ISO 5596:1999 download.Hydraulic fluid power — Gas-loaded accumulators with separator — Ranges of pressures and volumes and characteristic quantities.
ISO 5596 specifies the characteristic performance quantities required for defining, designing. arid testing gas-loaded accumulators with separator, which are used in hydraulic fluid power systems.
It also defines ranges of pressures and volumes for these accumulators.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of ISO 5596. For dated references, subsequent amendments to, or revisions of. any of these publications do not apply. However, parties to agreements based on ISO 5596 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and lEG maintain registers of currently valid International Standards.
ISO 3. Preferred numbers — Series of preferred numbers.
ISO 5598, Fluid power systems and components — Vocabulary.
3 Terms and definitions
For the purposes of ISO 5596, the terms and definitions given in ISO 5598 and the following apply.
gas-loaded accumulator
accumulator with separation in which the liquid is pressurized using the compressibdity of an inert gas (nitrogen, for example).
NOTE The separation is achieved by means of a bladder, diaphragm, piston, etc.
3.2
gas-loaded accumulator, transfer type
gas-loaded accumulator with a port for additional gas capacity from one or more gas bottle(s)
4 Applications
4.1 Energy storage
The gas-loaded accumulator stores hydraulic fluid under pressure during a period of low energy demand from the circuit in which it is mounted. The stored hydraulic fluid is then returned to the circuit to supplement or replace the pump discharge temporarily or to ensure emergency operation.
4.2 Pulse or surge damping
The gas-loaded accumulator absorbs hydraulic fluid to reduce pressure peaks and returns hydraulic fluid to compensate for pressure drops. The accumulator thus reduces the amplitude of pressure oscillations in the circuit in which it is mounted.
4.3 Thermal compensation
The gas-loaded accumulator absorbs volume changes resulting from changes in the temperature of the hydraulic fluid contained in an isolated part of the circuit.
5 Characteristic quantities
The following quantities shall be used to define and design a gas-loaded accumulator.
5.1 Pressures
P0 = pre-charging pressure. i.e., the gas pressure in the accumulator when the hydraulic circuit is not under pressure (initial state) at a temperature of 20 °C ± 5 °C.
minimum working pressure of the hydraulic circuit.
P2 = maximum working pressure of the hydraulic circuit.
p3 = set pressure of the pressure relief valve for the accumulator, if one is fitted.
p4 = allowable pressure, i.e., the maximum permissible pressure for which the accumulator has been designed and/or qualified by test.
Temperatures shall be expressed in degrees Celsius,
6 Ranges of pressures and volumes
6.1 Nominal pressure range, P4
6.3 (63)— 10(100)— 16 (160)— 20 (200)— 25(250) —31.5(315) —40 (400) —50 (500)— 63 (630)
Pressures are expressed in megapascals, with the equivalent value in bars in parentheses.
For special applications that require lower or higher pressures, use pressures corresponding to the R 10 series of
preferred numbers (see Iso 3).
6.2 Nominal volume range, V
0.25—0,4—0,5—0.63—1.0—1.6—2,5—4,0—6,3—10—16—20—25—32—40—50—63 —100—160—200
Volumes are expressed in litres.
Fof special applications that require smaller or larger volumes, use volumes corresponding to the R 10 series of
preferred numbers (see ISO 3).
7 Identification statement (reference to this International Standard)
Use the following statement in test reports, catalogues, and sales literature when electing to comply with ISO 5596:
‘Ranges of pressures and volumes, and characteristic quantities for gas-loaded accumulators with separator selected in accordance with ISO 5596:1999, Hydraulic fluid power — Gas-loaded accumulators with separator — Ranges of pressures and volumes and characteristic qua ntities.”