New concept of icebreaking railway ferryboats for Vanino-Kholmsk line was represented at Conference of British Royal Institution of Naval Architects
On 28.04.2015, Marine Engineering Bureau's report "NEW ARCTIC CLASS FERRY FOR SAKHALIN REGION" was introduced at Ice Class Vessels Conference of British Royal Institution of Naval Architects (RINA).
Report's authors are: Gennadiy Egorov (the Marine Engineering Bureau General Director, RINA Fellow, prof., Dr. Sc.) and Igor Ilnitskiy (the First Deputy of Marine Engineering Bureau General Director, RINA Fellow, Head Designer of CNF11CPD prj.).
In the report it was marked that marine railway cargo-passenger ferry crossing Vanino-Kholmsk ensures more than 3/4 of all cargo transportation between the Sakhalin Island and continent and about 1/4 of passenger transportation.
The first part of existing crossing Vanino-Kholmsk was solemnly opened on 27.06.1973; the second one started work in 1985. Extent of the line through the Strait of Tartary is 140 miles. As width of the Sakhalin railway track (1067 mm) differs from all-Russian one, the bogies replacement is carried out in the port of Kholmsk.
It is interesting to note that actually the crossing which provided a reliable communication between the island and the continent appeared in the 50th years of last century. The 728P ferryboats "Transbaikali'e" and "Priamury'e" served it; they were constructed at Amur Shipbuilding yard in 1956 and 1958 correspondingly.
Today three 1809 ferryboats "Sakhalin-8", "Sakhalin-9" and "Sakhalin-10" work at the railway ferry line "Vanino - Kholmsk"; these vessels are of R1 restricted navigation region type. Totally 10 such ferries were constructed at the Kaliningrad Shipyard "Yantar" during the period from 1972 to 1992. Seven of them were discarding after full resources consumption. It is clear that service life of the remained vessels is not boundless and new ferries are necessary for replacement.
In accordance with estimates of DNIIMF experts, the main problems of the existing diesel-electric "Sakhalin" type vessels are as follows: insufficient seaworthiness; excess still water fuel consumption due to the additional resistance of the fore screw; insufficient manoeuvrability when calling to the Kholmsk port because of actually single-shaft and absence of side thrusters; the bad visibility from the wheel house; "breakage" of the electrical scheme; low economic efficiency.
Insufficient ice-passing and decrease of operational quality of existing "Sakhalin" type ferryboats due to hull and machinery physical wear leaded to the situation when time of crossing increased from 8 to 14-18 hours.
Since the end of the 90th years, after opening the automobile communication from Vanino to Khabarovsk and Komsomolsk-on-Amur, the Sakhalin Shipping Company started transportations not only railway wagons but also automobile transport. Main part of cargoes occupies car trains with perishable goods and other consumer goods which share steadily grows. According to the experts, by 2025 the need for goods transportation between Sakhalin and continent will make about 9.2 million tons due to coal production increase at Uglegorsk region and need for delivery of construction materials for new power generation facilities and processing industry.
Thus the remained three vessels periodically are not able to serve the declared cargo volume already now due to their navigable restrictions. For example, in November-December, 2010 OJSE "Russian Rail Ways" was compelled to declare the "convention", i.e. a prohibition of cargo loading for Sakhalin consumers because of more than 1100 wagons were already accumulated for transportation to the island. The reason was bad weather because of which ferryboats (their number was 4 at that moment) staid for 26 days, and in other days it was necessary to give a half of capacity to car trains. Such "conventions" happen during the autumn-winter period practically every year.
By request of Maritime and River Fleet Federal Agency of RF Ministry of Transport, Marine Engineering Bureau developed new concept of the CNF11CPD new generation automobile-train icebreaker ferryboat of unrestricted navigation area for Vanino-Kholmsk line with double-shaft four-engine propulsion system and three side thrusters. This concepts accumulates experience of the existing vessels and a line conditions.
New concept is a result of complex investigations carried out in 2012-2013 by Marine Engineering Bureau in interaction with lead native and foreign scientific institutes including Aker Arctic Technology (vessel's contours recommendations, ice model tests), CSRI of Marine Fleet (technical decisions examination at all design stages, vessel's contours forming, economical calculations and situation modeling), State scientific Center named for academic A.N. Krylov (model towage tests, self-running tests, sea keeping tests, checking tests in the ice tank), design bureau of wagon department of OJSC "Russian Rail Ways" (checkup of an opportunity of trains transportation onboard the ferry).
It is supposed that the new train ferries will work using existing old ferry moorings and simultaneously with the existing "Sakhalin" type ferries for some time; the new vessels should replace the old ones step-by step.
Therefore, the rolling-onto and arrangement scheme for the wagons is (four tracks edgewise), ferryboat width and ferryboat- bridge connection are remain unchanged. Thus Kholmsk port restrictions don't allow to increase significantly length or draught of the vessel.
Existing ferryboats have R1 restricted navigation region type. New ferryboats have unrestricted navigation area and have no weather restrictions accordingly.
"Sakhalin" type ferry boats have SINGLE fixed pitch PROPELLER fore and single one aft. Such design was normal for the end of 60-s of previous century, when the ferry boats were under design. There were big problems with producing high power reliable thrusters in the USSR; this moment fore/aft propeller scheme is an archaic one.
Due to hydro-meteorological point of view the negative features of the sea port of Kholmsk are rip current and standing waves at the internal water area that complicates entering the port. Currents along coast should be pointed also; they quickly turn slow vessels at the port entrance. Thereof recently usual practice became to enter the port at high speed that increases probability of collisions, creates additional waves at port water area and contradicts the common ideas concerning navigation safety in ports waters.
Therefore new ferry boats have improved steerability that provides safe entering into the port of Kholmsk.
Fore/aft propeller scheme set tactics for entering into the port, namely to cross the port of Kholmsk entry at quick full astern moving; vessel has no chance to reflect side forces from wind, waves or current. Vessel's propellers are located in CL and correspondingly are useless at low speeds, so vessel may be shifted sideways.
Also it may be marked that the most part of equipment of "Sakhalin" type ferryboats is taken out of production now.
New train ferry tactics for entering to the port of Kholmsk is very another in accordance with her abilities.
The new ferry doesn't demand risky entering into the port at high speed for providing her steerability. The ferry runs within port stern-forward at speed less than 3 kn; in such case there is no reduction of thrusters' efficiency.
The new ferry wind area (side profile) is of 2250 sq.m. for the worst case at not full draught (6.5 m) with car trains on upper deck. At the worst wind direction (perpendicularly to CL) the ferry can withstand 18 kn wind with zero (!!!) shifting by work of thrusters only; side thrusters' capacity is of 3x76 kN. Allowable wind speed increases significantly if one take into consideration drift resistance and work rudder-propeller unit (double shaft type).
Accepted decisions provide independent mooring and long-run astern movement through constrained port basin of the ports of Vanino and Kholmsk, crossing the port of Kholmsk entry gate at astern moving with the speed that ensures stable vessel's steering.
For information, the characteristics of manoeuvrability of the new vessel normalized by RS Rules are as follows: course keeping parameter E1 = 0.048, efficiency at shoal parameter E2 = 0.080, the straightforwardness of the movement at gale parameter E3 = 0.079. Same time normative efficiency of single rudder (foreseen for vessel) is Ep = 0.062; total efficiency of both rudders is 2 x Ep = 0.124. Thus, efficiency of vessel's manoeuvrability is 0.124/0.080 = 1.55, i.e. bigger than required value more than 1.5 times.
Voyage duration at Vanino - Kholmsk ferry line is about 80-90% of the round voyage, i.e. about 20 hours in a day. That is why hull have got contours of enough speed vessel; simultaneously hull contours provide seasonal independent work in heavy ice.
The new CNF11CPD ferryboat's speed is of 18 kn at 85% usage of engines' power (existing ferryboats have speed about of 16 kn). Onboard the CNF11CPD ferryboat two main engines serve every propeller; this is well known decision from European ferryboats. Such engine-propeller scheme allows to keep 12 kn speed at economic regime and 18 kn speed at full speed regime. Hull contours were developed with help computer modeling and validated at towing tanks of State Scientific Center named for academic A.N. Krylov and Aker Arctic Technology.
Functioning feature of "Vanino-Kholmsk" ferry crossing is seasonal independent work in difficult ice conditions; heavy ice situation appeared for 3-4 months in a year at a short part of voyage route (at the Vanino settlement region). At emergence of the "ice river" vessels with the ice category ARC 5 and higher are allowed to call to the port of Vanino only.
But as the incident with the tanker "Igrim" shows that in hard situations category ULA (ARC 7) is required. This tankers had ice category UL (ARC 5) and power of 7.8 MW but was pressed against ice foot by the "ice river" at the distance of 3 cables from shore.
In winter of 2011-2012 timeout of 143 vessels made 299 days for weather waiting; in 2013 ice restrictions for vessels' class was used for 52 days, in 2014 they were used for 26 days.
As the analysis of operational conditions shows, during winter-spring navigation the perspective vessel has to run with a speed about 6-8 kn through 80 cm regular ice and with a speed about 3 kn through 1.0 m regular ice.
The ice running characteristics of the CNF11CPD automobile-railway ferryboat were received as a result of the carried out researches. On the basis of towing tank tests, the limit ice-passing capability will make 1.16 m for speed of 3 kn at full forward running, 0.84 m for speed of 6 kn at full forward running and 0.68 m for speed 1.5 kn at full astern running. Moreover, structure of fore and aft ends is designed for higher ice category (Arc 7); together with Icebreaker 6 level ice-passing this allows to provide (unlike the existing vessels) independent operation of the new ferry in severe ice conditions at a short part of voyage route (about 30 miles at the Vanino settlement region). In turn it will allow avoiding considerable timeout of the ferryboat waiting for the icebreaker conveyance or excess expenses in case of individual conveyance.
In due time ferry line was created for servicing of rail way transportation; last time automobile transportation occupies bigger part of ferry lines. New kind of cargo, namely hard trailers and passenger cars have appeared. Transportation of the cargo of passenger cars will be increased due to Lidoga-Vanino highway building. Shippers have got one more potential new cargo for ferry line, namely containers and roll-trailers with heavy mechanisms. Therefore while keeping ability of rail way wagons carriage (total tracking length is of 440 m for the new ferry and of 420 m onboard existing one) the automobiles capacity increased by 2.6 times (cargo compartments total length is of 1036 m for the new ferry and of 394 m onboard existing one). As a result the following amount of automobiles can be placed onboard the new ferry: 48 trucks with semitrailers (total length 12.0-13.5 m) and additionally 28 passenger cars.
Restricted stay in the port is required in order to provide single-day voyage and stable timetable, so complete cargo and passenger operations should take 2 hours. Correspondingly aft ro-ro cargo handling scheme is used (with berth rail way bridge usage).
Besides the aft cargo handling scheme which is unambiguously intended for terminals of the Vanino and Kholmsk ports, there is a side ramp for work with ro-ro units directly from/to the berth; that allows usage of the new vessel, for example, for commercial voyages to Japan. The concept contains ability to load car trains and passenger cars directly on the ferryboat's main deck from the shore platforms which are assumed to be constructed during reconstruction of the line's terminals.
Passenger capacity of existing train ferries is fully needed because ferries became single available passenger transport mean for the biggest part of Sakhalin people due to high cost of air tickets.
The number of passengers (150 people) accepted in the new project reflects the peak line need at a season summer vacations and is set according to the offer of the Sakhalin Region Government; it is essentially important to provide solving of a social problem of recreation providing for the region's population. From 150 passengers 5 ones at enhanced single cabins, 42 ones at double cabins with water closets, 9 ones at triple cabins, 44 ones at four-berth cabins and 50 ones at saloon chairs.
Vessel's equipment provideŻ ability to work during voyage at full or partial power plant's capacity, to effect main engines maintenance without withdrawal ferryboat from operation.
Thus Marine Engineering Bureau in creative interaction with the leading domestic and foreign research institutes developed CNF11CPD new generation car-railway ferryboat for the Vanino-Kholmsk line in accordance with technical specification of Maritime and River Fleet Federal Agency; this concept provides in comparison with the existing "Sakhalin" type vessels:
• enhanced cargo capacity (truck cars capacity is 2.6 times bigger);
• weather restrictions absence (unrestricted sailing region);
• ability of working in severe ice conditions (at speed of 6-8 kn in 80 cm ice and speed about 4,5 kn in 1.0 m ice);
• ability to carry out independent (several times per day) moorings without towing assistance; ability for long reverse movement through constrained water area of the port of Kholmsk;
• ability to keep up daily cycle of round voyage (operation speed is 18 kn);
• 2-hours staying for loading-unloading operations.
The new concept carries up to 150 passengers and is able to transport dangerous goods.