The Soviet Union yesterday disclosed more details of the unprecedented orbital refueling of its Salyut space station and made it clear that there could be more such operatios.

The Soviet disclosed that the refueling was controlled by a computerized system of valves and pumps, using exterior pipelines between the space station and the linked cargocraft.

The system is immune against errors. It was duplicated many times and can handle not one tanker, but a few," according to Tass, the official news agency.

Tass, which said Thursday that the refueling had been completed, disclosed that the operation actually continued yesterday and one final, potentially dangerous step remains to be completed. The agency said the last of the oxidizer for the station's rocket engines had been pumped from the cargo ship to the Salyut at noon Moscow time. But the "cosmonauts are yet to blow off the pipelines (between) the docking units," Tass added.

The pipes apparently were connected automatically, and perhaps were part of the cargo craft's docking mechanism.

The cargocraft, called Progress 1, was launched toward the orbiting Salyut on Jan. 20, carrying fuel, and various other supplies. When the cargo craft is separated from the space Lab, it will carry away discarded equipment and materials to fiery extinction in the earth's atmosphere.

Meanwhile, cosmonaut Georgi Grechko moved into the record books as the man with the most time in space. His 56 days so far aboard Salyut 6, combined with 29 days he spent aboard Salyut 4 in 1975, totalling 85 days in space, topping the the American record of 84 days. That record was set in a single mission of a U.S. Skylab orbital station in 1973-74.