B.F. Goodrich Co. and the United Rubber Workers union said today they reached a tentative agreement on the economic parts of a new three-year contract that could set a pattern for master contracts throughout the tire industry.

The agreement contains no concessions, but deals with "special conditions at the Akron (Ohio) location," a joint statement said.

URW President Milan Stone said if a 7 percent annual inflation rate is assumed, salaries and benefits would rise 22.5 percent over the next three years by means of the cost-of-living adjustments.

The contract also improves pension and medical benefits.

Stone and Jack W. Johnson, Goodrich vice president for labor relations, said the agreement is expected to add $2.44 an hour to wages during the life of the contract.

URW spokesman Curtis Brown said it was the earliest contract agreement ever reached in the rubber industry.

Current contracts are scheduled to expire at 12:01 a.m. Wednesday. The new contracts will cover 42,000 workers in the industry.

The union is bargaining separately with Goodyear Tire & Rubber Co. and Firestone Tire & Rubber Co.

The pact was unanimously approved as a pattern for the tire and rubber industry by a 15-member United Rubber Workers advisory committee.