* CEO Allister Langlands to become chairman
* Bob Keiller, head of Wood Group's PSN division, to be new CEO
* Ian Wood to retire after 30 years as chairman
LONDON, July 19 (Reuters) - Oil industry services firm Wood Group said chief executive Allister Langlands will step up to the chairman's role and Bob Keiller, currently in charge of the part of the business that maintains oil pipelines, will replace him.
The sweeping shake-up at the top of the company also involves Ian Wood, who has been chairman for 30 years, retiring.
The UK corporate governance code frowns upon the practice of chief executives stepping into chairman jobs, which can make it hard for new CEOs to challenge their predecessors' decisions.
FTSE 250 company Wood Group on Thursday acknowledged Langlands move to the chairman's position was not usual practice, but said it had consulted with shareholders owning more than 40 percent of the company, and they supported the board changes.
New chief executive Keiller is currently head of the Wood Group PSN division, a business which maintains and services the production facilities of oil companies such as Shell and Talisman, and is Wood Group's biggest division on a revenue-basis.
The management changes will take effect from November 1, Wood Group said.
Ian Wood, who owns a 5.7 percent stake in the company which was founded by his grandfather to repair ships in the early twentieth century, was chief executive of the group between 1967 and 2006.
"I have been lucky enough to participate in the very successful and exciting growth of the UK's oil and gas industry over the last 45 years and seen Wood Group become a successful global player," he said.
Shares in Wood Group were up 1.4 percent to 751.5 pence at 0731 GMT, valuing the company at about 2.7 billion pounds ($4.2 billion).