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.....◆ Piston Pump Summury structure ◆





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◆Exclusive Marine Pump◆
DH-M wil always with youe wequrement with our boasting high performance of H.P. Piston Pumps ranging from fixed type fire extinguishing piston pump to be used at seacraft to H.P. Piston Pumps for desailinating plant which requires high pressurised water.
Fire suppression examination scene
Ship lower part shellfish and scaling scene
 1. Electric power connect

   1) Use a reasonable electric power

     For example: a) Below 110kgf/cm2 Motor: 1PH/3PH, 4P, 2.2kw (3HP)

     Engine: 6HP engine

     b) Below 130kgf/cm2 Motor: 3PH, 4P, 3.75kw (5HP)

     Engine: 7.5HP

     c) Below 200kgf/cm2 Motor: 3PH, 4P, 5.5kw (7.5HP)

     Engine: 11HP

   2) Use a reasonable r.p.m (60HZ: 1,750 rpm / 50HZ: 1,450 rpm)

   3) Rotation direction is not distinguished right direction from reverse direction

   4) Check both of voltage of electric source and voltage of motor wiring at the time of

     using source of electricity

     (For example: 3PH-220V/380V, 1PH-220V)

   5) Check wiring conditions at the time of using source of electricity in order not to

     occur an electric leakage


2. Installation

   1) Check inlet-outlet of pump

   2) Prevent from a water leakage and air inspiration by winding of Teflon tape

      on inlet & outlet

   3) Regarding to inlet hose, make a pipe (hose) laying by flexible hose in

     consideration of water treatment capacity of pump

(For example: pump spec- 200kgf/ cm2, 16 L/min at 60HZ)

a) In case of using service water, use hose of 3/8 hole size at normal water


b) in case of using water in tank, use hose over hole size 6

4) In case of using water in tank, water-level will be same with pump level or

 higher than pump-level

5) Use a clean water for inflow water into pump and prevent inspiration of other

   material by installation of filter on suction  line

6) Tighten bolt connection between pump and motor in order to endure their


7) Select and reasonable nozzle in consideration of required pressure &

flow capacity

8) Regarding to outlet hose (pipe) material, use it as follows

a)      Pressure: below 150 kgf/ cm2 use hose of 175 kgf/ cm2

b)      Pressure: below 250 kgf/ cm2 use hose of 275 kgf/ cm2

* For this hose material, as hose diameter is changed based on hose length,

Please inform us before you select your hose

9) Dont make to twister both of inlet hose and outlet hose

Especially, be careful inlet hose side


3. Working finishing

1) Take off the suction hose from the water tank and try to emit water in the hose

2) Adjust a engine out put by low pressure and turn off a starter

3) Keep a pump in cleanness after whole removing of water into pump & hose


4. Notice for operation and treatment

1) Check direction of nozzle at the time of jet

2) Dont tighter pressure adjustment handle of by-pass excessively

3) Dont stand up nearby at the outlet side of by-pass

4) Always check it whether oil on gauge is located in appointed point or not

5) Use appointed oil (SAE20-30) or the same grade oil.

6) Change oil completely after using 100 hours based on first operation and then

change oil every 1,200 hours periodically.

7) Temperature of inlet water shall be below 40 degrees(C)

8) Inlet filter shall be checked & inspected periodically

9) Necessarily check oil statement of pump & engine before operating

10) Dont make empty rotation over 5 minutes without water connection

11) Dont control over the rated pressure or the rated engine output power

(For example, over 100 ~ 110 kgf/ cm2)

12) Be careful of damage by heavy strike

13) Keep a pump after water is removed completely in the winter

14) Keep a pump in the room in order to prevent breakdown in the winter or fill

antifreeze in pump

15) Dont make to twister both of inlet hose and outlet hose especially, is careful

inlet hose inside

16) When you use pump, you had better to rest it about 10 minutes per 1 hour


17) Dont shoot toward person or animals directly


5. Emergency measures during operation

1) When the engine is not started

l       Check if a gasoline is in it or not

l       Remove a dust of air-cleaner and re-start a engine

l       Check a engine oil

l       Check the lighting on spark plug and re-start

2) When the pressure is not occurred

l       Check if a water is supplied softly or not (Cleaning filter)

l       Check an other materials in check valve on the pump

3) When the pressure is not occurred suddenly

l       Check if water is supplied softly or not(Checking of balance water in tank)

l       Check if an air is leaked into water connection joint or not

l       Check if a water is leaked the below side from pump or not


6. Exchange period & way of consumption parts

1) Oil of pump & engine

: Change oil after 50 hours use from the time of the first use and then change oil

every 500 hours periodically

2) Pressure gauge

: When the operation is bad

3) Hose

: Every about 12 months (When hose is torn)

4) Gun & Lance

: Every about 12 months (When the rotation nozzle is worn)

5) V-Packing (ring) **

A. Exchange period: (Refer to the attached drawing of pump) 밑줄을 그으세요!

a. When it is occurred a water leakage under joint of Head (no.1) and


b. When the pressure is fallen down much lower than first pressure in spite of no

regulation of by-pass(pressure adjustment valve)

c. When the time is passed away 300~400 hours after use

(Only, it is no problem to keep use if the pressure is not fallen down)

B. Disassembly:

a. Unite 8 pieces of screw bolt (no.2) on Head(no.1)

b. Pull out Head lightly

(Don’t strike it strongly. It can give damage to piston)

c. Put a finger into v-packing housing (no.37) and pull out it and, in case of

middle ring(no.40) same too

d. V-packing (no.38), head ring (no.39) & v-packing (no.45) shall be

Exchanged necessarily and other parts shall be exchanged upon each


C. Assembly:

Assembly sequence is no.39, no.38, no.51, no.40, no.39, no.45, no.37 by turn

(When you are assemble them, please watch out that you shall not to give

them a injury. Especially, assemble them after greasing them)

6) Check valve **

A. Exchange period: every about 12 months

a.       When the pressure is not occurred at all (Change after checking it)

b.      When vibration of pump is very severe suddenly

B. Disassemble:

a.       Disassemble check cap( no.5: 6ea) of Head

b.      Pull out check valve(no.6) of check cap(no.5)

C. Inspection:

a.       Check if other materials is between valve site and valve

b.      Check if unevenness is occurred  between valve site and valve

c.      Check for a damage of o-ring(no.4)

D. Assembly

a.       Grease on o-ring(no.4) and insert it

b.      Grease on valve & valve site(no.6) and insert it

c.      Grease on o-ring(no.4) and then bolt check cap(no.5)

HEAD OFFICE and 1st Factory:626-5, Bulno-dong, Seo-gu, Incheon, 404-270 Korea
TEL:82-32-527-5782 FAX:82-32-562-4659
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