BS EN 422-2009 pdf download – Plastics and rubber machines — Blow moulding machines — Safety requirements
5.1.3 Emergency stop The emergency stop shall stop all movement but not necessarily the heating. The stop category shall be 0 or 1 according to EN 60204-1:2006 whichever provides the shorter rundown time. See 7.1.3.
5.1.4 Fluid systems Hydraulic and pneumatic systems shall be designed in accordance with respectively EN 982:1996 and EN 983:1996. The flexible hoses for hydraulic fluids under a pressure of more than 50 bar and for pneumatic fluids of more than 10 bar shall be secured to the machine by additional fastenings (for example chains) limiting the whiplash. On machines equipped with guards, this requirement does not apply to flexible hoses situated inside the guards. However, additional fastenings for flexible hoses for blowing fluids are also required inside the machine, except if the machine is safeguarded by interlocking guards with guard locking and the pressure in the pneumatic hoses is reduced to under 10 bar before the guard lock can be released. The PL r for this safety function shall be c. To avoid injury by ejected fluids accessible hoses and connections shall be covered by guards. For hydraulic or pneumatic accumulators the following shall apply.
The operation of a protective device shall interrupt all power from accumulators for the blowing fluid or which are associated with dangerous movements.
Actuation of the emergency stopping devices or disconnection of power to the machine shall isolate all power from accumulators for the blowing fluid or which are associated with dangerous movements. Where accumulators are integrated parts of the machine, unloading shall be initiated automatically.
Visual indication of accumulator pressure shall be provided. Where hydraulic accumulators are integrated parts of the machine, the isolating valve or valves shall be position monitored. When the position monitoring system detects the valve or valves failing to isolate the accumulators, then:
an optical or audible signal shall be given; and
all accumulators connected with the failed valve or valves shall be automatically unloaded. Machines with hydraulic or pneumatic supply from an external source shall be provided with a manual isolation valve lockable by key.
5.1.5 Safeguards
5.1.5.1 Guards Guards shall be in accordance with EN 953. Guards located in areas where ejection of hot plastic can take place shall also contain the ejected material. If the movement of power operated guards can cause injury (force > 150 N or pressure > 50 N/cm 2 ), pressure sensitive edges in accordance with EN 1760-2:2001 shall be provided in order to either arrest or reverse the closing movement of the guard. Actuation of the sensitive edge shall arrest or reverse the closing movement of the guard in accordance with EN ISO 13849-1:2006 PL r = c. Reversing the movement shall not create further hazards.
5.1.5.2 Electro-sensitive protecting equipment (ESPE) ESPE may be used if the ejection of hot plastics is prevented by design of the machine. The ESPE shall be in accordance with EN 61496-1:1997 or EN 61496-3:2001 and be positioned according to EN 999:1998.
The ESPE shall become effective as soon as the blow moulding machine is switched on. It shall not be possible to reach the danger area around, above or beneath the ESPE. The end of an interruption of the ESPE shall not automatically initiate any further movement. A new start command shall be required.
5.1.6 Movements caused by gravity Machine parts which can have a dangerous movement under gravity shall be provided with an automatic blocking device which operates as soon as the corresponding movable guard is opened or ESPE is interrupted. The blocking shall remain active until a new start command is given. The required performance level for this safety function shall be PL r c.
5.1.7 Electrical hazards and hazards due to electromagnetic interference
The electrical equipment shall be in accordance with EN 60204-1:2006.