The flow system as shown in the Figure, the centrifugal pump(3500 R.P.M.) is delivering water at 100 gal/min and 70 °F into a boiler operating at a pressure of 35 psig. The water levels in the feed tank and boiler are constant. Because corrosion is expected to be negligible, select the suitable material to be used for this purpose. Assume frictional pressure drop of 5 psi across the heat exchanger. The following data are available:

Note:
(a) For NPSH required:
Total Head (ft.) 15 18 20 25 30 40
Flow rate, (gal/min) 25 30 85 105 120 155
(b) Use the physical properties of water from textbooks.
Find:
1. The suction and discharge pipe sizes
2. The head the pump must deliver
3. The break horsepower
4. The electric-motor horsepower
5. Draw the required curves
6. If cavitation will occur in the pump
7. Complete the following summary Tables (one variables and another for fittings):
Variable Suction Discharge
Flow rate (gal/min)
Density, (lb/ft3)
Pipe ID (ft)
Pipe Length, (ft)
Velocity (ft/s)
Viscosity (lb/ft.s)
Reynolds Number
Relative Roughness
Friction Factor, 4f

To answer these questions, we need to perform various calculations and refer to the available data. Let's break down each question one by one:

1. The suction and discharge pipe sizes: To determine the pipe sizes, we need to consider the flow rate, velocity, and pressure drop. Since the flow rate is given as 100 gal/min, we can use it to determine the pipe sizes. By referring to standard pipe size tables, we can find the appropriate pipe sizes that can accommodate this flow rate.

2. The head the pump must deliver: The pump head is the total energy required to move the water from the suction side to the discharge side. It includes the frictional losses and the pressure difference between the inlet and outlet. To calculate the head, we need to consider the pressure at the discharge side and the corresponding elevation difference.

3. The break horsepower: The break horsepower is the power required by the pump to deliver the required head and flow rate. It can be calculated using the following formula: Break Horsepower = (Flow rate x Head) / (3960 x Pump Efficiency).

4. The electric-motor horsepower: The electric-motor horsepower is the power required by the motor to drive the pump. It is equal to the break horsepower divided by the motor efficiency.

5. Drawing the required curves: To draw the required curves, we need to plot the flow rate on the x-axis and the head on the y-axis. We can use the available data points for NPSH required and flow rate to create the NPSH required curve. Similarly, we can calculate the head at different flow rates to create the pump head curve.

6. Determining if cavitation will occur in the pump: To determine if cavitation will occur, we need to compare the NPSH available (NPSHA) with the NPSH required (NPSHR) for the pump. If the NPSHA is greater than the NPSHR, cavitation will not occur. Otherwise, cavitation may occur.

7. Completing the summary tables: The summary tables require various calculations using the given data, such as density, pipe ID, pipe length, velocity, viscosity, Reynolds number, relative roughness, and friction factor. We can use standard equations and refer to textbooks for the physical properties of water to complete these tables.

In order to provide specific answers to these questions, additional information is required, such as the available NPSH and pump efficiency values, as well as the pipe materials and fittings.