How to Fabricate PIR Pre-Insulated GI Ductwork

PIR pre-insulated duct panels with galvanized iron (GI) facing provide a practical solution for modern HVAC ventilation systems. By combining a rigid PIR foam insulation core with a durable GI sheet surface, these panels offer effective thermal insulation, structural strength, and reliable performance for various ductwork applications.

Proper fabrication and assembly are essential to achieving strong connections, accurate duct dimensions, and effective airtightness. This article explains the key steps involved in turning PIR GI duct panels into finished HVAC ductwork.

Panel Measurement and Cutting

The fabrication process begins with measuring and marking the PIR GI duct panels according to the required duct dimensions. Accurate measurements help ensure that each panel fits correctly during assembly.

Depending on the duct design, workers can use different cutting methods to form the duct corners.

For standard PIR pre-insulated duct panels, 45-degree cuts allow adjacent sections to fold into 90-degree corners. Alternatively, panels can be cut at 90 degrees and joined using suitable fasteners.

For PIR duct panels with GI facing, workers can leave an additional section of the GI sheet along one edge and carefully remove the foam underneath. They then fold the extended metal facing over the adjoining panel edge and secure the connection with rivets.

This method creates a strong mechanical joint while maintaining the protective metal surface around the duct corner.

Duct Forming and Flange Installation

After cutting, workers fold or join the prepared panels to form the required rectangular duct sections.

They then install compatible PVC or aluminum flanges at the duct ends to connect individual sections. Proper flange positioning helps maintain duct alignment and provides a stable connection between adjacent duct sections.

Accurate assembly at this stage also helps reduce gaps and supports the overall structural stability of the ductwork.

Joint Bonding and Airtight Sealing

Airtight connections play an important role in HVAC system efficiency.

During assembly, workers apply suitable adhesive to the required panel joints to strengthen the connections. They also use compatible sealing materials along seams, corners, and flange connections to reduce potential air leakage.

Careful sealing helps limit air loss and moisture penetration, supporting reliable ductwork performance during operation.

Mechanical Fastening and Duct Installation

To reinforce the assembled duct sections, workers use appropriate screws, rivets, and other mechanical fasteners according to the joint design.

These fasteners help maintain secure connections and improve the stability of the completed ductwork.

During installation, workers position the duct sections according to the project layout and secure them using suitable supports and hangers. Correct support spacing and alignment help prevent unnecessary movement and maintain the integrity of the duct system.

Final Inspection and Quality Control

Before completing the installation, workers inspect the fabricated ductwork to confirm that all components are correctly assembled.

The inspection focuses on several key areas:

1.Accurate duct dimensions and proper alignment

2.Secure corner joints and flange connections

3.Complete sealing along seams and edges

4.Proper installation of fasteners and supports

5.No visible damage to the GI facing or insulation core

Where required by the project specifications, workers also perform airtightness testing to verify the quality of the completed ductwork.

Advantages of PIR Pre-Insulated GI Ductwork

PIR pre-insulated GI duct panels combine thermal insulation and a protective metal facing in a single panel structure.

Unlike conventional ductwork that requires separate insulation installation, pre-insulated panels simplify the fabrication process and help reduce additional on-site work.

The rigid PIR foam core helps minimize heat transfer, while the GI facing provides a durable exterior surface. Together, these features make PIR GI duct panels a practical choice for commercial and industrial HVAC ventilation projects.

บทสรุป

Fabricating PIR pre-insulated GI ductwork requires accurate cutting, secure mechanical connections, proper flange installation, and careful sealing.

By following a consistent assembly process, HVAC contractors can improve fabrication efficiency and produce reliable duct sections for different ventilation applications.

GFI supplies PIR pre-insulated GI duct panels and compatible duct accessories for HVAC projects worldwide, supporting efficient duct fabrication and installation.