Design of Reservoir Cylinder & Material selection

The reservoir must be stable non-reactive material; it is not subjected to any type of stress except when the cover plate is tightened the stress resulting from this tightening action can be neglected since it may not bring significant effect.

Material selection

The reservoir only stores the oil and is not subjected to any type of iron used in pipe manufacture and can be selected as previous cylinder material but its inner walls are chromium plated to prevent corrosion and wear. All the oil that fills the main cylinder comes from the reservoir by way of the tube.

Volume of reservoir =volume of the four cylinders + volume of the tube

From geometric analysis

Let assume that h = 50cm

Let us select thickness of the reservoir t_r = 5 mm

Design of the Pumping Cylinder

The pumping cylinder is small in size when compared to the other cylinder, but is subjected to the same pressure (p = 324.8Kpa).

The analysis is the same with the previous cylinder analysis,

Material for pumping cylinder

Normalize steel of carbon content of 2% yield strength σ_y =250Mpa. This material satisfies the following criteria

• Availability
• Corrosion resistance and mechanical stability
• Manufacturing feasibility

Design analysis

The pump is subjected to both tangential and radial stress

Tangential stress  where

d₂=internal diameter

d₂^o = outer diameter

r =point of maximum pressure

The maximum pressure at r=d₂/2 thus

The tangential stress σ_t can be

From geometry analysis d₂ =60mm

Thus 

d₂^o = 67mm

Thus, thickness of the cylinder is

t₂=3.5mm = Thickness of the pump cylinder