Capacity+ Low Profile Secondary Seal
Optimised secondary sealing for applications with limited vertical clearance
Secondary sealing solution engineered to maximise usable tank capacity while
maintaining effective vapour control and reliable performance across a range of
operating conditions.
Overview
The Capacity+ Low Profile Secondary Seal is a
high-performance secondary sealing solution designed
for floating roof tanks where vertical clearance is limited
and optimisation of usable working capacity is critical.
By combining a low vertical profile with a wide horizontal
working range, the Capacity+ enables operators to
optimise usable tank volume without compromising
sealing integrity. Installed between the floating roof and
the tank shell, the seal works in conjunction with the
primary seal to further reduce vapour emissions and
support regulatory compliance.
Manufactured using robust, spring-steel mechanical
components and a PTFE-wrapped wiper tip, the
Capacity+ is engineered to perform reliably across
variable rim gaps, challenging tank shell conditions, and
demanding operating environments.
Design & Construction
The Capacity+ seal incorporates a low-profile metallic wiper design engineered to deliver reliable secondary sealing performance while maximising tank capacity.
Key design features include:
- Low-profile configuration maximises usable tank volume
- PTFE-wrapped wiper tip provides superior abrasion resistance
- High-strength spring steel components ensure continuous sealing pressure
- Designed to accommodate wide and variable rim gaps
- Flexible installation options for in-service or out-of-service conditions
Key Benefits
Maximises tank
working capacity
The low-profile design allows operators to recover usable storage volume that may be constrained by higher-profile secondary seals.
Reliable sealing across variable rim gaps
Engineered to maintain consistent contact with the tank shell across rim space variability and shell irregularities.
Reduced vapour emissions
Provides an additional sealing layer that limits vapour escape and supports environmental performance objectives.
Durable, low-maintenance construction
Robust materials and spring-backed components deliver dependable, low-maintenance operation.
Flexible in-service and
out-of-service installation
Designed for safe and efficient installation during both in-service and out-of-service conditions.
Compliance and Standards
The Capacity+ Low Profile Secondary Seal is suited to floating roof tanks where vertical
clearance constraints and performance demands intersect, including:
- Petrochemical storage
- Fuel and hydrocarbon tanks
- Industrial storage applications
- Tanks requiring optimisation of usable working capacity
Compliance & Quality
Capacity+ secondary seals are manufactured under DirecTank’s quality management
system and developed in line with recognised industry standards and regulatory
requirements.
Materials are fully traceable, and designs support compliance with applicable air quality and
emissions control regulations, including classification as a Category “A” secondary seal
where required.