The Williams Companies, parent company of Salt Lake-based Northwest Pipeline Corp., reported a net loss of $2.2 million or $.06 per share in second quarter compared with net income of $13.5 million or $.38 per share in the same period last year.

In last year's second quarter, the company's net income included "other income" of $10.1 million from several unrelated, non-recurring credits.Six months net income was $126.4 million or $3.32 per share compared with $67.9 million or $1.96 per share for the first half of 1987.

Revenues amounted to $304 million compared with $327 million in the second quarter of 1987, and there was a loss from continuing operations of $2.2 million versus income from continuing operations of $11.1 million in the second quarter a year ago.

Revenues for the first six months amounted to $931 million vs. $863 million in the same period last year, and income from continuing operations was $31.5 million or $.82 per share compared with $31.8 million or $.92 per share in the first six months a year ago.

"As we had previously noted, our natural gas pipeline operations traditionally experience seasonal lows during the second and third quarters of the year," said chairman Joseph H. Williams.

" In the second quarter, both our Northwest Pipeline Corporation and Williams Natural Gas Company subsidiaries were also affected by delays in receiving the regulatory authority under which they could reasonably offer the permanent, open access transportation service which has been advocated by the Federal Energy Regulatory Commission."

Northwest Pipeline began offering the permanent open access transportation service to its customers on June 10, and Williams Natural Gas began offering the service on July 20.

Northwest Pipeline Corporation had second quarter operating profit of $17.7 million compared with $36.1 million in the same quarter last year, with the decline primarily attributed to increased operating expenses and the effects of a decline in its rate base and a reduction in income taxes from the second quarter of 1987.

Its combined gas sales and transportation volumes increased 15 percent from the second quarter last year, with gas sales declining 55 percent while transportation volumes increased by 56 percent.

For the first six months, Northwest Pipeline had operating profit of $58.5 million vs. $83.6 million in the same period a year ago.

"The continued benefits from our company's restructuring and improved balance sheet are evidenced in our net interest expense and investing income at mid-year, both of which are favorable to the comparable amounts reported in 1987," said Williams.

"Our sound financial condition along with the clearer scene now emerging for our natural gas pipeline operations and the aggressive growth in profitability being demonstrated by Williams Telecommunications further reinforce our optimism for the company's performance in 1988 and future years."