PERU LNG Raises, Secures Roof on Storage Tank

PERU LNG Raises, Secures Roof on Storage Tank

Oct 2008

Chicago Bridge & Iron successfully raised the roof on the first of two LNG storage tanks at PERU LNG’s gas liquefaction plant. “It was a flawless execution of a very complex task,” said Jim Rix, manager of construction, COLP. The construction of both tanks is ahead of schedule.

Shanmuk Sharma, project manager, COLP, had a front row seat at “mission control,” a platform perched at the top of the tank wall. From this location the CB&I team directed the activity like an orchestra conductor. “The experience and conduct of the CB&I team was impressive and made the multifaceted exercise look easier than it was,” said Sharma, adding that CB&I’s attention to safety and logistics was why it all appeared easy.

“The raising operation started at 7:40 a.m. and was completed successfully by 12:40 p.m. This is as efficient as it gets,” said Sharma. Fog was the only disappointment of the day because it blanketed the camera placed on a crane boom above the tank.

The process of installing the roof began with its construction on the floor inside the tank, said Sharma. The completed roof weighs 800 metric tonnes, and measures 256 feet in diameter.

To lift the roof into position, air is blown in beneath the roof. As the pressure builds, it lifts the roof at about 12 inches per minute. After the roof rises a few feet, it is held in position. After 30 minutes of checking that all is in order and safe to proceed, more air is applied.

When it reaches the top of the tank wall – 108 feet – an experienced crew secures it with large pins and the welding starts. When there are enough pins in place and the welding is complete, the tank wall will support the roof’s weight. At that point, the air is released. In its final position, the top of the domed roof is 182 feet high.

“It looks easy,” said Sharma, “but the preparations are exhaustive and the unique experience of the CB&I team ensures that the success of the PERU LNG plant facilities is in capable hands.”

The finished tanks will each have two walls. The inner wall will be constructed on the inside of the tank. The inner tank is made of a high nickel material to withstand the extremely low temperatures of liquid methane.


© Copyright 2024. PERU LNG - All rights reserved.