A compressor may include a shell, first and second scrolls, a seal assembly, a modulation control chamber, and a modulation control valve. The first scroll may include a first end plate having a biasing passage extending therethrough. The seal assembly may isolate a discharge pressure region from a suction pressure region. The seal assembly and the first scroll may define an axial biasing chamber therebetween that communicates with the axial biasing chamber and a first pocket between the first and second scrolls. The modulation control chamber may be fluidly coupled with the biasing chamber by a first passage. The modulation control valve may be fluidly coupled with the modulation control chamber by a second passage and movable between a first position allowing communication between the second passage and the suction pressure region and a second position restricting communication between the second passage and the suction pressure region.

Accordingly, embodiments herein disclose a system (500) for controlling admission volume of an inlet gas for fixed RPM operation of in an apparatus. The system (500) has a boiler (502) for generating a steam at a higher pressure for heating application in a process. A pressure reducing valve (PRV) (504) controls a boiler pressure to process pressure. Inlet ports and exhaust ports are configured by intersection of opening on a rotor housing (614) and opening on a rotating valve. The inlet ports are designed in such a way that a port opening duration can be controlled to admit required volume of a steam corresponding to a mass flow requirement of the process. A port capable of changing the area and timing of opening in such a way that the duration and starting of exhaust can be controlled.

Accordingly, embodiments herein disclose a system (500) for controlling admission volume of an inlet gas for fixed RPM operation of in an apparatus. The system (500) has a boiler (502) for generating a steam at a higher pressure for heating application in a process. A pressure reducing valve (PRV) (504) controls a boiler pressure to process pressure. Inlet ports and exhaust ports are configured by intersection of opening on a rotor housing (614) and opening on a rotating valve. Inlet ports are configured so that a port opening duration can be controlled to admit required volume of a steam corresponding to a mass flow requirement of the process. A port capable of changing the area and timing of opening in such a way that the duration and starting of exhaust can be controlled.

A compressor may include a shell, first and second scrolls, a seal assembly, a modulation control chamber, and a modulation control valve. The first scroll may include a first end plate having a biasing passage extending therethrough. The seal assembly may isolate a discharge pressure region from a suction pressure region. The seal assembly and the first scroll may define an axial biasing chamber therebetween that communicates with the axial biasing chamber and a first pocket between the first and second scrolls. The modulation control chamber may be fluidly coupled with the biasing chamber by a first passage. The modulation control valve may be fluidly coupled with the modulation control chamber by a second passage and movable between a first position allowing communication between the second passage and the suction pressure region and a second position restricting communication between the second passage and the suction pressure region.

A compressor may include a shell assembly, first and second scrolls, and a valve assembly. The shell assembly may define a discharge chamber. The first scroll may be disposed within the discharge chamber and may include a first end plate and a first spiral wrap. The first end plate may include a discharge passage in communication with the discharge chamber. The second scroll may be disposed within the discharge chamber and may include a second end plate and a second spiral wrap. The first and second spiral wraps define fluid pockets therebetween. The second end plate may include a port selectively communicating with one of the fluid pockets. The valve assembly may be mounted to the second scroll and may include a valve member that is movable between open and closed positions to allow and restrict communication between the port and the discharge chamber.

A compressor may include a shell, first and second scrolls, a seal assembly, a modulation control chamber, and a modulation control valve. The first scroll may include a first end plate having a biasing passage extending therethrough. The seal assembly may isolate a discharge pressure region from a suction pressure region. The seal assembly and the first scroll may define an axial biasing chamber therebetween that communicates with the axial biasing chamber and a first pocket between the first and second scrolls. The modulation control chamber may be fluidly coupled with the biasing chamber by a first passage. The modulation control valve may be fluidly coupled with the modulation control chamber by a second passage and movable between a first position allowing communication between the second passage and the suction pressure region and a second position restricting communication between the second passage and the suction pressure region.

A compressor may include a shell assembly, first and second scrolls, and a valve assembly. The shell assembly may define a discharge chamber. The first scroll may be disposed within the discharge chamber and may include a first end plate and a first spiral wrap. The first end plate may include a discharge passage in communication with the discharge chamber. The second scroll may be disposed within the discharge chamber and may include a second end plate and a second spiral wrap. The first and second spiral wraps define fluid pockets therebetween. The second end plate may include a port selectively communicating with one of the fluid pockets. The valve assembly may be mounted to the second scroll and may include a valve member that is movable between open and closed positions to allow and restrict communication between the port and the discharge chamber.

A compressor may include a shell, first and second scrolls, a seal assembly, a modulation control chamber, and a modulation control valve. The first scroll may include a first end plate having a biasing passage extending therethrough. The seal assembly may isolate a discharge pressure region from a suction pressure region. The seal assembly and the first scroll may define an axial biasing chamber therebetween that communicates with the axial biasing chamber and a first pocket between the first and second scrolls. The modulation control chamber may be fluidly coupled with the biasing chamber by a first passage. The modulation control valve may be fluidly coupled with the modulation control chamber by a second passage and movable between a first position allowing communication between the second passage and the suction pressure region and a second position restricting communication between the second passage and the suction pressure region.

A compressor may include a shell, first and second scrolls, a seal assembly, a modulation control chamber, and a modulation control valve. The first scroll may include a first end plate having a biasing passage extending therethrough. The seal assembly may isolate a discharge pressure region from a suction pressure region. The seal assembly and the first scroll may define an axial biasing chamber therebetween that communicates with the axial biasing chamber and a first pocket between the first and second scrolls. The modulation control chamber may be fluidly coupled with the biasing chamber by a first passage. The modulation control valve may be fluidly coupled with the modulation control chamber by a second passage and movable between a first position allowing communication between the second passage and the suction pressure region and a second position restricting communication between the second passage and the suction pressure region.

A capacity modulation assembly is provided and may include a control valve and a first line extending between the control valve and a suction pressure region disposed within a compressor shell, whereby the suction pressure region is in communication with a suction inlet gas fitting extending through a shell of a compressor. The capacity modulation assembly may additionally include a second line extending between the control valve and an intermediate pressure region disposed within the compressor shell, whereby the intermediate pressure region is in communication with compression pockets defined between an orbiting scroll and a non-orbiting scroll.