A.1.Kurva pump
Pump curve is very important, because of the curve can be read capability of a pump at every point can be determined so that the work flow, total head, efficiency, NPSHR, and the driving power required (maximum P1).
A.1.1. pump discharge
Discharge or flow pump is determined in accordance with the requirements for each application. Judging from the construction of the pump, the pump discharge is strongly influenced by the diameter of the impeller, the impeller diameter the greater the greater the ability of the pump discharge. As shown above, the value read on the pump discharge line of the horizontal axis with the symbol of the letter Q and usually use units of m3 / h, l / minute (lpm), liters / second (lps), gallons / minute (gpm) with the following conversion:
1m3 / h = 1 / 0.06 lpm = 1 / 3.6 lps = 1 / 0.227 gpm.
A.1.2. total head
The total pump head or pressure is determined from the piping system used in the field. Judging from the construction of the pump, the pump pressure depends on the magnitude of a large number of impeller diameter impeller and arranged series. The larger the diameter of the impeller and a growing number of impellers, the higher the pressure of a pump. As in Figure 4.1.1. total value of pump head legible on axis vertical line with the letter H emblem and usually use units of meters, feet (ft), bar, atm (atmosphere), psig, with unit conversions as follows:
1m (H2O) = 3.28 feet (H2O) = 1 / 10.2 bar = 1.45 psig
A.2. characteristics of Pipe
A.2.1. open system
Illustration piping with an open system is as in Fig. below and shown in fig. 4.1.2.1b that the starting point of the pipeline curve starts from H1 = Hg + Hs (Static head + head = geodetic suction head) or in other words that while the pump off / on, the system has received pressure pipes for H1 meters
Discharge or flow pump is determined in accordance with the requirements for each application. Judging from the construction of the pump, the pump discharge is strongly influenced by the diameter of the impeller, the impeller diameter the greater the greater the ability of the pump discharge. As shown above, the value read on the pump discharge line of the horizontal axis with the symbol of the letter Q and usually use units of m3 / h, l / minute (lpm), liters / second (lps), gallons / minute (gpm) with the following conversion:
1m3 / h = 1 / 0.06 lpm = 1 / 3.6 lps = 1 / 0.227 gpm.
A.1.2. total head
The total pump head or pressure is determined from the piping system used in the field. Judging from the construction of the pump, the pump pressure depends on the magnitude of a large number of impeller diameter impeller and arranged series. The larger the diameter of the impeller and a growing number of impellers, the higher the pressure of a pump. As in Figure 4.1.1. total value of pump head legible on axis vertical line with the letter H emblem and usually use units of meters, feet (ft), bar, atm (atmosphere), psig, with unit conversions as follows:
1m (H2O) = 3.28 feet (H2O) = 1 / 10.2 bar = 1.45 psig
A.2. characteristics of Pipe
A.2.1. open system
Illustration piping with an open system is as in Fig. below and shown in fig. 4.1.2.1b that the starting point of the pipeline curve starts from H1 = Hg + Hs (Static head + head = geodetic suction head) or in other words that while the pump off / on, the system has received pressure pipes for H1 meters
A.2.2. closed system
Illustration of a closed system as in fig. below (the circulation of hot water from the heater to the storage tank), and the other is the curve of fig pipe closed system that shows no pressure at pump dead / alive.
To avoid errors in the selection of pump drive power (electric motors and diesel engines), it should be noted that the power going to the pump. Pump power into 4 as distinguished as in fig.
B.1.Daya pump drive
Pump driving force is often called P1 (see fig.), The power required to drive the pump. Pump drive can be either electric motors or diesel engines. P1 formulation is written as follows:
P1 = P2 x η Watt motors ......
P2 = P3 Watt ......
where:
P1: Power-drive (electric motor / diesel engine)
P2: shaft power
ηmotor: efficiency motors
P3: pump shaft power
B.2.Daya hydraulic pump
As in fig. hydraulic power pump or P4 written formulation as follows:
P3 = P4 x η pump ...... Watt
P4 = ρ x g x H x Q ...... Watt
where:
P3: pump shaft power
P4: hydraulic power pump
ηpompa: pump efficiency
ρ: density of water: 1000 kg / m 3
g: acceleration of gravity: 9.8 m / sec2
H: total pump head: ... .. meters
Q: pump capacity: ... .. m3 / h
B.2.3 drive maximum pump power (P1 max.)
To determine the amount of power driving the pump (electric motor / diesel engine) must be selected maximum power (P1 max.), Which is determined at the point of the power curve Q & H work far right (see fig.), This is to prevent overload locomotion or prevent loss of pressure in the pipe due to the throtle / strangulation excessive. Selection of pump power P1 max. must be adapted to the standard power an electric motor or diesel engine in the market.
As an example of the curve below, that at some point the pump working at 140 m3 / h @ 45.2 meters elected P1 = 25.4 kW of power, but power is power that should be used at the point of work Qmax is the working point on the curve to the right, thus driving the used is an electric motor with power P1 = 30 kW.
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