No. 15957. Argued May 29, 1961. Decided July 6, 1961. Mr. Herbert S. Thatcher, Washington, D.C., with whom Mr. David Previant, Milwaukee, Wis., was on the brief, for petitioner. Mr. Hans J. Lehmann, Atty., N.L.R.B., with whom Messrs. Stuart Rothman, General Counsel, N.L.R.B., Dominick L. Manoli, Assoc. Gen. Counsel, N.L.R.B., and Marcel Mallet-Prevost, Asst. Gen. Counsel, N.L.R.B., were on the brief, for respondent. Mr. Harry S. Littman, Washington, D.C., filed a brief on behalf of McJunkin Corp