Jääkatsetused

Baltic workboat ice trials 1 Target Ice trials are arranged to verify the capabilities and performance of the Vessel in ice. The Vessel is to be tested [both astern and] ahead operation mode in the specified ice conditions. The target of the ice trials is to: a) verify the ice breaking capability of the vessel in level ice and b) optionally adjust the propulsion system for optimal ice performance. 2 Phases 2.1 Planning phase The planning phase is to be finalized well in advance before the expected test period. The planning phase will consist of: 1. Identification of the vessel's performances to be measured 2. Ice sea trial procedure drafting, including at least: • List of all tests to be conducted • Procedures for each test (including the identification of all equipment and tools necessary for the test, identification of available signal from ship system suitable for the test purpose) • Procedures for ice properties assessment (including the identification of all equipment and tools necessary for the test) 3. Preliminary assessment of geographical location where the test is to be carried out 4. Planning of the whole test activities including requirements in terms of technicians, equipment, tools, cooperative means, etc. 2.2 Monitoring of ice condition development Monitoring of ice condition development, to be performed before the Vessel sails for the Ice Trials. 2.3 Ice Trial Preparation Ice trial preparation includes the following tasks: • agreeing on the responsibilities of different parties • travel arrangements for test personnel • co-ordination and communication with the vessel personnel • planning of video and photographing • packing and transportation arrangements of the equipment needed in the tests • possible instrumentation and cabling needed onboard the vessel for machinery and navigation data measurements • arrangement of possible permits 2.4 Execution of the Test It is assumed that • The ship captain and crew will be responsible of the ship operation and ship navigation during the Ice Trials. • Each party will bring appropriate clothing and other survival equipment necessary for operations in cold climate. 2.5 Data analysis and final reporting 3 Pre-conditions 3.1 Test area Test site location to be selected before the trials. The test area has the following requirements: • Water depth - minimum • Area, where level ice typically forms with minimum amount of ridges • The minimum length per one test is approximately 5-6 ship lengths. • At minimum full power test to be made. In case time and ice area permits additional tests can also be made with various power levels and power combinations. • Tests are not to be done in vincinity of old channels as broken channels may cause cracks in ice. 3.2 Minimum level ice thickness The minimum level ice thickness for testing is approximately xx% (80%) of the maximum level ice breaking capacity. In case ice thickness measurements are to be done by people working on ice, it is also important to verify that the ice is thick enough for safe working in ice. 3.3 Vessel instrumentation The following parameters are to be logged from the ship systems. 1) Speed over ground 2) Direction 3) Latitude / Longitude 4) Shaft rpm 5) Shaft power 6) Shaft torque (if possible) 7) Thruster / rudder steering angle (in the turning tests) 8) Ship heading angle (in the turning tests) 9) Lever position (if possible) Frequency for the measurements preferably 1 Hz. This frequency is suitable for vessel performance analysis. The measurement frequency must be increased, in case more detailed analysis of machinery performance or ice loading to propulsion system is to be made. 4 Tests 4.1 Starting test in level ice When the vessel is stopped the power at the propeller will be increased with steps. After each increase the waiting time is 10 s. When the vessel starts moving, the speed is allowed to stabilise after which it will be recorded. 4.2 Speed test in level ice After the starting test, when the vessel is moving the power of the propellers are increased stepwise up to the maximum power on all propulsion units. After each increase the speed is allowed to stabilise and speed and power are recorded. After the test with maximum power the power will be decreased stepwise until the vessel comes to stop. After each decrease the speed is allowed to be stabilised and the speed and power are recorded. 5 Measurements 5.1 On ice measurements The following parameters are to be measured from ice: 1) Level ice thickness 2) Snow thickness 3) Ice samples (to determine ice strength) a. Temperature measurement b. Salinity measurement from melt ice Air temperature and water depth is to be measured. Vessel draft at the bow and at the stern is to be noted. 5.1.1 Level ice thickness Level ice thickness is to be measured beforehand with an auger and a measuring stick a to verify that ice is thick enough for testing and guarantee safe working on ice. Level ice is measured with an L-shaped stick from the side of the channel after the ship has passed through the ice. Level ice thickness to be measured at regular intervals. 5.1.2 Snow thickness Snow thickness is measured at the same time as level ice thickness. 5.1.3 Ice samples Ice samples are taken to estimate the ice bending strength. The temperature of the ice samples is measured immediately on ice. The samples are melt and the salinity of the samples is measured at a later stage. 5.2 Measurements onboard the vessel The measured parameters are indicated in Chapter “Vessel instrumentation” If possible the onboard measurements are to be measured with the same computer. In case this is not possible, the clocks of the measurement computers are to be synchronized to enable matching of vessel speed and power. In case measurement computers are not available, measurements can also be done manually logging the speed and power use during the tests. If possible all the measurements are to be done from the same location and close to the vessel bridge or from a place, where there is good visibility to ice. Subject: FW: Jääkatsetused " ORMSÖ" tüüpi parvlaevaga. Attachments: Baltic workboat ice trials 2018..pdf From: Jüri Taal [mailto:[email protected]] Sent: Wednesday, January 24, 2018 9:21 AM To: Margus Ansip <[email protected]>; Reet Laos <[email protected]> Cc: Ahti Kuningas <[email protected]>; Erik Aleksejev <[email protected]> Subject: Jääkatsetused " ORMSÖ" tüüpi parvlaevaga. Lugupeetud Majandus- ja Kommunikatsiooniministeerium ja Veeteede Amet. Tulenevalt selle aasta külmenevast talvest on tõenäoline viia ühega ehitatud “Ormsö” tüüpi parvlaevadest läbi jääkatsetus 45 cm jääs, katkestamata liinitööd. Suure tõenäosusega on selleks laevaks „Kihnu Virve“ ning katsetused toimuvad Pärnu lahes vahemikus veebruar-märts 2018 kohe, kui tekib nõutava paksusega jää. Katsetused dokumenteerib Aker Arctic Technology Inc. Merenkulkijankatu 6 FI-00980 HELSINKI, Finland Mobile: +358 50 571 5808 Fax: +358 10 323 6400 E-mail: [email protected] www.akerarctic.fi Tulenevalt varasemast kirjavahetusest sellel teemal juhindume VTA seisukohast, et piisav on kui katsetused viiakse läbi ainult ühega sõsarlaevadest (kiri 13.12.2016). Samuti juhindume Majandus- ja Kommunikatsiooniministeeriumi kirjast 09.05.2017, mille kohaselt loetakse katsetused teostatud juhul, kui need on usaldusväärselt dokumenteeritud. Eelmainitud Aker Arctic Technology Inc. korraldab ja dokumenteerib katsetused sõltumatu osapoolena oma juhendile vastavalt (lisatud käesolevale kirjale). Palume teatada esimesel võimalusel, kas nõustute meie nägemusega katsete korraldamisest ning kas Veeteede Ameti esindaja soovib katsetustest osa võtta, sellise juhul palun teatage kontaktisik, kellele katsetest teada anda. Arvestama peaks sellega, et nõutava jää tekkimisel tehakse katsetused kohe, seega on katsetest etteteatamise aeg ca 24 tundi. Lugupidamisega Jüri Taal Juhatuse liige Baltic Workboats AS Sadama 26 Nasva, Lääne-Saare v. Saaremaa, 93872 ESTONIA www.bwb.ee mob: +37253432293 fax: +3724521145 [email protected] skype: juri.taal1