**Water Hammer Pressure and Static Head**

The given problem involves a cast iron pipe with a diameter of 1 m. The pipe is subjected to a water hammer pressure of 8 kg/cm^2. Additionally, the maximum static head on this pipe at its lowest point of enroute is 120 m.

**Understanding Water Hammer Pressure**

Water hammer pressure occurs when there is a sudden change in the flow velocity of water in a pipe. This change in velocity leads to a pressure surge, which can cause damage to the pipe if not properly accounted for. In this case, the water hammer pressure is given as 8 kg/cm^2.

**Understanding Static Head**

Static head refers to the pressure exerted by the weight of a fluid column at a specific point in a pipe. In this case, the maximum static head at the lowest point of the pipe enroute is given as 120 m.

**Determining the Thickness of the Pipe**

To determine the suggested thickness of the pipe, we need to consider the water hammer pressure and the maximum static head.

1. **Water Hammer Pressure**
- Convert the water hammer pressure from kg/cm^2 to N/m^2 (Pa).
- 1 kg/cm^2 = 10^4 N/m^2 (Pa)
- Therefore, the water hammer pressure is 8 x 10^4 N/m^2.

2. **Static Head**
- Convert the static head from meters to N/m^2 (Pa).
- The density of water is approximately 1000 kg/m^3.
- Therefore, the static head is 120 x 1000 x 9.81 N/m^2.

3. **Determining the Required Thickness**
- Calculate the hoop stress on the pipe using the formula:
- Hoop stress = (Pressure x Diameter) / (2 x Wall thickness)
- Rearranging the formula, we have:
- Wall thickness = (Pressure x Diameter) / (2 x Hoop stress)
- Substitute the given values into the formula:
- Wall thickness = (8 x 10^4 x 1) / (2 x Hoop stress)

4. **Evaluating the Required Thickness**
- To evaluate the suggested thickness of the pipe, we need to determine the hoop stress.
- The hoop stress depends on the material properties of the cast iron pipe. These properties include the yield strength and safety factor.
- Once the hoop stress is determined, substitute it into the formula from step 3 to obtain the suggested thickness of the pipe.

Therefore, to suggest a thickness of the pipe, we need to know the material properties of the cast iron pipe, including the yield strength and safety factor. With this information, we can calculate the hoop stress and determine the appropriate thickness to withstand the water hammer pressure and static head.