Heuristic (engineering)

Examples

Storage Vessels

• Use vertical tanks on legs when the tank is less than 3.8 m³.
• Use horizontal tanks on concrete supports when the tank is between 3.8 and 38 m³,
• Use vertical tanks on concrete pads when the tank is beyond 38 m³,
• Liquids subject to breathing losses may be stored in tanks with floating or expansion roofs for conservation.
• Freeboard is 15% below 1.9 m³ and 10% above 1.9 m³.
• Thirty-day capacity often is specified for raw materials and products, but depends on connecting transportation equipment schedules.

  [Pumps]

• Centrifugal pumps: Single Stage: for of 0.057-18.9 m³/min, 152 m maximum head. Multistage: for 0.076-41.6 m³/min, 1675 m maximum head. Efficiency is 45% at 0.378 m³/min, 70% at 1.89 m³/min, 80% at 37.8 m³/min.
• Axial pumps: for 0.076–378 m³/min, 12 m head, 65-85% efficiency.
• Rotary pumps: for 0.00378-18.9 m³/min, 15,200 m head, 50-80% efficiency.
• Reciprocating pumps: for 0.0378-37.8 m³/min, 300 km head maximum. Efficiency is 70% at 7.46 kW, 85% at 37.3 kW, and 90% at 373 kW.