FAQs

/FAQs
FAQs 2018-05-15T17:52:16+00:00

 

MWI Corp’s most extensively used Pumps, “The Hydraflo”, could be used as an alternative to axial/mixed flow pumps. The Hydraflo is patented submersible pump, that use the power of hydraulics to drive the impeller via flexible hoses. This replaces a fixed motor, a long, rigid shaft and the supporting structure common to most pumps that can move very large quantities of water. It’s unique design eliminates any civil construction or installation work at site. Our units are designed to start pumping in few minutes from arrival to site needing no more than one labor to operate it, which make the units are very cost saving due to eliminate the costs of civil construction & installation works. The units could be mobile, portable or skid mounted depending on the site needs. The Hydraflo does not need priming and provide a variable speed control option. The unit can be installed Vertically, Horizontally or at any angle by simply changing the intake bell. It is the most suitable choice for irrigation, emergency cases or temporarily or seasonal pumping, bypass systems and many other applications where a huge amount of water needed to be lift in a very short time. The discharge of our mobile or electric driven units can reach 7200m3/hr and the total head can reach up to 18m.

A centrifugal pump is basically a rotating shovel for liquid. Each rotation it expels a donut of liquid. The volume of the donut represents how many m3/s the pump delivers. The liquid is thrown off the vane tips. At the center of the shaft there is no relative motion but the liquid there moves out to replace the liquid thrown off the tip. This creates a low pressure area at the shaft center, which is also the liquid inlet (pump suction). External pressure on the liquid supply, which may only be atmospheric pressure, forces more liquid into the pump suction. The amount of velocity of the liquid as it leaves the pump determines how much head (or pressure) the pump will develop. This is determined by the diameter of the vane and how many revolutions per minute it makes (shaft speed). h=V2/2g for you engineers. Pumps are designed around a flow rate which determines how big the case must be to efficiently handle the quantity of water desired. This is indicated by the inlet and outlet pipe sizes but there can be considerable variation. If it gets impractical to make an impeller large enough in diameter to get the head desired, two or more impellers (stages) can be incorporated into one housing. This is very common in water well pumps where the pump must go down a hole. 

Imagine that you have a basic water pump with the discharge connected to a short piece of pipe with a pressure gage and a gate valve in it. Suppose you shut the valve and turn the pump on. The pressure gage will reach some maximum and the flow will be zero since nothing can get past the valve. If you now open the valve a little bit there will be some flow and the pressure gage reading will drop a bit. As you open the valve more and more the flow increases and the pressure drops. When the valve is fully open you will get the maximum flow and the pressure will be zero. If you plot these readings on a graph with flow in m3/s on the bottom ( x axis) and pressure measured in meters of water on the left ( y axis) you will have a pump curve. This curve is determined by the manufacturer. It is used to tell what flow the pump will produce at any given head pressure. Note that pressure is a measure of resistance to flow. It is the total resistance in a system that determines the flow output of the pump. Without any resistance, the pump delivers its maximum flow. Pumps are quite stupid and totally unaware of what you intend them to do. They deal only in what is real to them and they don’t know anything except what is at their suction and what is at their discharge. Pump curves are customarily marked in meters of head because any liquid pumped will be lifted to the same height. This is true whether it is oil, water or molten lead. ( Pressure and energy required are another thing altogether).

A pump converts the energy used to turn its shaft into water energy. The efficiency with which it does so determines what it costs to move the liquid. It takes the same amount of energy to lift one gallon of water two feet as it does to lift two gallons one foot. The formula for water is: Horsepower = (Discharge Q in m3/s) x (Total dynamic head in meters) (Specific Weight γ 1000 kg/m3)/ 75* pump efficiency. Specific Weight γ of water =1000 kg/m3; for liquids other than water, their specific weight in kg/m3must be used.This is derived from the definition of horsepower and is always true. 75 is a conversion factor to make the units come out right. The word dynamic means the total head is figured when the liquid is in motion and so friction losses must be included. 

 A lease is a contract between the owner of an asset—the lessor—and another party seeking use of the asset—the lessee. Through the lease, the lessor grants the right to use the asset to the lessee. The right to use the asset can be for a long period, such as 20 years, or a much shorter period, such as a month. In exchange for the right to use the asset, the lessee makes periodic lease payments to the lessor. A lease, then, is a form of financing to the lessee provided by the lessor that enables the lessee to obtain the use of the leased asset.
There are two main classifications of leases: finance leases and operating leases. In substance, a finance lease is equivalent to the purchase of some asset (lease to own) by the buyer (lessee) that is directly financed by the seller (lessor). An operating lease is an agreement allowing the lessee to use some asset for a period of time, essentially a rental.

There are several advantages to leasing an asset compared to purchasing it. Leases can provide less costly financing, usually require little, if any, down payment, and are often at lower fixed interest rates than those incurred if the asset was purchased. A lease can also reduce the risks of obsolescence, residual value, and disposition to the lessee because the lessee does not own the asset. The lessor may enjoy economies of scale for servicing assets. As a result of these advantages, the lessor may offer attractive lease terms and leasing the asset may be less costly for the lessee than owning the asset. Further, the negotiated lease contract may contain less-restrictive provisions than other forms of borrowing. Therefore, this Leasing is particularly suitable for new Micro, Small or Medium Sized Enterprises (MSMEs) without a long credit history of financial statements

Leases also have perceived financial and tax reporting advantages. The lessor may be better positioned to manage servicing the asset and to take advantage of tax benefits of ownership, such as depreciation and interest. As a result, leasing the asset may be less costly than owning the asset for the lessee.

1. Agree on the following: • Leasing amount of the pumping station • Method of payment • Time instalments must be paid • Price of the unit if the Leaser decides to purchase the unit at the end of the contract. 2. Signing the contract 3. Supply of the units according to the beginning date of the contract.