Vice President Walter F. Mondale accepted petitions yesterday bearing more that 100,000 signatures that he described as an "eloquent plea" for continued protection of the specialty steel industry against foreign imports.

Rolled up like steel coils, the petitions from steel workers and their families in six states were lugged into a White House conference room where Mondale accepted them on behalf of President Carter.

The petitions were aimed at persuading Carter to accept the recommendation of the International Trade Commission to continue the three-year import quotas imposed on specialty steel from overseas from 1976.

"The jobs of 65,000 steelworkers and the economic health of our communities depend upon your decision," the petitions read.

Prior to the imposition of the quotas, unemployment in that sector had soared to 40 per cent, according to an industry statement issued yeaterday.

Meeting with Mondale yesterday were House members and district leaders of the United Steelworkers union from Pennsylvania, Illinois, Ohio, maryland, New York and Connecticut.

Richard P. Simmons, president of Allegheny Ludlum Steel Corp., spoke for industry officials at the meeting.

Mondale told the group the President is directing "a high-level intensive, government-wide effort" to deal with current economic problems of the domestic steel industry. The vice president promised to report to Carter on the meeting "and indicate the impressive nature of these petitions."

Meanwhile, a spokesman for American industrial valve manufacturers urged vigorous federal enforcement of laws against the dumping of imported valve products.

Jerome O. Hendrickson, president of the Valve Manufacturers Association, said the survival of the $1.7 billion U.S. industry and the jobs of 100,000 American workers are at stake.

Imports of foreign steel "pale in the face of a 40 per cent share of the American market that foreign producers now hold for certain types of valves," he said in an address to the Fliud Controls Institute.

And the Lykes Corp. yesterday said it lost $117.2 million in the third quarter from the shutdown of production at its Youngtown, Ohio, steel facility.

Lykes is the holding company for Youngstown Sheet & Tube Co., which closed its Campbell works recently.

Lykes said its third quarter figures include a pre-tax charge of $138 million for the writeoff of that facility, employee termination benefits and a loss from operations of the Campbell works during the shutdown period.

The company is discontinuing production of hot rolled sheets and plates, cold sheets and other products at Campbell.

The third quarter loss compared with a profit of $6.6 million (45 cents a share) for the same period a year ago. Sales were $478.2 million, up from the $410.8 million a year ago.

For the nine months, the company lost $175.4 million compared with earnings of $23.9 million ($1.90) a year ago on sales of $1.35 billion compared with $1.22 billion.