301Fa: Partial Module - Accumulators

Question 1

Hydraulic accumulators perform the following four functions:

Answer 1

• Energy storage
• Shock absorption
• Gradual pressure buildup
• Constant pressure maintenance

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Question 2

List two safety precautions that must be observed when working on hydraulic systems that contain accumulators.

Answer 2

• Never use oxygen or compressed air in gas-charged accumulators
• Always discharge or isolate systems equipped with accumulators prior to performing service

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Question 3

What is the purpose of the spring-loaded poppet valve in a bladder style gas accumulator?

Answer 3

Prevents the rubber bladder from being pushed through the port if the gas pressure becomes too high in relation to oil pressure in the oil chamber.

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Question 4

What are three types of accumulators used in hydraulics?

Answer 4

• Weighted
• Spring-Loaded
• Gas-Charged

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Question 5

Spring-loaded hydraulic accumulators deliver a constant force on the piston. (T/F)

Answer 5

False

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Question 6

What type of gas is used in hydraulic accumulators and why?

Answer 6

Nitrogen
Does not react with hydrocarbons.

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Question 7

What are two basic types of gas-charged accumulators?

Answer 7

• Piston
• Bladder

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Question 8

What are the main differences between piston and bladder type gas accumulators?

Answer 8

Piston: A piston rides in a cylinder which seperates the gas chamber from the oil chamger

Bladder: Oil in the accumulator acts on the surface of the rubber bladder

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