A-Series Internal Pilot with Threaded Connection

Models

AAP: Cast Iron
ACP: Cast Steel
ASSP: Stainless Steel

API 520 & 614 Approved
Chatter-free operation
Mount in any position
Suitable for continuous duty

Size Range: 2.5″ and 3″
Pressures: 50 – 500 psi
Flow Rate: 150 – 350 gpm

INSTALLATION, MAINTENANCE & OPERATION

Installation

Fulflo valves can be mounted in any position. A tee may be inserted in the pump discharge line to mount the valve. The pipelines carrying the heavy valves must be well supported and overhung weights avoided. The correct size of the valve must be used, preferably equal to the size of the pipeline to which they are connected. Threaded valves (AAD and ACD) may be threaded into pipe nipples. Overhung weights on threads should be avoided. The outlet of the valve should be piped to the supply tank unless specific applications call for alternate piping of return lines. Care must be taken to have the discharge well below the oil level in the tank to prevent air entrainment and erratic operation.

Setting Valves

The valve may be set with a hydraulic hand pump for cracking pressure. If a test stand is available, the valve should be connected to the discharge header with the pump bypass open, and the bypass gradually closed until the desired pressure registers on the gauge. For Pilot Operated valves, adjust valve adjusting screw until approximately 5-7 GPM is flowing through the valve, at that point, the main piston will open, and then the valve will be considered at the setpoint, then lock adjusting screw. If a valve is required to bypass a given amount of fluid at a given pressure, a test stand having a flow meter in the a pump discharge line must be available. With a valve adjusting for cracking pressure as above, continue closing the bypass until the required flow registers on the flow meter and observe pressure. Readjust pressure, if necessary, to obtain desired pressure at desired flow.

Maintenance & Operation

Fulflo valves provide reliable “chatter-free” operations when the system is free of abrasives and foreign matter. Continuous filtration of the liquid used is strongly recommended.

TYPICAL DISASSEMBLY OF STANDARD TYPE VALVE

To dismantle valve for inspection or cleaning:

Remove cap “A” and gasket “D”
Remove nut “C”
Remove adjusting screw “B”
Remove cap screws “E”
Remove bonnet “F”
Remove gasket “G”
Remove pilot spring “J”
Unscrew and withdraw cylinder “M” (do not unscrew cylinder retainer “L” until this step is complete)
Unscrew and remove cylinder retainer “L” (after removing cylinder “M”)*
Unscrew and remove piston retainer “K”
Remove retaining ring “H”
Remove pilot piston “N”
Remove balance spring “O”
Remove piston “P”
Remove retaining bushing “S” if necessary

*CAUTION: Hold in vise–balance spring “O” is under heavy compression

Inspect bores of both piston retainer “K” and cylinder “M”. Inspect pistons “N” and “P” for wear or scoring. Replace broken or damaged parts. Clean all parts thoroughly and re-assemble as follows:

Reverse process of disassembly from operation 15 to 6 above
Thread adjusting screw “B” into bonnet “F”, while re-assembling bonnet “F” to body “R”
Then proceed with steps 5, 4, 2 & 1, above, in reverse order.