Diaphragm Hand Pump

You can handle any type of liquid such as clear liquid, liquid containing solids, thick liquids, viscous liquids, liquid containing abrasive solids, acid, alkali, inflammables, solvent, slurry, trash, mud water etc. Regarding viscous liquids, the maximum viscosity that can be handled can be judged by simple thumb rule, "if your liquid can be easily poured from a bucket this pump can handle it".

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2. What is the right size for me?

The pump is available in three (3) sizes with following capacity and head:

Size in Inches Tube ID	Capacity in Litre/Minute LPM	Delivery Head in Feet	Suction Lift In Feet
1”	25	30	12
1.5”	50	10	12
2”	100	0 (free discharge)	12

A. If your duty is of say, barrel unloading, or transfers to height, then 1" size (delivery head, 30 feet), is suitable. If job is repacking, then also 1" size is better suited.

B. If the duty is fast transfer, such as tanker unloading, in-plant transfer, siphoning etc. then 1.5" size at 50 LPM, 10 ft. head is suitable.

C. If duty is plain emptying or fast transfer at no head, such as pond, cellar or manhole emptying, or that in irrigation, size 2" at 100 LPM, 0 feet (free discharge) head, is better suited.

D. All the three sizes offer @ 12 ft. of negative suction in water.

E. Along with selecting size, you have to check suitable MOC.

F. If in doubt, describe your duty and name of liquid, and we will guide you.

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3. What is appropriate Material of Construction (MOC) for body and rubber parts for me?

A. Pump body and parts are offered in four materials, namely,

1. Cast Iron-Galvanized (rust-free),

2. Polypropylene (plastic, glass fibre reinforced, moulded),

3. Stainless Steel 316 (Investment cast, graded),

4. Alloy-20 (Investment Cast)

B. Rubber parts, namely, Diaphragm and Flap-Valves, are offered in six (6) different rubber materials, namely,

1. Nitrile (Buna-N)

2. Chloroprene (Neoprene ®)

3. EPDM (Nordel ®)

4. Hypalon ®

5. Silicone

6. Viton ®.

C. For general guidelines, visit Section 4, on MOC.

D. For specific liquid/s, you must provide details, like name of liquid, its pH (if acidic), content/s of mixture (if it is a mixture), solids present, if any, nature of solids (soft/abrasive, small/large) etc. for appropriate MOC recommendation. The details are also given in Section 7 Contact us page.

E. In final selection, MOC of body and rubber parts, both must be suitable for
the liquid.

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4. Why pump in Alloy 20, is offered only for Sulphuric Acid 98%?

Conc. Sulphuric Acid 98% is a very difficult liquid to handle in smaller quantities. For that duty, we offer Alloy 20 pump with Hypalon® rubber parts. This pump is offered in 1" size only. Even though Cast Iron also works for this duty, it has limited life. So we offer Alloy 20, which is an expensive alloy, but is fully resistant to this service.

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5. What is Investment Casting?

Investment casting process is a metal casting process (also known as lost wax process) which is ideally suitable for complex metal shapes and high grade of alloy. We offer our SS316 and Alloy 20 pump and its parts, in investment cast construction for clear geometry and precision grading. Some manufacturers offer SS 316 pumps in fabricated and welded construction, which is subjected to stress corrosion on welded joints. Investment casting process is most expensive of all casting processes and offers the best casting in surface finish and in purity of alloy grade.

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6. What details do I need to furnish for an enquiry for my application?

You need to tell us name/s of liquid to be handled, their pH (if they are acidic), constitution of mixture (if liquid is a mixture of many parts), solids present, nature of solids (size/soft/abrasive etc.). If you want to pump it to height, then what the height is. If it is negative (underground) suction, what the depth of liquid is.

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7. Which parts require repairs?

Normally life of diaphragm and flap valves is high, if properly selected. However you may keep one diaphragm in spare. Flap valves wear out only in case of abrasive liquids, or due to chemical attack. Body and its parts do not wear out and hence do not require to be kept as spares.

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8. Are replacement parts expensive?

Except for Viton® rubber parts, all other diaphragms are low cost. Generally speaking, diaphragm needs change only after long usage.

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9. What is life of diaphragm?

Life of diaphragm depends upon liquid to be handled and cannot be specified. But in case of our pump we have done some innovative improvisation. We have put diaphragm movement limits on link that connects diaphragm to handle. This prevents overstretching of diaphragm on upper and lower end of stroke. Overstretching is one of the major reasons for diaphragm breakage, and that factor is fully taken care of.

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10. Is changing of diaphragm simple?

Changing a diaphragm involves opening of four bolts from body, and four from diaphragm centre. It does not take more than ten minutes to change a diaphragm.

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11. Is changing of flap valves simple?

Changing a flap valve involves opening of eight bolts from suction/delivery spout flange. It does not take more than ten minutes to change a flap valve.

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12. What is life of pump body and parts?

Life of pump body and parts, if not attacked chemically, is long and never require change.

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13. Why is pump trolley mounted?

Operator of pump has to place his foot on the trolley platform so that when lever is moved to and fro, pump is steady. Pump is mounted on trolley so that it can be taken