Large-format industrial duct during its fabrication process.
Project fact sheet
Client
Codelco, Salvador Division
Industry
Mining and copper smelting.
Location and period
2022.
Asset type
Process gas conveying system, in continuous 24/7 operation.
Operational situation
The original design fell short when operating conditions exceeded what it was designed for.
Service conditions
Gases with 10 % SO₂, temperatures of up to 90 °C and positive and negative pressures.
Invenio scope
Design, fabrication, and installation of the complete system.
Construction system
FRP-PVDF dual laminate: PVDF chemical barrier over an FRP structure.
Photographs
Fabrication record of the pants duct.
Confidentiality
Published case
Verification during execution
The system was fabricated and installed under dimensional control and chemical-barrier continuity verification before commissioning.
The challenge
The existing system had been conceived for a previous condition. Operation changed and the replacement solution had to respond to corrosive gases, elevated temperature, positive and negative pressure, and continuous service, without repeating the same design basis.
The duct had to operate under gases with 10 % SO₂, temperatures of up to 90 °C, positive and negative pressures, and uninterrupted 24/7 operation. The challenge was to develop a solution prepared for the current process conditions.
The solution
The project was resolved with an FRP-PVDF dual laminate duct system. PVDF was defined as the barrier in contact with the medium and FRP as the load-bearing structure.
The scope comprised design, fabrication, and installation of the complete system, with sections and interfaces defined for installation.
The result
The result was a system built for the new operating conditions, with a projected service life of over 20 years.
Fabrication, field work, and documentation
What was controlled and what was recorded, as documented during execution.
01Shop fabrication of the system, with the thermoplastic barrier and the FRP structure executed as a single laminate.
02Continuity control of the chemical barrier before dispatch of each section.
03Dimensional verification of sections and interfaces before leaving the shop.
04Transport and lifting of the sections to their installation position.
05Joints executed in the field and verified before commissioning.
06Delivery of as-built fabrication and installation drawings.
What comes after commissioning
A dual laminate system remains in service as long as its chemical barrier stays continuous. That is verified by inspection: condition of the interior laminate, joints, supports, and the zones where condensation concentrates the attack.
The inspection plan and the maintenance scope are defined for the service conditions of the system.
Fabrication record
Photographs of the pants duct fabrication process.
Enlarge imageClose image
Large-format industrial duct during its fabrication process.
Large-format industrial duct during its fabrication process.Enlarge imageClose image
Mold and support structure during fabrication of the pants duct.
Mold and support structure during fabrication of the pants duct.Enlarge imageClose image
Pants duct section loaded onto a truck for transport to the field.
Pants duct section loaded onto a truck for transport to the field.Enlarge imageClose image
Interior view of the pants duct during its fabrication.
Interior view of the pants duct during its fabrication.Enlarge imageClose image
Pants duct parts in the fabrication yard.
Pants duct parts in the fabrication yard.Enlarge imageClose image
Lift of a pants duct section during its fabrication.
Lift of a pants duct section during its fabrication.
Do you have a duct system that process conditions have outgrown?
Send the conveyed medium, the temperature, the pressure regime, and the routing. With that we can say whether the problem is solved by replacing a section or by redesigning the system.
