One of the largest dry-docking yards in Australasia seems likely to reopen as a joint venture with Singapore's Keppel Corp., which is aggressively seeking overseas sites.

Keppel and Maritime Engineering Pty. Ltd. of Brisbane in northeastern Australia signed an agreement in principle to revive the Cairncross dry dock.The facility, with an 85,000-deadweight-ton dock on the Brisbane River in Queensland state, was closed in 1987.

Maritime Engineering, formed in 1980, has become a significant ship repairer at the Port of Brisbane. Its Marinet Pty Ltd. unit was granted preferred lessee status on the dry dock by the Queensland government a year ago.

Under the proposed deal, which requires various government approvals, Marinet and Keppel would run the yard as a joint venture known as Keppel Cairncross Dry Dock Australia Ltd.

This would be a 24-hour integrated repair and refurbishment facility able to take ships up to Panamax size, the largest that can traverse the Panama Canal fully laden at around 64,000 dwt.

"There are limited dry-dock facilities of such size offering services to ships plying in that region," said Loh Wing Siew, an executive director of Keppel Corp., which is 38 percent owned by the Singapore government.

"The Queensland government is keen to reactivate the facility, and Keppel is capable of fulfilling this need. We see a potential demand for ship repair services in that region."

Trevor Remphry, managing director of Marinet, said the revived yard could ''be one of the most efficient" in the Southern Hemisphere. He forecast it would attract "a substantial share" of repair work from the southwestern Pacific and other areas.

Keppel operates yards in Singapore, the Philippines, India and the United Arab Emirates in the Persian Gulf. It has extended its reach in recent years as business choked some facilities at home and costs continued to rise.

If all approvals are granted, the two sides hope to begin operations next July.

Separately, Kepphil Shipyard Inc. is floating 250 million shares, or about 27 percent of its equity, to the public in the Philippines and overseas. This initial public offering comprises 100 million new shares and 150 million existing shares being sold by parent Keppel Philippines Holdings Inc.

A block of the latter's stake is reserved for minority shareholders, employees and associates of the holding company and of Cebu Shipyard & Engineering Works Inc., another yard owned by the firm.

Kepphil is consolidating its main yard and adjacent Philippine National Oil Co. Dockyard & Engineering Corp., which it bought from the government energy firm. Together, they occupy some 85 acres at Batangas south of Manila.

Kepphil's original yard can handle ships up to 20,000 dwt. It has dry- docking capacity of 110,000 dwt. in three floating docks and a shiplift serving eight repair berths.

Proceeds from sales of the new shares will go to expand and upgrade the Kepphil yard. The rest is earmarked for future investments by the holding company, including a stake in a power barge project.