Each year confirmed cruise buffs with the time, the budget and a love of adventure afloat climb aboard sleek liners bound for distant ports of call. Leisurely, luxuriously, they sail on long cruises to places like Bali, Bombay, Bahia and Dubrovnik.

The travel industry considers anything over 14 days a "long cruise" -- and there are many to choose from in 1985. The newest trend is to combine separate cruises to create unusual longer packages. However, "world cruises" that roam the sea lanes for months at a time are the longest and thus most apt to stir the imaginations of sailors and landlubbers alike.Three of these vessels have already embarked from New York or Los Angeles, but cruise segments are available at various ports en route.

Here are some of those special longer cruises now being offered (all fares quoted are per person, double occupancy, and subject to availability):

* Cunard's QE2: The ship, which sailed from New York on its Golden Route World Cruise Jan. 13, has a 62-day "winter segment" that will leave Sydney, Australia, on Feb. 15. It will visit ports that include Perth, Singapore, Capetown, Sao Paulo and St. Martin, arriving at Port Everglades on April 16 and New York, April 18. Fares range from $13,470 to $66,760; for a special supplement of $2,299 per person, the Concorde will fly passengers from London to Sydney in time to board the vessel.

* Holland America's Rotterdam: Its world cruise began Jan. 6 in New York, but the last segment -- 22 days from Haifa to New York -- is available. The ship will sail from Israel on March 12, visiting Istanbul, Yalta, Odessa, Piraeus, Dubrovnik, Venice, Malta and Lisbon, before docking in New York on April 3. Fares range from $5,775 to $12,985, including air fare from New York or Fort Lauderdale to meet the ship at Haifa.

* Royal Viking Line's Royal Viking Sky: The ship sailed on a world cruise from Fort Lauderdale Jan. 19, and from Los Angeles Jan. 31. A 46-day cruise, the last segment, begins in Hong Kong on March 13, and includes scheduled stops at Bangkok, Singapore, Bombay, Alexandria, Piraeus, Gibraltar and Lisbon, ending at Southampton, England, on April 28. Fares range from $10,157 to $37,876. Passengers can fly from New York to Hong Kong to board the vessel for a reduced air "add-on" of $960.