The submarine James K. Polk completed the 2,000th underwater patrol for the missile-carrying submarine fleet as it docked here today under an archway of water from welcoming Navy tugs and before a platform of dignitaries.

The nation's 41 nuclear-powered missile-carrying submarines have completed more than 100,000 days, or over 275 years, of undersea patrolling without an accident or firing any of their weapons in anger, Navy admirals said as they welcomed the Polk.

Two U.S. nuclear attack submarines have been lost, the Thresher in 1963 and the Scorpion in 1968. The Scorpion was carrying nuclear warheads, but not missiles.

The Navy broke its traditional secrecy by announcing ahead of time when the Polk would dock at Charleston after steaming 60 days along a secret route. A major reason for staging such a public welcome is to attract more sailors to the submarine service.

The Navy is so short of submarine officers that those remaining in service must spend an inordinate amount of time on the patrols considered essential to deterring nuclear war.

Vice Adm. John G. Williams Jr., head of the submarine service, said here today that the Navy needs 20 to 30 percent more submarine officers to provide a better balance between time ashore and time under the sea.

Sen. Strom Thurmond (R-S.C.), a member of the Senate Armed Services Committee, hailed the submariners in the keynote speech today "for your patriotism and your love of country." He pledged that Congress will continue to give extra support to the military, including additional pay raises.

The Polk, like the other missile submarines that have been patrolling since 1960, carries 16 missiles, each with up to 14 nuclear warheads.

The idea since 1960 has been to keep the submarines hidden in case it should be necessary to retaliate against the Soviet Union for a surprise attack on the United States.

A new breed of submarine, the Trident, armed with 24 missiles, is undergoing sea trials. The warheads on the Trident I missile and the Trident II missile under development are credited with enough accuracy to enable them to destroy Soviet missile fields in a disarming first strike, if that should become national policy.

Adm. H.G. Rickover, director of Navy Nuclear Propulsion, was among the officers who hailed the Polk for completing the 2,000th missile submarine patrol. Wrote Rickover: "Since the USS George Washington initially departed on patrol on 15 Nov. 1960, the fleet ballistic missile submarines have fulfilled an essential role in our nation's strategic defense."

After these and other statements were read to the families assembled to greet the crew, the officers and men of the sub ran over the gangplank and hugged the wives and children who had not seen them since March.