The anticipated increase in coal production for 1977 has been wiped out by miners' wildcat strikes, the National Coal Association reported yesterday amid new signs of labor-management troubles in the coal fields.

The association said that last April's production forecast for the year of 672 million tons has been revised to 665 million tons, roughly the same as last year. The loss of roughly 7 million tons accounts for about 1.1 per cent of anticipated production, which already has been adjusted to account for ton-nake losses from the severe winter.

The new signs of trouble came as the Bituminous Coal Operators Association, the industry's contract bargaining arm, rejected a demand from United Mine Workers President Arnold Miller for a reopening of the 1974 contract that is due to expire in December.

Invoking a contract clause that permits disputes that are "national in character" to be taken back to the bargaining table, Miller asked for the reopening to permit reallocation of health and welfare funds so a cutback in medical benefits could be rescinded.

Trustees of the funds last month ordered the cutback, whoch could cost miners up to $500 a year, because of revenue shortages caused in large part by the wildcat strikes.

BCOA President Jospeh P. Brennan said he was willing to meet next week with Miller, as Miller had requested, but rejected the recently re-elected union president's contention that the UMW could reopen the contract unilaterally. "We make no commitment of any kind other than our willingness to meet," said Brennan.

Miller has contended that the companies forced the benefit cutback by refusing to reallocate money from pension to health funds. Brennan argued that the companies agreed twice before the reallocations, and said the UMW conceded at the time of the last transfer that benefits might have to be cut.

A continued impasse could lead to a nationwide coal strike before the current contract expires Dec. 6, when a national shutdown in expected anyway. But a strike has not been threatened officially. The issue may be taken up when the union's executive board meets July 21.

Meanwhile, wildcat strikes resumed this week after the miners' two-week July vacation period, idling 15,000 workers yesterday, according to BCOA figures. The BCOA estimated that wildcats thus far this year have cost 1 million man-days of work, $63.7 million is lost wages and $21.4 million in losses to health and retirement funds, which are financed by production royalties.