100  can include a pump  102  (shown schematically) configured to pressurize liquid  103  to a suitable pressure for a material processing application. In some cases, the pump  102  operates at relatively low pressure. For example, the pump  102  can have a maximum operating pressure of at most 15,000 psi, which is below the maximum operating pressure of most abrasive waterjet systems used in heavy industry. In other cases, the pump  102  can have a higher maximum operating pressure (e.g., within a range from 15,000 psi to 120,000 psi or greater). It should be noted, in general, that wet abrasive material recycling in accordance with embodiments of the present technology is potentially useful both in the context of abrasive waterjet systems that operate at relatively low pressure and in the context of abrasive waterjet systems that operate at relatively high pressure. For example, when a high-pressure abrasive waterjet system is used to process workpieces containing hazardous material, abrasive material utilization efficiency may be high, but high disposal costs may still warrant use of wet abrasive material recycling. Moreover, even when abrasive material utilization efficiency is high and disposal costs are low, wet abrasive material recycling may be beneficial to reduce the overall environmental impact of a process, to reduce abrasive material storage and handling requirements, and/or for other reasons. 
     With reference again to  FIGS.  1 A and  1 B , the waterjet system  100  can include a cutting head  104  downstream from the pump  102 . The cutting head  104  can include a jet-forming orifice  106  that receives pressurized liquid  103  from the pump  102 . The pump  102  can provide all or most of a total supply of liquid  103  to the jet-forming orifice  106 . The jet-forming orifice  106  can be defined by a jewel  108  held within a mount  110  disposed within the cutting head  104 . During operation of the waterjet system  100 , pressurized liquid  103  flowing through the jet-forming orifice  106  forms a jet  112 . Downstream from the jet-forming orifice  106 , the cutting head  104  can include a mixing chamber  114 . The cutting head  104  can also include a slurry inlet  116  through which the mixing chamber  114  receives slurry  117  including abrasive material  118  and liquid  103 . After exiting the mount  110 , the jet  112  passes through the mixing chamber  114 . Within the mixing chamber  114 , the jet  112  contacts slurry  117 , thereby causing abrasive material  118  to become entrained in the jet  112 . 
     As shown in  FIG.  1 A , the waterjet system  100  can further include a catcher  120  downstream from the cutting head  104 . The catcher  120  can contain a pool of liquid  103  that receives and disperses the jet  112 . After exiting the cutting head  104 , and before reaching the pool of liquid  103 , the jet  112  can contact a workpiece  122  supported by slats  123  near an uppermost portion of the pool of liquid  103 . After passing through the workpiece  122 , the jet  112  can carry kerf material  124  liberated from the workpiece  122 , spent (e.g., pulverized) abrasive material  118 , and unspent abrasive material  118  into the pool of liquid  103 . The catcher  120  can include an upper portion  126 , a lower portion  128 , and a screen  130  therebetween. Kerf material  124 , spent abrasive material  118 , and unspent abrasive material  118  from the jet  112  can settle by gravity from the upper portion  126  of the catcher  120  toward the lower portion  128  of the catcher  120 . 
     The screen  130  can be configured to restrict settling of large particles of kerf material  124  such that the large particles of kerf material  124  collect at the upper surface of the screen  130 . The screen  130  can be configured to lift out of the catcher  120  to facilitate occasional removal of the collected kerf material  124  from the catcher  120 . Screening and removing the large particles of kerf material  124  can reduce or eliminate the possibility of such particles recirculated into the cutting head  104  and thereby causing a clog or otherwise interfering with the coherency of the jet  112 . In at least some cases, energy from the jet  112  causes turbulence within the pool of liquid  103  below the workpiece  122 , which facilitates movement of abrasive material  118  and small particles of kerf material  124  toward the lower portion  128  of the catcher  120  via the screen  130 . In addition or alternatively, the catcher  120  can include one or more other components (e.g., a stirrer, a scraper, a recirculating pump, etc.; not shown) that promote this and/or other desirable movement of abrasive material  118  and small particles of kerf material  124  within the catcher  120 . 
     Below the screen  130 , the lower portion  128  of the catcher  120  can have a transverse cross-sectional area that decreases at successively lower elevations. For example, the lower portion  128  of the catcher  120  can be conical (as illustrated), slanted, trough shaped, etc. The shape of the lower portion  128  of the catcher  120  can be one that encourages abrasive material  118  within the catcher  120  to collect at a lowermost portion of the catcher  120 . The waterjet system  100  can include a fluidizer  132  coupled to the lower portion  128  of the catcher  120  where the abrasive material  118  collects. In at least some cases, the fluidizer  132  includes a slurry port  136  and a manifold  138  extending at least partially around a perimeter of the slurry port  136 . The waterjet system  100  can also include a conveyance  139  including a conduit  140  extending between the upper portion  126  of the catcher  120  and the manifold  138 . The fluidizer  132  can be configured to inject liquid  103  from the conveyance  139  into collected abrasive material  118  within the catcher  120  via the manifold  138 , thereby fluidizing abrasive material  118  at a region  142  above the manifold  138 . The conveyance  139  can also include a pump  144  disposed along the conduit  140 . The pump  144  can be configured to drive recirculation of liquid  103  through the conduit  140 , the manifold  138 , the lower portion  128  of the catcher  120 , and the upper portion  126  of the catcher  120  in series. Excess liquid  103  and floating fines can flow out of the catcher  120  to a drain (not shown) via an overflow port  145  at the upper portion  126  of the catcher  120 . 
     Fluidized abrasive material  118  at the region  142  above the manifold  138  can form slurry  117 . The waterjet system  100  can include a conveyance  146  including a conduit  147  extending between the fluidizer  132  and the cutting head  104  configured to receive the resulting slurry  117  from the catcher  120  via the slurry port  136 . In the illustrated embodiment, the conveyance  146  includes a holding tank  148  (shown schematically) disposed along the conduit  147 , and the conveyance  146  is configured to carry the received slurry  117  toward the holding tank  148 . The holding tank  148  can be useful to stage slurry  117  near the cutting head  104  and/or to attenuate fluctuations in demand for slurry  117  from the cutting head  104  relative to a supply of slurry  117  from the catcher  120 . Slurry  117  from the holding tank  148  (or directly from the conduit  147 ) can flow into the mixing chamber  114  via the slurry inlet  116 . In other embodiments, the holding tank  148  can be absent and the conduit  147  can be configured to deliver slurry  117  to the cutting head  104  directly. When present, the holding tank  148  can have a component (e.g., a stirrer, a recirculating pump, etc.; not shown) configured to agitate staged slurry  117  such that the staged slurry  117  is maintained in a flowable state. 
     In at least some cases, the waterjet system  100  includes a metering device  150  (e.g., a valve or orifice; shown schematically) configured to regulate the flow of slurry  117  into the mixing chamber  114 . Furthermore, the waterjet system  100  can include a detector  152  (also shown schematically) coupled to the metering device  150  (as illustrated) or separate from the metering device  150 . The detector  152  can be configured to detect a concentration of abrasive material  118  in slurry  117  flowing toward the mixing chamber  114 , such as by use of a turbidity sensor and/or a mass-flow sensor. In addition or alternatively, the detector  152  can be configured to detect a flowrate of slurry  117  flowing toward the mixing chamber  114 , such as by use of a rotameter and/or an ultrasonic sensor. As shown in  FIG.  1 A , the conveyance  146  can include a pump  154  disposed along the conduit  147 . The pump  154  can be configured to drive movement of slurry  117  from the catcher  120  toward the holding tank  148 . The cutting head  104  can be configured to draw slurry  117  from the holding tank  148  or from another portion of the conveyance  146  toward the mixing chamber  114  at least partially by the Venturi effect. As mentioned above, slurry  117  within the mixing chamber  114  can be entrained in the jet  112  and can be carried by the jet  112  back into the catcher  120 , thereby completing a pass through a recycling loop. 
     As the abrasive material  118  is recycled, the proportion of both kerf fines and fragmented abrasive fines in the slurry  117  may increase. A relatively high concentration of fines in the slurry  117  may interfere with the flowability of the slurry  117 . Accordingly, it may be useful to remove fines from the slurry  117  during operation of the waterjet system  100 . As shown in  FIG.  1 A , the waterjet system  100  can include a fines separator  156  (shown schematically) operably associated with the conveyance  146 . The fines separator  156 , for example, can be located along the conduit  147  between the pump  154  and the holding tank  148 . The waterjet system  100  can further include a conduit  158  configured to carry fines from the fines separator  156  toward a waste receptacle  160 . The fines separator  156  can include a hydrocyclone, a screen, or another suitable mechanism configured to separate fines from a remainder of the slurry  117 . Within the waste receptacle  160 , the fines can accumulate in a pile  162  for eventual disposal. Separation of fines from the slurry  117  at the fines separator  156  can occur batchwise or continuously. In some embodiments, the fines separator  156  and the holding tank  148  are combined rather than separate. In still other embodiments, the fines separator  156  can be eliminated. For example, when the abrasive material  118  is changed frequently, removing fines may be unnecessary to maintain suitable flowability of the slurry  117 . 
     With reference again to  FIGS.  1 A and  1 B , the waterjet system  100  can be configured for substantially closed-loop recycling of abrasive material  118 . For example, between batchwise change outs of abrasive material  118  within the waterjet system  100 , at least 90% of all abrasive material  118  within the waterjet system  100  can recirculate continuously through a recycling loop including the catcher  120 , the fluidizer  132 , the conveyance  146 , the cutting head  104 , and the jet  112 . During this recirculation, the fraction of spent abrasive material  118  within the waterjet system  100  can increase gradually as more and more unspent abrasive material  118  contacts the workpiece  122 . Spent abrasive material  118  and small particles of kerf material  124  that pass through the screen  130  can be carried with remaining unspent abrasive material  118  in the slurry  117  flowing through the recycling loop. Even when the smallest fraction of the spent abrasive material  118  and liberated kerf material  124  is removed at the fines separator  156 , the concentration of these material within the slurry  117  may steadily increase. Eventually, as the total solids content of the slurry  117  flowing through the recycling loop becomes dominated by spent abrasive material  118  and small particles of kerf material  124 , the cutting power of the jet  112  may diminish to an unacceptably low level. At this point, a batchwise changing of abrasive material  118  within the waterjet system  100  can be performed to restore the cutting power of the jet  112  to an acceptable level. Alternatively or in addition, recirculating abrasive material  118  can be removed and/or fresh abrasive material  118  can be added continuously or semi-continuously. 
     When the jet  112  is inactive (e.g., during repositioning of the cutting head  104 , during shutdown periods, and during workpiece placement) and at other times, it may be useful to at least partially clear the conveyance  146 , the metering device  150 , the fines separator  156 , and the cutting head  104  of abrasive material  118 . For example, when slurry  117  within these components is stagnant, it may tend to dewater and harden. The residual abrasive material  118  may then become non-flowable, leading to flow-passage restriction, clogging, or other problems when flow of slurry  117  resumes. In at least some cases, the waterjet system  100  is configured to at least partially clear components of the waterjet system  100  that carry the slurry  117  of the abrasive material  118  by increasing the flowrate of liquid  103  through the fluidizer  132 . When the flowrate of liquid  103  through the fluidizer  132  is relatively low, the liquid  103  may form the slurry  117  with a suitable concentration of abrasive material  118  for flowability through the conveyance  146  and for enhancing the cutting power of the jet  112 . Increasing the flowrate of liquid  103  through the fluidizer  132  may lower the concentration of abrasive material  118  within the slurry  117 . 
     At a certain point, increasing the flowrate of liquid  103  through the fluidizer  132  may cause the liquid  103  to be drawn through the slurry port  136  with little or no abrasive material  118  from the lower portion  128  of the catcher  120 . In this state, the liquid  103  may at least partially replace the slurry  117  within components of the waterjet system  100  downstream from the fluidizer  132 , thus at least partially clearing these components of abrasive material  118 . Operation of the jet  112  may continue during this process. Thereafter, the jet  112  and the fluidizer  132  may be turned off, and the conveyance  146  may continue to hold a static volume of the liquid  103 . Due to the relatively low concentration of abrasive material  118  within the liquid  103 , the components of the waterjet system  100  holding the liquid  103  may remain partially or entirely free of non-flowable abrasive material  118  until flow of slurry  117  through the conveyance  146  resumes. Accordingly, the fluidizer  132  can be useful not only to control the flowability of abrasive material  118 , but also to reduce or eliminate undesirable accumulation of abrasive material  118  when the jet  112  is inactive. 
     The waterjet system  100  can further include a controller  164  including a processor  166  and memory  168 . The controller  164  can be programmed with instructions (e.g., non-transitory instructions contained on the memory  168  and/or on a separate computer-readable medium) that, when executed, control operation of the waterjet system  100 . The controller  164  can be operably connected to the pumps  144 ,  154 , the metering device  150 , and the fines separator  156  via communication links  170 . The communication links  170  can be separate or combined, and can have any suitable form. For example, the communication links  170  can include any suitable wired and/or wireless communication components, such as wires and transceivers (e.g., antennas, Wi-Fi access points, Bluetooth transceivers, nearfield communication devices, wireless modems, etc.). In some cases, the controller  164  is local. In other cases, the controller  164  is remote. Furthermore, communication between the controller  164  and other components of the waterjet system  100  can be direct or indirect (e.g., via the Internet and/or via an intermediate computing system). 
       FIG.  2    is a flow chart illustrating a method  200  for operating the waterjet system  100  in accordance with an embodiment of the present technology. With reference to  FIGS.  1 A- 2    together, suitable operations of the method  200  can be effected via the controller  164 . The method  200  can include supplying pressurized liquid  103  to the jet-forming orifice  106  (block  202 ), and supplying slurry  117  to the mixing chamber  114  (block  204 ). Supplying pressurized liquid  103  can include supplying all or most of a total supply of pressurized liquid  103  to the jet-forming orifice  106  at a relatively low pressure (e.g., a pressure of at most 15,000 psi). Alternatively, the pressurized liquid  103  can be supplied at a higher pressure (e.g., within a range from 15,000 psi to 120,000 psi or greater). The method  200  can further include forming the jet  112  from the supplied pressurized liquid  103  at the jet-forming orifice  106  (block  206 ), and passing the jet  112  through the mixing chamber  114  while the mixing chamber  114  contains slurry  117  (block  208 ). This can cause abrasive material  118  from slurry  117  within the mixing chamber  114  to become entrained in the jet  112 . The jet  112  carrying entrained abrasive material  118  can then be impacted against the workpiece  122  to alter (e.g., cut) the workpiece  122  (block  210 ). After passing through the workpiece  122 , the jet  112  can be diffused in the catcher  120  (block  212 ). Abrasive material  118  carried by the jet  112  can then settle within the lower portion  128  of the catcher  120  by gravity (block  214 ). In conjunction with this settling, the method  200  can include screening large particles of kerf material  124  from abrasive material  118  within the catcher  120  (block  216 ). 
     At a high level, the method  200  can include recycling abrasive material  118  through a substantially closed-loop circuit including the mixing chamber  114 , the catcher  120 , and the conveyance  146 . For example, the method  200  can include flowing at least 90% by weight of abrasive material  118  in a batch of fresh abrasive material  118  through this loop at least twice. Accumulated (e.g., settled) abrasive material  118  within the catcher  120  can be converted into slurry  117  to facilitate flowability. For example, the method  200  can include flowing liquid  103  or other fluidizing liquid from the upper portion  126  of the catcher  120  to the lower portion  128  of the catcher  120  via the manifold  138  to fluidize accumulated abrasive material  118  within the catcher  120  and thereby convert the accumulated abrasive material  118  into slurry  117  (block  218 ). The method  200  can further include collecting slurry  117  from the catcher  120  via the slurry port  136  (block  220 ) and removing fines from collected slurry  117  at the fines separator  156 , such as by operation of a hydrocyclone (block  222 ). Next, the method  200  can include flowing (e.g., by pumping and/or by the Venturi effect) collected slurry  117  into the mixing chamber  114  via the conveyance  146 , the fines separator  156 , the metering device  150 , and the slurry inlet  116  (block  224 ). 
     The method  200  can also include detecting a concentration of abrasive material  118  in collected slurry  117  (block  226 ), and automatically adjusting a flowrate of slurry  117  flowing into the mixing chamber  114  at least partially in response the detected concentration (block  228 ). This can be useful, for example, to reduce variation in a flowrate of abrasive material  118  into the mixing chamber  114 , and corresponding variation in a cutting power of the jet  112 . Furthermore, as discussed above, the cutting power of the jet  112  can decrease steadily as the fraction of spent abrasive material  118  and kerf material  124  in slurry  117  recirculating through the waterjet system  100  increases. In at least some cases, the method  200  includes automatically detecting a decreased cutting power of the jet  112  (block  230 ). The method  200  can also include automatically decreasing a rate of movement of the cutting head  104  through a predetermined sequence of movements (e.g., a process recipe) at least partially in response to the detected and/or an expected decreased cutting power of the jet  112 . Similarly, the method  200  can include automatically adjusting a rate of movement of the cutting head  104  through a predetermined sequence of movements at least partially in response a detected and/or an expected concentration of abrasive material  118  in slurry  117  recirculating through the waterjet system  100 . These adjustments can be useful, for example, to mitigate any adverse effect of changes in the quality or quantity of abrasive material  118  over time on the performance (e.g., accuracy, efficiency, etc.) of software that controls movement of the cutting head  104 . 
     The method  200  can include increasing a flowrate of fluidizing liquid flowing toward abrasive material  118  at the fluidizer  132  to flush the conveyance  146  with fluidizing liquid (block  232 ). This can be useful, for example, to reduce or eliminate abrasive material  118  from the conveyance  146  in preparation for discontinuing flow through the conveyance  146 . When the conveyance  146  is filled with fluidizing liquid, or at another suitable time, the method  200  can include ceasing forming the jet  112  (block  234 ). In some cases, this occurs when the cutting power of the jet  112  becomes or is expected to be unacceptably low. For example, this can be after a predetermined time following a batchwise changing of abrasive material  118  within the waterjet system  100  and/or at least partially in response to a detected and/or expected decrease in the cutting power of the jet  112 . In other cases, ceasing forming the jet  112  may be associated with maintenance or loading of the waterjet system  100 , or other circumstances. 
     While the jet  112  is ceased, spent abrasive material  118  can be removed from the catcher  120  (block  236 ) and fresh abrasive material  118  can be added to the catcher  120  (block  238 ). Next, the method  200  can include recharging the conveyance  146  with slurry  117  including fluidized abrasive material  118  from the catcher  120  (block  240 ) in preparation for resuming a cutting operation. In some cases, the fluidizer  132  is shut off after the conveyance  146  is flushed with fluidizing liquid. In these cases, recharging the conveyance  146  can include restarting the fluidizer  132  and resuming forming the jet  112 . The cutting head  104  can then draw slurry  117  into the conveyance  146  such that the slurry  117  replaces the fluidizing liquid held in the conveyance  146  while the jet  112  was inactive. In other cases, the fluidizer  132  remain in operation while the jet  112  was inactive. With reference again to  FIGS.  1  and  2   , the method  200  can include resuming a cutting operation (block  242 ) after the conveyance  146  is recharged with slurry  117 . When a process recipe is resumed, a rate at which the cutting head  104  moves according to the process recipe can be greater than it was when the process recipe was paused to account for an increase in the cutting power of the jet  112  due to the presence of fresh abrasive material  118 . Alternatively or in addition, recirculating abrasive material  118  can be removed and/or fresh abrasive material  118  can be added continuously or semi-continuously. Furthermore, flushing the conveyance  146  with fluidizing liquid and then recharging the conveyance  146  with slurry  117  can occur in conjunction with an interruption in operation of the jet  112  not associated with changing or supplementing the abrasive material  118 . 
     This disclosure is not intended to be exhaustive or to limit the present technology to the precise forms disclosed herein. Although specific embodiments are disclosed herein for illustrative purposes, various equivalent modifications are possible without deviating from the present technology, as those of ordinary skill in the relevant art will recognize. In some cases, well-known structures and functions have not been shown and/or described in detail to avoid unnecessarily obscuring the description of the embodiments of the present technology. Although steps of methods may be presented herein in a particular order, in alternative embodiments the steps may have another suitable order. Similarly, certain aspects of the present technology disclosed in the context of particular embodiments can be combined or eliminated in other embodiments. Furthermore, while advantages associated with certain embodiments may have been disclosed in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages or other advantages disclosed herein to fall within the scope of the present technology. 
     Certain aspects of the present technology may take the form of computer-executable instructions, including routines executed by the controller  164 . In some embodiments, the controller  164  is specifically programmed, configured, or constructed to perform one or more of these computer-executable instructions. Furthermore, some aspects of the present technology may take the form of data (e.g., non-transitory data) stored on the memory  168  or stored or distributed on other computer-readable media, including magnetic or optically readable or removable computer discs as well as media distributed electronically over networks. Accordingly, data structures and transmissions of data particular to aspects of the present technology are encompassed within the scope of the present technology. The present technology also encompasses methods of both programming computer-readable media to perform particular steps and executing the steps. 
     Throughout this disclosure, the singular terms “a,” “an,” and “the” include plural referents unless the context clearly indicates otherwise. Similarly, unless the word “or” is expressly limited to mean only a single item exclusive from the other items in reference to a list of two or more items, then the use of “or” in such a list is to be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of the items in the list. Additionally, the terms “comprising” and the like may be used herein to mean including at least the recited feature(s) such that any greater number of the same feature(s) and/or one or more additional types of features are not precluded. Directional terms, such as “upper,” “lower,” “front,” “back,” “vertical,” and “horizontal,” may be used herein to express and clarify the relationship between various elements. It should be understood that such terms do not denote absolute orientation. Reference herein to “one embodiment,” “an embodiment,” or similar formulations means that a particular feature, structure, operation, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present technology. Thus, the appearances of such phrases or formulations herein are not all referring to the same embodiment. Furthermore, various particular features, structures, operations, or characteristics may be combined in any suitable manner in one or more embodiments of the present technology.