The acquisition would add directional drilling services — the ability to drill at an angle from a central point — to Smith's portfolio of products and engineering, the company said.
Other linkups in recent months include the $7.4 billion merger of National Oilwell Varco and Grant Prideco, announced in December, and Grey Wolf's $1.4 billion purchase of Basic Energy Services, announced in April.
Rock said the combination of Smith and W-H would "accelerate W-H's globalization" by giving its assets more exposure in fast-growing international markets, which account for two-thirds of Smith's revenues.
Ken White, W-H's chief executive, said his company has been the subject of takeover rumors for years as it competed with much larger oil field services companies.
Simmons & Co. International called the deal a win-win for both companies in a note to investors today.
And for W-H, Simmons said, the deal comes after its stock has had a "huge multi-year run," up nearly 60 percent this year following significant gains since 2005.
The companies said Smith will pay $93.55 per share of W-H Energy, a 9 percent premium on Monday's closing price of $85.54. Smith would pay $56.10 per share in cash and issue 0.48 of its shares for each W-H Energy share.
Rock declined to tell analysts whether the deal contains provisions blocking other companies from bidding more for W-H Services or specify a breakup fee in the event that it falls through. He said those details would be in a regulatory filing.
