Abstract: A water-ring vacuum pump including a built-in hogging flow path. The water-ring vacuum pump includes a first-stage body, a second-stage body, and an impeller. The first-stage body includes a gas inlet port through which gas is suctioned and a seal water supply port through which seal water is supplied. The second-stage body includes a mixed fluid outlet port through which a mixed fluid of the gas and the seal water is discharged. The first-stage body has a fluid-mixing space provided therein, the fluid-mixing space having a mixed flow of the gas and the seal water therein. The second-stage body has a fluid guide space and an internal hogging flow path provided therein, the internal hogging flow path communicating with the fluid guide space.

Abstract: Disclosed is a liquid-ring compressor including a bypass pipe, in which the bypass pipe is directly mounted to a main body of the liquid-ring compressor, thereby greatly reducing costs incurred in the installation of a facility or a system including the liquid-ring compressor, and also economically reducing maintenance costs. The liquid-ring compressor includes a main body accommodating a shaft centrally mounted therein to receive rotational force from a driving motor, a rotor configured to rotate together with the shaft inside the main body, a suction port formed at a portion of the main body, a discharge port formed at another portion of the main body, a bypass pipe mounted between a position adjacent to the suction port in the main body and a position adjacent to the discharge port in the main body, and an opening/closing valve mounted in the middle of the bypass pipe.

Abstract: Disclosed is a liquid-ring vacuum pump that enables a worker to inspect components provided in a main body from the outside using a see-through device without disassembling the main body and to easily remove foreign matter from the main body merely by demounting the see-through device from the main body. The liquid-ring vacuum pump includes a main body, which accommodates a shaft centrally mounted therein to receive rotational force from a driving motor and has a mounting hole formed therein so as to communicate with the interior of the main body, a rotor rotating together with the shaft inside the main body, a head unit coupled to at least one side of the main body, and a see-through device, which is detachably mounted in the mounting hole and includes a see-through window member to allow the interior of the main body to be inspected with the naked eye.

Abstract: Disclosed is a component-replaceable water ring vacuum pump in which inner components within a head unit may be disassembled and replaced without separation of the head unit from a main body, thus shortening an operation time and improving operation efficiency through prevention of leakage of an inner liquid during a replacement process. The water ring vacuum pump includes a main body provided with a shaft, a rotor rotated together with the shaft within the main body, a head unit coupled to both sides of the main body, a guide bearing provided within the head unit, and a mechanical seal configured to block inner gas. A bearing bracket to support the guide bearing is detachably fastened to one side of the head unit by a bolt, and an inner cap and an outer cap are assembled to the inner and outer surfaces of the bearing bracket by fixing bolts.