Front-Head Bypass (SimPlex™/DuPlex™ Unloaders)Head end bypass systems offer unique unloading abilities that provide versatility and economy not possible with other types of reciprocating compressor unloaders. ACI’s SimPlex™ and Du- Plex™ devices provide efficient, front head end deactivation utilizing external bypass piping. The gas bypass arrangement provides efficiency advantages by avoiding interfering with valve performance.
The DuPlex™ device additionally incorporates a useful clearance volume pocket for applications that may require partial head end unloading as well as total head end deactivation. ACI’s bypass unloaders are applicable to both new OEM cylinders and to reapplied compressor cylinders. Device actuation can be either manual or pneumatic (air or gas). 
ACI DuPlex™ UnloaderACI DuPlex™ unloaders offer versatility and economy not possible with many other systems. They provide both clearance volume unloading and efficient compressor head end deactivation, combined in a new ACI style front head designed to replace the conventional cylinder head. These devices may be supplied on new OEM cylinders or they can be custom designed for reapplying existing compressors. The ACI custom sized clearance volume pocket provides partial head end unloading, and external piping bypassing head end compression chamber gas back to suction pressure for complete head end deactivation. The external piping typically routes gas to suction through a special ACI design valve cap, or alternately to the suction drum or suction header of the unit. DuPlex™ operation may be either manual or pneumatic (air or gas), with local or remote control. The first step of unloading opens the clearance volume pocket plug; the second step opens the bypass plug. This bypass concept provides efficiency advantages by eliminating the use of suction valve plate depressors (finger unloaders) or plug type suction valve unloaders often used for end deactivation. With ACI's eRCM™ compressor performance software, ACI can evaluate the advantages of integrating the DuPlex™ unloading concept into an existing application. Additionally, ACI can develop the optimum unloading sequence, the software for automation, or even the complete automation system. The ACI SimPlex™ UnloaderACI SimPlex™ unloaders offer a simple and economical approach for compressor cylinder head end deactivation. The system utilizes external bypass piping combined with a new ACI style front head designed to replace the conventional cylinder head. Head end compression chamber gas is by- passed back to suction pressure for complete head end deactivation. Typically, the bypassed gas is routed to suction through a special ACI design valve cap, or alternately to the suction drum or suction header of the unit. This bypass concept provides efficiency advantages by eliminating the need for suction valve plate depressors (finger unloaders) or plug type suction valve unloaders often used for end deactivation in other approaches. Operation may be either manual or pneumatic (air or gas), with local or remote control used to open and close the bypass plug. The ACI SimPlex™ system can be supplied on new OEM cylinders or may be custom designed for reapplying existing compressors. With ACI's eRCM™ performance software, ACI can evaluate the advantages of integrating the SimPlex™ unloading concept into an existing application. Additionally, ACI can develop the optimum unloading sequence, the software for automation, or even the complete automation system. |