MANILA, Philippines — Boeing Co. expects new orders from China for its 787 Dreamliner within 18 months after the nation’s biggest airlines warned of canceling purchases following delays.

“The Chinese market will continue being very interested in the airplane,” Ihssane Mounir, senior sales and marketing vice president for Greater China and Korea, said at the Beijing debut of the Dreamliner. “Will you see any more announcements in the next couple of months in China? I don’t think so on the 787. Within the next 18 months, I know” there will be, he said.

China Southern Airlines Co., the country’s biggest carrier, in October said it may cancel 10 orders after first delivery was postponed until July from around the end of this year. China Eastern Airlines Co. in the same month exchanged its 24 orders for the Dreamliner for smaller aircraft because of the delays and slowing growth in demand for international travel.

The plastic-composite 787 arrived in Beijing Capital International Airport on its first stop of a six-month world tour. It will fly to the southern cities of Guangzhou, the base for China Southern, and Haikou, home to Hainan Airlines Co., which also has orders for 10 of the Dreamliner aircraft.

Air China Ltd., the nation’s largest international carrier, would “never” change its order for 15 of the planes, Vice President He Li, said in an interview. The company is due to receive its first Dreamliner after four years, he said.

China needs 5,000 new planes valued at $600 billion through 2030 as economic growth spurs travel, while its commercial fleet will triple in size to 5,930 planes, Boeing said in September.

In total, Chicago-based Boeing has about 800 orders for the twin-aisle 787. The plane received certification from the US’s Federal Aviation Administration, the European Aviation Safety Agency and Japan’s Civil Aviation Bureau in August. The first delivery was made to maiden customer All Nippon Airways Co. the following month, ending more than three years of delays.

The first General Electric Co.-powered 787 won’t be sent to Japan Airlines Co. until early 2012 because of further testing requirements, Boeing said last month. China Southern and Hainan Airlines selected GE engines for their 787s. Air China and All Nippon use powerplants from Rolls-Royce Holdings Plc.

The 787-8 is able to fly as many as 250 passengers as far as 8,200 nautical miles (15,200 kilometers), Boeing’s website shows. The plane is also able to use 20 percent less fuel than other planes of the same size, according to the website.

Workers at Boeing’s wide-body plane plant north of Seattle have been building 2.5 Dreamliners a month since Oct. 31.

The production rate will climb to 3.5 in late winter or early spring, Jim Albaugh, head of Boeing’s commercial plane operations, said last month. It will reach five a month next autumn as the company works toward a target of 10 a month by the end of 2013.