NEW YORK (AP) _ Stock prices moved broadly higher today, inspired by a drop in interest rates that many Wall Streeters expect to continue.

The Dow Jones average of 30 industrials rose 24.19 to 1,806.81 by 2 p.m. on Wall Street.

In the broader market, gainers outpaced losers by nearly 3 to 1 among New York Stock Exchange-listed issues.

Big Board volume was 89 million shares with two hours to go.

The market turned upward last week, following a bond market rally sparked by completion of the three-day, $28 billion Treasury refunding. Interest rates slipped further today in the credit markets, and many economists expect rates to keep falling if retail sales and industrial production statistics to be released later this week show continued sluggishness in the U.S. economy.

NL Industries common stock, adjusted for the spinoff of its chemicals business, was the most active NYSE issue, rising 7/8 to 4 1/2 as 2.06 million shares changed hands. Investor Harold Simmons on Friday said he had raised his stake in NL to 51.1 percent.

Hammermill rose 5 to 64 in heavy trading. The company said it reached a definitive agreement for International Paper Co. to purchase all its outstanding common shares for $64.50 each. International fell 1 to 63 5/ 8 .

Precious metals mining issues rose as platinum and gold prices soared on fears that South Africa could halt platinum exports if slapped with economic sanctions. ASA was up 1 1/4 to 35 1/2 , Hecla 1 3/8 to 11 and Homestake 1 1/8 to 25 3/8 .

Among blue chips, IBM was up 1/4 to 130 1/4 , AT&T 1/4 to 24 , Alcoa 1 3/8 to 35 5/8 , Union Carbide 3/8 to 21, General Electric 1 3/4 to 75, and General Motors 1 7/8 to 72 1/8 .

The NYSE's composite index of all its listed common stocks was up 1.82 to 138.23 at noon on Wall Street.

The American Stock Exchange's market value index was up 1.60 to 266.50.