The phrase "orifice tube" refers to a small tube or opening that is present in some systems, such as air conditioning or fuel systems. It helps control the flow of fluids, allowing them to pass through at a specific rate. Full definition
OTs are most likely out of the question here (yes, modern systems, especially ones featuring variable compressors, are pretty always based on a TXV, because orifice tubes are obsolete technology that can't allow for any superheat adjustment. (mechanics.stackexchange.com)
Includes A / C Compressor and Clutch, A / C Accumulator, A / C Orifice Tube, A / C Compressor Oil Additive, A / C Service Valve Cap, A / C System Flush, A / C System Seal Kit, A / C System Valve Core and Cap Kit (carparts.com)
During the recharge pressures should be noted, and ensure that the drier and the orifice tube are servicible. (mechanics.stackexchange.com)