SANDPIPER MHP2M User Manual

Model mhp2m, Service and operating manual, Principle of operation

Advertising
background image

mhp2mdl4sm-rev0513

Model MHP2M Page 1

PRINCIPLE OF OPERATION

This pump is a 2:1 pressure ratio single acting pump powered by compressed air.

The 2:1 ratio is achieved by simultaneously applying air pressure over a single end

of each of two pistons connected in series by a shaft. The two pressurized ends are

those most distant from the pumped fluid, with the force from the air pressure exerted

in the direction of the pumped fluid. The combined force is transferred through to the

single end of the piston nearer to the pumped fluid—the single piston end having an

area equal to one-half that of the two “air” ends—and then through a fluid cell to a

single pumping diaphragm.

On this single acting pump the suction stroke is independent of all discharge

conditions and requires less air pressure than the discharge stroke. The suction

stroke is accomplished through an air regulator which pressurizes the piston area

in the rear cylinder adjacent to the intermediate bracket, while simultaneously

exhausting the other two piston areas: one in the front cylinder, adjacent to the

intermediate bracket, and the other behind the rear cylinder piston, adjacent to the

cap end.

OPERATION

The regulator is factory preset to 30 psi. After the pump is installed and in

operation, the operator should raise or lower the setting until maximum

performance is determined by trial and error. A setting which is too high will result

in excessively rapid and noisy operation, with a loss in performance and eventually

shortened pump life.

The hose assemblies deliver air to the non-wetted portions of the pump, and care

should be taken that they are neither crimped nor cut.

INSTALLATION PROCEDURES

Position the pump as close as possible to the source of the liquid to be pumped.

Avoid long or undersize suction lines and use the minimum number of fittings.

For permanent installation involving rigid piping, install short flexible sections

of hose between the pump and piping. This reduces strains and permits easier

removal of the pump for service when required.

AIR SUPPLY

Do not connect the unit to an air supply in excess of 125 PSI (8.61 bars).

Install a shutoff valve in the air supply line to permit removal of the unit for servic-

ing. When connecting an air supply of rigid piping, mount a section of flexible line

to the pump to eliminate piping strain. In permanent installations, an air line filter is

recommended.

FREEZING OR ICING OF EXHAUST

Icing of the air exhaust can occur under certain conditions of temperature and

humidity on compressed air power equipment. Icing is more likely to occur at

high discharge pressures. Use of the Warren Rupp Air Dryer should eliminate the

problem.

MAINTENANCE AFTER USE

When the pump is used for materials that tend to settle out or transform from liquid

to solid form, care must be taken after each use or during idle time to remove them

and flush the pump as required to prevent damage. In freezing temperatures the pump

must be completely drained when idle. This model must be tilted to allow the liquid

from the chambers to run out of the discharge port.

I n t h e e v e n t o f

diaphragm rupture,

pumped material may

enter the air end of

the pump, and be

discharged into the atmosphere. The air

exhaust must be piped to an appropriate

area for safe disposition.

WARNING

Before maintenance

or repair, shut off the

com-pressed air line,

bleed the pressure,

and disconnect the air

line from the pump.

The discharge line may be pressurized

and must be bled of its pressure.

WARNING

B e f o r e p u m p

operation, inspect all

gasketed fasteners

for looseness caused

by gasket creep.

Re-torque loose fasteners to prevent

leakage. Follow recommended torques

stated in this manual.

CAUTION

Read these safety

w a r n i n g s a n d

instructions in this

manual completely,

before installation and start-up of the pump.

It is the responsibility of the purchaser to

retain this manual for reference. Failure to

comply with the recommendations stated

in this manual will damage the pump, and

void factory warranty.

Take action to prevent

static sparking. Fire

or explosion can

result, especially

w h e n h a n d l i n g

flammable liquids.

T h e p u m p , p i p i n g , v a l v e s ,

containers or other miscellaneous

e q u i p m e n t m u s t b e g r o u n d e d .

WARNING

IMPORTANT

SERVICE AND OPERATING MANUAL

HIGH PRESSURE DUTY Type 4

Model MHP2M

II 2G c T5

II 3/2 G c T5

II 2GD T5

Warren Rupp, Inc. • A Unit of IDEX Corporation • 800 N. Main St., Mansfield, Ohio 44902 USA

Telephone (419) 524-8388 • Fax (419) 522-7867 • www.warrenrupp.com

Advertising