ISO 4413:2010 pdf free download – Hydraulic fluid power – . General rules and safety requirements for systems and their components.
5.4.4.4 Electrically operated valves
5.4.4.4.1 Electrical connections and solenoids
5.4.4.4.1.1 Electrical connections
Electrical connections shall be in accordance with appropriate standards (e.g. IEC 60204-1 or manufacturer
standard) and be designed with the suitable protection class (e.g. in accordance with IEC 60529).
5.4.4.4.1.2 Solenoids
Solenoids shall be selected (e.g. cyclic rate, temperature rating, voltage tolerance) so that they are capable of operating the valves at the specified conditions.
5.4.4.4.1.3 Manual or other overrides
If it is necessary to operate an electrically operated valve when electrical power is not available, it shall be provided with means for an override. Overrides shall be designed or selected so that the risk of inadvertent operation is minimized; and they should reset when the override control is removed, unless otherwise specified.
5.4.4.5 Adjustments
When valves permit adjustments of one or more parameters, the following provisions should be incorporated, as appropriate:
a) means for securing the adjustment;
b) means for locking the adjustment, if required to prevent unauthorized change; or
c) means for preventing adjustment beyond a safe range.
5.4.5 Fluids and conditioning components
5.4.5.1 Fluids
5.4.5.1.1 Specification
5.4.5.1.1.1 Fluids should be described in accordance with recognized International Standards. The manufacturer of the component or system shall define the proper hydraulic fluid by the type and the technical data or, if this is impossible, by the trade name of the hydraulic fluid’s manufacturer.
5.4.5.1.1.2 When selecting a hydraulic fluid, consideration shall be given to its electrical conductivity.
5.4.5.1.1.3 Where a fire hazard exists, consideration shall be given to the use of a fire-resistant fluid.
5.4.5.1.2 Compatibility
All components in contact with the hydraulic fluid used shall be compatible with this hydraulic fluid. Additional precautions shall be taken in cases in which problems can arise due to incompatibility of the fluid with
a) protective finishes and other fluids associated with the system, for example paints, process and/or service fluids;
b) construction and installation material that can be in contact with spilled or leaking fire-resistant fluid, for example electrical cabling, other service supplies and products;
c) other hydraulic fluids.
5.4.5.1.3 Cleanliness level of fluids
The cleanliness level of hydraulic fluids, expressed in accordance with ISO 4406, shall be suitable for the most contaminant-sensitive component in the system.
NOTE 1 Commercial hydraulic fluids might not exhibit the required cleanliness level when delivered.
NOTE 2 Contamination of the fluid can affect the electrical conductivity of the fluid.
5.4.5.2 Reservoirs
5.4.5.2.1 Design
The reservoir or combination of communicating reservoirs
a) shall contain all the fluid that can flow from the system during normal operation or maintenance in accordance with the intended use;
b) shall maintain the fluid level at a safe working height and allow sufficient fluid access to supply lines during all operating cycles and operating attitudes;
c) shall allow adequate space for thermal expansion and air separation;
d) for hydraulic systems in stationary industrial machinery, shall be installed either over a pan, or equivalent device, of suitable capacity and configuration in order to effectively collect major accidental spillage from the reservoirs [see also 5.2.5 and 5.3.1 n)], or over an impermeable area;
NOTE Design requirements in these cases can be subject to national legal provisions.
e) should be able to provide passive cooling to control the system fluid temperature; when passive cooling is not sufficient, active cooling shall be provided; see 5.4.5.4.