Organized labor has announced that it will endorse Arthur S. Flemming, a Cabinet member under President Eisenhower and a former U.S. commissioner on aging, as a "public candidate" for the board of Beverly Enterprises, the largest nursing home chain in the nation.

Flemming's candidacy is the first national effort by the AFL-CIO Food and Beverage Trade Department, which represents 2.5 million workers and 15 unions, to elect a candidate without strong labor ties to a corporate board.

Flemming and labor leaders stressed in interviews yesterday that, although they share concerns about health care for the elderly, Flemming would serve as a "consumer advocate" to the board if elected May 26, not as a mouthpiece for organized labor.

"There should be a consumer representative on the boards of companies involved in activities which have such a significant impact on the lives of older people," explained Flemming, who was chairman of the U.S. Commission on Civil Rights until last year and is a former secretary of the Department of Health, Education and Welfare.

Beverly board Chairman Robert Van Tuyle called Flemmings' candidacy another tactic by the union to "confuse, confound and harrass management." The Pasadena, Calif., company operates 478 nursing homes in 31 states and the Wisconsin Avenue Nursing Home in the District. About 10 percent of the company's 39,000 employes are union members. Three affiliates of the FBTD are trying to organize Beverly Enterprise nursing homes.

Besides asking stockholders to vote for Flemming, the labor unit also is trying to defeat the acquisition of $30 million of Beverly stock by Hospital Corporation of America, the nation's largest hospital chain. HCA also is involved in an organizing dispute with an FBTD affiliate. It already owns about 18 percent of Beverly stock.

Flemmings' candidacy is the boldest and most public effort to date by organized labor's new Corporate Division, a tiny office that was organized at the FBTD after the Amalgamated Clothing & Textile Workers Union forced J.P. Stevens & Co. to sign a contract. For 16 years, the ACTWU tried to get the textile manufacturer to bargain, but despite walkouts, strikes and a national product boycott, it refused. In 1980, the company suddenly signed an agreement.

J.P. Stevens acknowledged last year that it settled because of pressure caused by a corporate campaign devised by an ACTWU employe who later left the union. As part of that campaign, the ACTWU ran candidates against Stevens' board members; threatened to strike companies that were unrelated to Stevens, but whose corporate officers served on the Stevens' board; and disrupted annual stockholder meetings. The union also threatened to cause a directorship battle at Metropolitan Life Insurance Co., which controlled credit lines to J.P. Stevens.

The FBTD's corporate unit has experimented with similar tactics on a smaller scale. In the District, it kept a bank from opening a branch outlet by filing a complaint with federal officials about insider loans by board members. During an organizing campaign at restaurants in the Watergate complex, the FBTD contacted brokers in Europe who had invested European union pension funds in the restaurants and asked them to consider withdrawing the funds. And the FBTD accused Beverly Enterprise's nursing home here of numerous health violations last year, resulting in an investigation and a city health board reprimand to the company.

"We try to investigate every aspect of the business' life," explained Jeffrey Fielder, who heads the corporate division. "If it's legal, it's fair game, and we use that information to apply pressure."

The unit's four investigators develop "corporate profiles" for organizers and negotiation teams and teach members of FBTD affiliates how to investigate companies. The unit also has written a 58-page Manual of Corporate Investigation, which gives local organizers step-by-step instructions on how to investigate a company.