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2. INTRODUCTION
This section provides an overview of the Hale Master Intake Valve (MIV) currently in production.
Additionally, the section provides information about How to Use This Manual and the Principles
Of Operation for the Master Intake Valve.
2.1. Overview
The Hale Master Intake Valve is a NFPA compliant large diameter intake valve that is mounted in
the pump suction tube behind the pump operator panel. The valve is a butterfly type valve that is
available either in manual or electric operation. Safety features on the valve include an integral
relief valve and air bleeder valve tap that vent to the atmosphere. The valve assembly, less relief
valve, is factory tested to 600 PSI (41 Bar).
The Hale Master Intake Valve has a 6.4 inch (163 mm) diameter bore with a butterfly disc de-
signed to provide minimum flow restriction when the valve is open. The unique design of the
valve and butterfly permits the valve to provide full water flow up to 1500 GPM (5678 LPM) from
draft through a single 6 inch NST suction hose when mounted on Hale pumps directly to the
main suction inlet under all standard operating conditions. Due to the design of the valve, there
is minimum friction loss and pressure drop across the valve.
When the valve is ordered as part of a Hale Midship fire pump, the pump will pass UL require-
ments up to 1500 GPM (5678 LPM) from draft through a single 6 inch NST suction hose with the
valve in place. When two valves are mounted to the fire pump the pump can achieve UL flows up
to 2000 GPM (7570 LPM) from draft through dual 6 inch NST suction hoses. The disc design
also permits easy maintenance and lubrication of the valve disc. The disc is coated with nitrile
rubber material that is compatible with most chemicals in use on the fire ground.
The valve is available configured for manual operation using a panel mounted handwheel (MIV-
M) or for electric operation using a panel mounted switch (MIV-E) for remote control operation.
Whether the manual or electric operated valve is installed, lights on the panel placard will illumi-
nate to indicate if the valve is open, closed or traversing from one position to the other.
Also provided with the electric valve is a manual override handwheel that permits valve operation
from outside the operator panel. No special tools or part removal is required.
The valve gear actuator, manual or electric, is designed to move the valve disc from the fully
closed to full open position using 10 turns of the handwheel. The electric operated valve will cy-
cle from the fully closed to full open position in no less than 3 seconds therefore meeting NFPA
requirements. The matched gear set is designed to permit operation with minimal torque even at
high flows and pressures. The design of the gear actuator also permits the valve to be placed
into a partially open position if it is necessary to gate the intake flow.
Master Intake Valves are provided with a ¾ inch NPT suction hose priming port. This port is lo-
cated near the relief valve mounting flange on the valve body. During pump operations when an
MIV is installed on the main pump suction it may be desirable to pre-prime the suction hose so
firefighting capabilities are not lost when switching from tank to draft operations.
Since the valve mounts behind the operator panel, between the suction tube extension and the
suction tube, or in-line for front and rear suction piping, there is less panel clutter, obstruction of
valve handles or chance for damage to the valve body due to overhang beyond the apparatus
running board.
The surface between the mounting flanges and Hale MIV valve body are sealed using reliable O-
ring seals in grooves machined in the Hale MIV body.
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