Technical specification for LH-23 Lifeboat Davit Issued for information PGO GNI GNI REV.: DATE: Reason for Issue / Description: Norsafe Project No.: Project Title: Made By: Checked By: Project Approve d: Customer Document No.: Rev. No.: 1 Total Pages: 5 Norsafe as P.O. Box 115 N-4852 Faervik, Norway Tel: +47 37 5 85 Fax: +47 37 5 85 1 E-mail: mail@norsafe.com Enterprise No.: NO94411696 www.norsafe.com
1. SPECIFICATION Materials: Structural steel: Outfitting steel: Shaft steel: Manufacturing: Paint system: S355/Q345 S235/Q235 AISI 316L According to Norsafe standard TSG-1 Sandblasted to Sa 2.5 and painted with 5μ DFT zink epoxy primer or acc. to customer specification Capacity: Lifting / Lowering capacity: SWL 23 kg Gravity lowering speed: 6 m/min ±1% Lifting speed: 3 m/min Maximum operational list and trim: 2 list / 1 trim Operational temperature range: -2 C to +4 C Winch data: Wire type: Wire length included: Inner wire end: Outer wire end: Electrical data: Power supply: Heating element: Duty class: IP rating: Hydraulic data: System type: Materials: Oil filter system: ø22 mm, galvanised, non-rotating For installation height 1 m max (incl. list and trim) Secured to drum Wedge socket 38V/5Hz/3Ph or 44V/6Hz/3ph 23V / 4W in motor S2-1 min IP56 outdoors IP44 indoors DIN2353, bite type fittings Pipes in AISI 316 stainless steel Fittings & hose fittings in chromated steel + densotape Full flow 1μ nominal filtration
2. GENERAL DESCRIPTION The LH-23 davit system comprises two hydraulically powered davit arms and an electrically powered winch operating two wire falls. The davit is designed for a compact installation. It can normally be installed within two decks and the length and width will not need more space than the boat itself. The system is in compliance with latest IMO SOLAS regulation. The system provides: - Launch of lifeboat in maximum load condition - Gravity lowering of the loaded boat independent of external power supply - Retrieval of lifeboat with a crew of three persons using electric power - Retrieval of the lifeboat using manual hand crank 3. NORSAFE SCOPE OF SUPPLY Davit steel structure, complete with all necessary arrangement according to latest SOLAS regulation Electric winch with twin drums, el. motor and wire rope Electrical starter cabinet including start/stop push buttons and 42 V outlet for boat, limit switches and battery charger when required. Hydraulic Power Unit & control stand 4. YARD SCOPE OF SUPPLY Assembly, erection and welding to deck Deck reinforcement Hydraulic oil filling on winch & HPU Hydraulic connections between davit and HPU Electrical wiring to agreed interface Onboard testing according to regulation
5. SAFETY SYSTEMS Several measures have been included in the design to achieve a safe operation of the davit system for launching and recovery operations and these are: 1. Davit frame design and lifting accessories: The steel frame has been designed with a safety factor of 4.5 against the safety working load SWL and all the lifting accessories has been supplied with a safety factor of 6 against SWL. 2. HOLD-TO-RUN controls: The lowering motion is activated by pulling a remote control wire from within the lifeboat. This motion can be stopped by any time by releasing the remote control wire. Hoisting operation is controlled by a HOLD-TO-RUN push button. When the button is released the hoisting motion will stop. 3. Overload protection: A thermal overload rely in the starter cabinet protects the electrical motor against overheating in case of excessive loads. 4. Fail-safe brake: The winch is fitted with hydraulically operated multi-disc brake which is fully oil submerged. In the event of hydraulic pressure loss, due to hose or connection failure, the brake will automatically activate and davit motion will stop. 5. Hydraulic brake: A hydraulic braking system is located on the winch, consisting of a hydraulic pump, flow reduction valve and internal tank. The brake controls the speed of lifeboat descent. 6. Dead Ship operation The davit system can be operated during power loss on the ship. Gravity lowering will be activated from within the lifeboat and lowering speed will be controlled by the winch. Hoisting operation will be possible by means of a hand crank installed on the winch.
7. Limit switches Electro mechanical switches will prevent the boat from being hoisted above its upmost position / stowed position. Electrical switches on the winch provide fail safe operation of the hand crank. 6. APPROVALS AND DOCUMENTATION 3 sets of user, installation and maintenance manual in English (other languages on request) EC Type Examination Certificate (MED) Declaration of Conformity Factory Acceptance Test Report (Third Party attendance on request) Component Certificates 7. SPARE PARTS A detailed parts list is included in the instruction manual and documentation dossier. On request, a separate quotation for the supply of spare parts can be submitted. NOTE: This is Norsafe typical specification - subject to revision according to customer requirements. All products are subject to continuous review. Norsafe reserves the right to change specification without prior notice.