An exhaust pipe assembly, comprising: an exhaust cavity; an exhaust port, communicating with the exhaust cavity; at least two exhaust gas inlets, communicating with the exhaust cavity, wherein the exhaust port is disposed at a first end of the exhaust pipe assembly; characterized by further comprising: a plurality of water inlets, provided in the same number as the at least two exhaust gas inlets; a first water inlet cavity, communicating with a first portion of the water inlets; a second water inlet cavity, communicating with a second portion of the water inlets; a first exhaust pipe, a second exhaust pipe, and a water outlet connector, which are sequentially connected; a water counterflow cavity, which comprises a first part of the water counterflow cavity provided in the first exhaust pipe and a second part of the water counterflow cavity provided in the second exhaust pipe, wherein first part of the water counterflow cavity communicates with the second part of the water counterflow cavity, and the second part of the water counterflow cavity communicates with an end of the second water inlet cavity located at the exhaust port of the exhaust pipe assembly; and a water outlet, disposed at a second end of the exhaust pipe assembly and provided in the water outlet connector wherein the first water inlet cavity and the first part of the water counterflow cavity each communicate with the water outlet; wherein the first portion of the water inlets and the first water inlet cavity are provided in the first exhaust pipe; the second portion of the water inlets and the second water inlet cavity are provided in the second exhaust pipe. an exhaust cavity; an exhaust port, communicating with the exhaust cavity; at least two exhaust gas inlets, communicating with the exhaust cavity, wherein the exhaust port is disposed at a first end of the exhaust pipe assembly; characterized by further comprising: a plurality of water inlets, provided in the same number as the at least two exhaust gas inlets; a first water inlet cavity, communicating with a first portion of the water inlets; a second water inlet cavity, communicating with a second portion of the water inlets; a first exhaust pipe, a second exhaust pipe, and a water outlet connector, which are sequentially connected; a water counterflow cavity, which comprises a first part of the water counterflow cavity provided in the first exhaust pipe and a second part of the water counterflow cavity provided in the second exhaust pipe, wherein first part of the water counterflow cavity communicates with the second part of the water counterflow cavity, and the second part of the water counterflow cavity communicates with an end of the second water inlet cavity located at the exhaust port of the exhaust pipe assembly; and a water outlet, disposed at a second end of the exhaust pipe assembly and provided in the water outlet connector wherein the first water inlet cavity and the first part of the water counterflow cavity each communicate with the water outlet; wherein the first portion of the water inlets and the first water inlet cavity are provided in the first exhaust pipe; the second portion of the water inlets and the second water inlet cavity are provided in the second exhaust pipe. a plurality of water inlets, provided in the same number as the at least two exhaust gas inlets; a first water inlet cavity, communicating with a first portion of the water inlets; a second water inlet cavity, communicating with a second portion of the water inlets; a first exhaust pipe, a second exhaust pipe, and a water outlet connector, which are sequentially connected; a water counterflow cavity, which comprises a first part of the water counterflow cavity provided in the first exhaust pipe and a second part of the water counterflow cavity provided in the second exhaust pipe, wherein first part of the water counterflow cavity communicates with the second part of the water counterflow cavity, and the second part of the water counterflow cavity communicates with an end of the second water inlet cavity located at the exhaust port of the exhaust pipe assembly; and a water outlet, disposed at a second end of the exhaust pipe assembly and provided in the water outlet connector wherein the first water inlet cavity and the first part of the water counterflow cavity each communicate with the water outlet; wherein the first portion of the water inlets and the first water inlet cavity are provided in the first exhaust pipe; the second portion of the water inlets and the second water inlet cavity are provided in the second exhaust pipe.