ACI Services, Inc.

Capacity Control - Unloading Devices

	Capacity or Load Control Devices for Clearance Volume Pockets Valve cap pocket, volume type with double deck valve. Used where added fixed clearance is desired, or not a problem. Provides additional valve flow area, compared to single deck valved cylinders. Valve cap pocket, volume type with half deck valve. Used where fixed clearance must be kept to a minimum while still maintaining reasonable valve flow area. Front head and body pocket, volume type. Usually can provide larger volumes than valve cap pockets. Valve cap, or front head volume pocket by-pass retrofit, a method to upgrade manual operators (handwheels) with pneumatic actuators. Conversion available for most styles. Normally requires no reworking of existing equipment. MultiPocket head end volume pockets allow for smoother transitions in load and flows. Typically, this results in increased flows per unit.
	Pneumatic Actuators Reduced Volume Demands Variable Operating Pressures Increased Discharge Pressures
	Radial Unloaders Extremely efficient Improved reliability over other types of unloaders Can be used for a wide range of gases
	Front-head Bypass (SimPlex™/DuPlex™ Unloading Devices) Versatile and Economical Provides both Clearance Volume Unloading and Efficient Compressor Head End Deactivation. Operation may be either manual or pneumatic (air or gas), with local or remote control used to open and close the bypass plug. May be supplied on new OEM cylinders or can be custom designed for existing compressors. Bypass concept provides efficiency advantages by eliminating the use of suction valve plate depressors (finger Unloading Devices) or plug type suction valve Unloading Devices SimPlex Unloader: Just the head end bypass system. DuPlex Unloader: Combines SimPlex unloader with a volume pocket.
	VariPocket™ (Hydraulic Variable Volume Pockets) The ACI VariPocket™ is an unloader device that uses only the differential operating pressures of the cylinder and allows easy adjustment of cylinder clearance while the unit is running. No external source of power is needed for movement of this variable pocket piston. Remote or automatic operation can be attained utilizing 24-volt DC solenoid operated valves and microprocessor controls. Using a customer selected parameter, the VariPocket ™can maintain maximum torque at a given suction pressure, maintain a fixed load for highest driver efficiency, or it can optimize driver operation to meet exhaust emission limits. When coupled with ACI Services, Inc.'s powerful eRCM Viewer™ computer software, operators can quickly predict unloading necessary to maintain optimum compressor operation when gas conditions change. With quick reaction to changing field conditions and precise control of equipment load, your new VariPocket can maximize returns on investments by providing additional revenues. VariPockets are available for Ajax, Ariel, Dresser-Rand, Gemini, and Superior reciprocating compressor packages, and as retrofit modifications for all late model Ajax, Superior, Cooper Bessemer, Penn, Joy and Enterprise reciprocating compressors.
	Plug-type End Deactivators Valve cap pocket, by-pass type with half deck valve. Used where fixed clearance must be kept to a minimum while still maintaining reasonable valve flow area. Valve cap pocket, by-pass type with double deck valve. Used where added fixed clearance is desired, or not a problem. Provides additional valve flow area.
	Rotary Unloaders™ Ideal way to deactivate cylinder ends via using a poppet-style valve. The Rotary Unloader does not add a bunch of fixed clearance. Thus, it is ideal for both low and high ratio applications. Can be used for a wide range of gases.