STORAGE TANKS & VESSELS - Floating Roof Seals, Legs, Water Drain & Access Ladder PDF Print E-mail
Written by Norrie   
Monday, 24 May 2010 21:43
Article Index
STORAGE TANKS & VESSELS
Storage Tanks
Floating Roof Storage Tanks
Floating Roof Seals, Legs, Water Drain & Access Ladder
STORAGE OF HIGH PRESSURE GASES
1. SPHERICAL STORAGE (STORAGE SPHERES)
2. CYLINDRICAL STORAGE VESSELS
3. GAS CYLINDERS
STORAGE OF LOW PRESSURE GASES
All Pages

Floating Roof Seals, Legs, Water Drain & Access Ladder

1. SEALS:

Between the edge of the floating roof and the inside of the tank shell, special seals are fitted to minimise leakage of vapour. The seal used is generally of a continuous strip of flexible, special rubber material which is attached to the roof and to the seal ring around the inside circumference of the tank shell.

The seal ring is held against the tank wall by a counter-weighted 'Pantograph Hanger'.

The complete seal unit moves with the roof maintaining a virtually vapour tight seal.

2. ROOF LEGS:

The underside of the roof is fitted with support legs in order to leave space between the roof and the tank bottom when the tank is empty. These legs allow access to the tank for cleaning and / or maintenance.

3. ROOF WATER DRAIN:

Rainwater drains to the centre of the roof into a well or water trap. The well is fitted with a flexible pipe which runs through the inside of the tank with a check valve in the well which will open as the well fills up with water. The bottom end of the drain line is connected to an outside valve which is normally left open. The check valve also prevents tank liquid from leaking on to the tank rooftop if the internal drain pipe should leak.

4. ROOF ACCESS LADDER:

A ladder is installed up the side of the tank and over on to the rooftop. This is used for access for sampling, gauging or maintenance ..etc. As the roof moves up and down, the internal section of the ladder will slide back and forth on wheels running along a track.



Last Updated on Monday, 24 May 2010 21:47