As part of an ongoing safety evaluation for all their products, J D Neuhaus have introduced an emergency lowering device for their EH range of air operated monorail hoists. With this feature JDN complies with the leading standards like NORSOK, specifying an emergency device for the safe lowering of loads in the event of a cut in the main power supply. This new device supplements an existing fail-safe disc brake, which is activated in the immediate event of a mains power failure, ensuring that suspended loads are held safely and securely at their above-floor level until mains power is again made available.
JDN monorail hoists with lift capacities from 25 to 60 tons can now be equipped with the latest safety development. This comprises an additional separate pressurized air reservoir tank (maintained at a mains air pressure of normally 6 bar), with a purpose built hand controller incorporating two additional pushbuttons. The controller provides positive two-handed lowering control, while eliminating the potential for unintended load movement. One button switches between normal and emergency lowering operations. The second button activates the integrated safety brake enabling the safe controlled lowering of a deadweight load. The air reservoir, which is protected by a check valve, is topped-up during normal hoist operations, and contains a sufficient air supply to complete a controlled lowering of a suspended load in the event of a loss of mains air pressure. Det Norske Veriras certification of the emergency device can be supplied where required.
The NORSOK standard covers offshore cranes as well as power driven winches and hoists. JDN can supply handling equipment that has been purposed designed for BOP handling. Other essential machinery and even emergency escape products can also be safely and effectively handled, with the additional features of controlled load lowering even in the event of a total power failure.
These JDN products are designed for working in hazardous areas and are supplied with Ex ratings for explosion risks. They are insensitive to humidity and dust while operating at temperatures from -20°C to +70°C. Instant starting, minimum maintenance and low air consumption are their positive features, coupled with compact low-headroom design. Standard features include lateral guide plates, emergency shut-off valve together with both anti-climb and anti-drop devices. Optional accessories include increased spark protection (and higher Ex rating), rack and pinion drive, overload protection, two speed trolley travel control and filter silencers.