Hundreds of workers at the Faslane nuclear base will go on strike today and take other forms of industrial action after rejecting a "derisory" pay offer.
Unite suspended a planned stoppage last month at the Clyde site but has revived action after most of its members turned down a 2% offer.
A two-hour walkout will be held from 10am at Faslane and at the Coulport naval base, followed by "staged stoppages" from tomorrow, as well as a work-to-rule and overtime ban.
The dispute is between Unite and contractor Babcock, which the union claimed was paying "eye-watering" bonuses to its senior directors.
Unite national officer Ian Waddell said: "Workers on the Clyde have had enough of below-inflation pay deals, enough of one-off pay inducements and enough of an employer that wants to impose instead of negotiating.
"We are now in the ridiculous situation where Babcock's top four directors are sharing a £7 million bonus pot and making merry with 9% increases to their six-figure salaries yet the company refuses to negotiate a basic, one-year deal that helps our members match the cost of living.
"The disparity is beyond a joke now for workers on the Clyde who have fallen behind their industry's average pay rates, following four years of real-terms pay cuts despite doing everything to help this private-sector giant fulfil its business objectives.
"Babcock Marine has been well warned about the ramifications of its grossly unfair pay policies, and its workers are no longer prepared to play the part of the poor relations in this highly profitable company."
Babcock has said it was "surprised" by the development. A spokesman added: "We have engaged with our trade unions and carefully listened to their specific concerns. We have gone back to them with a new multi-year deal, which significantly increases the consolidated pay element at their request and provides an opportunity for further reward."
The company said over the past three years it would have left staff with total consolidated pay increases of 8% as well as one-off payments totalling £1150.