English
中文简体Accumulator Stations Explained
Piston accumulators are a common type of hydraulic energy storage device. They provide a number of benefits that include: augmenting pump flow, improving system response, storing power for intermittent duty cycles, responding more quickly to a temporary demand, and smoothing out pulsations to compensate for leakage loss.
Bladder Accumulators
The most popular type of accumulator is the bladder, which consists of a cylindrical body and piston inside. These units can handle a higher gas compression ratio and flow rate than piston types. The most important advantages of bladder units are their fast response (less than 25 milliseconds) and good dirt tolerance, which prevents the accumulator from being damaged by particles in the hydraulic fluid.
Diaphragm Accumulators
Diaphragm accumulators are similar to bladder accumulators but are made of an elastic diaphragm rather than a rubber bladder. This type of accumulator offers the same benefits as bladder units, but the disadvantage is its slow response to pressure changes.
Spring-Loaded Accumulators
A spring-loaded accumulator works like the gas-charged accumulator, except it uses a heavy spring to compress the liquid. This design is more expensive than a bladder type and doesn't have the same reliability, but it does work well in some applications.
Other Uses of Piston Accumulators
In addition to storing energy, accumulators are used to maintain pressure in circuits when the pump is not doing work. This is useful for fixed-volume pumps that run on long holding cycles. For example, the laminating-press circuit in Figure 16-3 uses a pressure-compensated pump, but it would overheat if the circuit was not using an accumulator to maintain pressure while the pump is not doing work.
