Parker Abex – Jet Pipe ServosElectrohydraulic ServovalvesParker Abex – Jet Pipe ServosElectrohydraulic Servovalves

• Nuclear, Steam and Gas Power Plant Applications• Unique Jet Pipe® First Stage Design

Presentation AbstractPresentation Abstract

Pedigree – Parker Non-Incendive Jetpipe Electro-Hydraulic Servovalve Design

Hydraulic Design Features & “Varnishing” Special note on A160 varnishing

Performance of Jetpipe Design Versus Flapper Style Servovalves

“Intrinsically Safe” vs “Non-Incendive” Designs

Open Questions

Presentation Abstract (cont.)Presentation Abstract (cont.)

Goal is 20 minutes ppt, 25 minutes questions/open discussion

Single task is to show how Jetpipe Servo design is more robust/fail resistant in harsh oil environments (i.e. A160 lube skid)

Presenter is Sr. Engineer at Electro Hydraulic Servovalve Division

Asst. will be handy to help with more specific 7FA related questions

Following Slides Give a Flavor of ppt

Servo Controls DivisionServo Controls Division

Uniquely positioned for the powergen market Over 40 years as a supplier to the Power Gen

Market EHSV’s specified on over 40 GE drawings Unique Jet-Pipe® construction

– 5-70 GPM 1, 2 or 3 coil models available Factory Mutual Approved Intrinsically Safe Models

by 2Q ‘04 Complete R & O facilities-to OE requirements Single sourcing within Parker enables access to

over 500,000 parts

SERVO CONTROLS DIVISION JET-PIPE OPERATIONSERVO CONTROLS DIVISION JET-PIPE OPERATION

Figure 1 — Servovalve at null

High pressure filtered fluid flows to the flexible feed pipe

attached at the base of the torque motor, to the top of the jet pipe, and out the projector jet.

Fluid from the projector jet impinges upon the receiver. Two small orifices are connected hydraulically to the ends of the second-stage spool.

With the servovalve at null, the projector jet is centered over the

receiver holes and equal pressures are developed at each end

of the spool.

SERVO CONTROLS DIVISION JET-PIPE OPERATIONSERVO CONTROLS DIVISION JET-PIPE OPERATION

Figure 2 — Actuation Input current is applied to the torque motor. A

magnetic torque is produced causing the armature and the attached jet pipe with projector jet to rotate through a very small angle. The

polarity will cause the jet pipe to move left or right.. The projector jet movement causes differential

pressure across the second-stage spool causing movement. As t he spool moves, the feedback spring pulls the jet pipe back against the magnetic torque toward the center of the receiver.

When the feedback spring force is equal to the magnetic force, the projector jet will again be centered over the receiver generating equal pressure at each end of the spool, and spool movement stops at the new position.Fluid will now flow from the second stage pressure port to the cylinder port C2, through the actuator, and back through cylinder port C1 to return.A reversal of the input current results in an opposite motion of the spool, changing the direction of the flow to the actuator.

SERVO CONTROLS DIVISION JET-PIPE SERVO VALVESSERVO CONTROLS DIVISION JET-PIPE SERVO VALVES

Excellent contamination resistance. Jet-Pipe allows larger particulate passage than nozzles.

Additionally, high spool-driving forces and long power-stage strokes help our Jet-Pipe servovalves deliver premium contamination resistance – the highest in the industry.

 The reliability leader. Rugged servovalve design and construction combine with

excellent contamination resistance to make Parker’s Jet-Pipe servovalve the industry leader in performance and reliability.

Low life-cycle costs. High reliability minimizes servovalve and actuator

maintenance, significantly reducing life-cycle costs