What is Dead Weight Accumulator | Construction, Working, and more

Dead Weight Accumulator uses dead weight to store oil energy. 

Construction

• It consists of a piston loaded with dead weight and moving within a cylinder which exerts pressure on the oil.
• The stroke of the piston pressure will remain constant because the load remains unchanged.
• The dead weights may be of some heavy material such as iron, concrete block or even water.
• The piston is fitted precisely in to the cylinder to minimize leakage.
• They can be used to serve several hydraulic systems at a time are used in mill and central hydraulic system.
• For minimum leakage past the piston, it must be a precision fit in the accumulator tube to ensure a long life.

Working

• When oil from pump enters through inlet port, it pushes the piston upwards against the load exerted by the dead weight placed on the platform.
• The dead weights are used to maintain oil pressure for changing of the accumulator.
• When piston moves from lower end to upper end, the accumulator get charged and when it is connected to the application point, the oil under pressure releases energy through the outlet A.
• When pistons moves down completely, the accumulator is unloaded and discharge.
• The accumulator pressure is given by,Where,
  d = Diameter of piston
  W = Deadweight
  w = Piston and Piston rod weight
  And volumetric Capacity of weight loaded accumulator is given by,
  Vacc = π/4 x (d2) x L
  Where,
  L = Piston stroke length

 Symbol

Advantages

1. It supplies oil at constant pressure.
2. Simple in construction.
3. It can serve several hydraulic systems at a time.
4.  It can supply a large volume of fluid under high pressure.
5. Limitations of weight loaded accumulator.
6. They are bigger in size and much bulky as compared to others of the same capacity. They consume more space and need heavy structures to support them.

Disadvantages

1. It has larger size.
2. More space is required hence not suitable where space is limited.

Applications

• Due to their size, their applications are limited to stationary equipment such as heavy-duty presses, where large volumes are required.