The ROVs ROVOP bought include two UHD-IIIs, which are said to be the most advanced heavy-duty work-class vehicles on the market, and three HD work-class systems.
All ROVs are being supplied by FMC Technologies Schilling Robotics in Davis, California.
The first of the HDs could be delivered to ROVOP as early as this week.
Both of the UHD-III systems are to be deployed on the Ceona Amazon, which is one of global oil and gas subsea construction specialist Ceona's newbuild multiple lay vessels.
The ROVs will include Ennsub-designed ultra-deepwater launch and recovery systems (LARS), which will be fully integrated into the vessel and enable operations in harsh environment conditions through the use of active heave compensation and heavy-weather deployment capabilities.
ROVOP managing director Steven Gray signed the ROV contract with FMC Shilling Robotics president Tyler Schilling at the Offshore Technology Conference in Houston last week.
"Our investment in a further five ROVs allows us to meet strong demand from our customers," he said.
"The UHD-III is the most advanced and versatile 250 horsepower [186 kilowatt] ROV on the market and through its highly intelligent management system it offers the best performance for the most difficult deepwater tasks, including the highest thrust performance for ultra-heavy duty tasks.
"It also builds on the commitment that ROVOP and Ceona share to use technology operated by the most experienced personnel that offers a game changer for the subsea construction sector."
Among many of the UHD-III features is that with its 150hp ISOL-8 auxiliary capacity for intervention applications, the vehicle delivers combined pressures and flows that cannot be achieved with conventional ROV systems.
This allows ROV compliance with API Standard 53, which requires a secondary intervention method on blow-out preventers to close rams in less than 45 seconds and, as such, offers considerable cost reduction for secondary BOP intervention.
ROVOP's latest ROV investment comes less than three months after it took delivery of four hydraulic work-class systems.
Delivery dates on the remaining four ROVs are all during 2014.
Ceona chief operating officer Stuart Cameron said the award of the additional 250hp ROVs for installation aboard the company's flagship vessel further cemented the company's long-term partnership with ROVOP.
"These next generation vehicles are of the highest standard and complement our vision to provide a high quality and reliable service to our clients," he said.
ROVOP secured a five-year deal with Ceona to provide hydraulic, work-class services on board the company's purpose-built deepwater pipelay and construction vessels including the Ceona Amazon, Polar Onyx and Normand Pacific.
The Polar Onyx and Normand Pacific came into service last month with the Ceona Amazon due to come into service in January.
Earlier this month ROVOP contracted Ennsub to design and manufacture the ROV deployment LARS for the Ceona Amazon in addition to supplying the integrated winch and A-frame to be used on ROVOP's HD ROV delivery this month.
The LARS offers umbilical handling that prevents point loading and twisting of the umbilical cores, particularly in deep water and during high frequency cycling associated with active heave compensation.