The standard bladder accumulator consists of a “closed” rubber bladder inside a forged steel shell. A mechanically actuated valve closes when the fluid has been expelled, blocking off the fluid port, thereby enclosing the bladder within the shell. Where high discharge rates are required, a high flow model is available. Applications with corrosive environments may require shells furnished with an internal and/or external coating or manufactured from stainless steel. The top repairable accumulator permits service and maintenance of the bladder without removing the accumulator from the hydraulic system.
When the pressure level of a system permits, a low-pressure accumulator may be used. It is similar to a standard bladder accumulator, except that the poppet valve is replaced by a perforated plate covering the fluid port, and the shell may be of welded construction. For lightweight applications, a Kevlar wrapped accumulator shell is available. The wrapping supports the thinner metal shell to provide a substantial weight reduction.