Flexible Air Ducts
class 1 flexible air duct
| Brand | shengtongJH |
|---|---|
| Procurement basis | UL 181 Class 1 where explicitly required by the project specification |
| Bore enquiries | 5 / 6 / 8 / 10 / 12 / 16 / 20 in; listing coverage checked for the selected size |
| Construction choices | Insulated or uninsulated only within the documented product scope |
| Length | Within the selected product designation and installation conditions |
| Flame-spread criterion | Index not over 25, with no continued progressive combustion under the classification |
| Smoke-developed criterion | Index not over 50 under the classification |
| Product identity | Traceable manufacturer, product designation and listing evidence |
| Air service | HVAC air distribution within the selected listing and operating limits |
| Operating ratings | Pressure, temperature and velocity from the exact product data |
| Closure materials | Compatible fastening and sealing system required by the product instructions |
| Customization boundary | Changes must remain within the applicable documented product scope |
The classification criteria describe the purchasing requirement, not a certification claim for an unspecified shengtongJH product. Confirm the exact listed assembly before purchase.
Sizes, supplied lengths and connection accessories can be selected for the project; changes affecting classification require corresponding product evidence.
Class 1 flexible air duct is a classification-led purchase. When a specification calls for UL 181 Class 1, the exact supplied duct and its documentation must meet that requirement; appearance, foil facing or insulation thickness cannot establish the classification.
Make the classification traceable to the order
The phrase Class 1 should lead to a specific product identity. Ask for the manufacturer, exact designation and listing evidence, then check that the diameter and construction being offered are covered. A report for an insulation blanket alone does not identify the performance of the assembled flexible duct.
The UL 181 scope defines the classification in terms of surface-burning criteria. That is different from a claim that the duct provides a fire-resistance period for a compartment wall. Where a route crosses a rated assembly, the penetration and fire-protection arrangement require their own project design.
Air duct or air connector?
These are distinct product designations. The applicable installation conditions can differ, so compare the label and documentation with the intended route. Do not assume that a product described casually as flexible duct can be used wherever a specified air duct is required.
Keep the assembly intact
Changing the liner, jacket, insulation or closure method may change the basis on which a product was evaluated. A custom request should identify which changes are permitted, rather than treating a familiar appearance as proof of equivalent performance.
Retain the receiving record
Match delivery labels to the approved submittal and purchase order before the material is installed. Keep product identification and installation instructions with the project records so later maintenance can select a suitable replacement.
Procurement through shengtongJH
State the required standard, product designation, size and operating conditions at enquiry stage. We handle the sourcing scope as a trader; a requested certification is not implied simply by this page title. If the proposed item lacks matching evidence, it should not be substituted into a classification-specified order. Agree a documented alternative with the project team before changing the purchase.
Sizes, supplied lengths and connection accessories can be selected for the project; changes affecting classification require corresponding product evidence.