An ultrasonic flow meter device, comprising: a piping arrangement (601,650) comprising a tubular body (602,651) extending along a longitudinal axis from a first end to a second end and including a measurement section disposed intermediate the first end and the second end, the tubular body (602,651) defining a fluid passage extending along the longitudinal axis through the tubular body (602,651) from the first end to the second end; at least two ultrasonic transducers (620,621) disposed on opposing sides of the tubular body (602,651) and spaced apart along the longitudinal axis; and at least two reflective elements disposed on the opposing sides (605,606) of the tubular body (602,651) and spaced apart along the longitudinal axis, wherein the piping arrangement (601,650) comprises: an outer pipe body (610,652); and an inner sleeve made from a polymeric material, the inner sleeve being disposed within the outer pipe body (610,652), and wherein the inner sleeve defines the measurement section and the fluid passage of the piping arrangement (601,650), characterized in that the outer pipe body (610,652) is made from a metallic material, and wherein the inner sleeve is over molded within said outer pipe body (610,652), and each of the at least two reflective elements is disposed on a respective bracket inserted in the fluid passage, and, preferably, each bracket is removably inserted in a slot (637,638) defined in an interior surface of the inner sleeve and extending along the longitudinal axis from a respective one of the first end and the second end of the tubular body (602,652) to the measurement section. a piping arrangement (601,650) comprising a tubular body (602,651) extending along a longitudinal axis from a first end to a second end and including a measurement section disposed intermediate the first end and the second end, the tubular body (602,651) defining a fluid passage extending along the longitudinal axis through the tubular body (602,651) from the first end to the second end; at least two ultrasonic transducers (620,621) disposed on opposing sides of the tubular body (602,651) and spaced apart along the longitudinal axis; and at least two reflective elements disposed on the opposing sides (605,606) of the tubular body (602,651) and spaced apart along the longitudinal axis, wherein the piping arrangement (601,650) comprises: an outer pipe body (610,652); and an inner sleeve made from a polymeric material, the inner sleeve being disposed within the outer pipe body (610,652), and wherein the inner sleeve defines the measurement section and the fluid passage of the piping arrangement (601,650), characterized in that the outer pipe body (610,652) is made from a metallic material, and wherein the inner sleeve is over molded within said outer pipe body (610,652), and each of the at least two reflective elements is disposed on a respective bracket inserted in the fluid passage, and, preferably, each bracket is removably inserted in a slot (637,638) defined in an interior surface of the inner sleeve and extending along the longitudinal axis from a respective one of the first end and the second end of the tubular body (602,652) to the measurement section. an outer pipe body (610,652); and an inner sleeve made from a polymeric material, the inner sleeve being disposed within the outer pipe body (610,652), and wherein the inner sleeve defines the measurement section and the fluid passage of the piping arrangement (601,650), characterized in that the outer pipe body (610,652) is made from a metallic material, and wherein the inner sleeve is over molded within said outer pipe body (610,652), and each of the at least two reflective elements is disposed on a respective bracket inserted in the fluid passage, and, preferably, each bracket is removably inserted in a slot (637,638) defined in an interior surface of the inner sleeve and extending along the longitudinal axis from a respective one of the first end and the second end of the tubular body (602,652) to the measurement section.