You Will Benefit From

Underground ventilation duct highly-customized to meet your specific business needs based on your budget & quality requirement.

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    Competitive Wholesales Price

    Most affordable cost secured by self-made fabrics, reliable hardware suppliers and patent extrusion technology.

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    All-round Superior Quality

    Environment-friendly raw materials, self-developed PVC extrusion processing line & all ducts with NPFA 701( MSHA) approved.

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    All-in-one Precise Customization

    Offering PVC fabric Solutions to meet your global market demands by chemical performance/weight / length / width / color / etc.

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    100% Benefits Guarantee

    Up to 12-months warranty and free sample available with SGS & CE approval certification.

Submit Your Enquiry & Get New Catalog

Our expert team will answer your inquiries within 12 hours.

    Remark: The latest product catalog is available for download once your form is sent out!

    Ideal for Underground Ventilation



    Exclusive hot-welded construction (best practice technique in the industry) builds the low-leakage ducting system as the nylon fabric adheres to the PVC film seamlessly, which delivers more air to where it is needed.


    Energy Efficient

    In-house R&D experts produce durable ducts as the PVC film is made evenly by the perfect reaction of top-quality PVC resin and other chemical components.



    The flexible design in the ventilation system enhanced by exceptional performance makes the duct easy to install, extend and repair during the underground operation.

    Your Ideal Partner With 4'P's

    For engineering projects, price decides duct performance and vice versa.




    Specialists from our R&D team have been working in the underground ventilation industry for more than 30 years. To form a high-performance fabric based on customer-required performance, they make fabric ingredients with exact proportions case by case and test duct with carefulness.




    As an integrated manufacturer of PVC fabric and underground ventilation duct, Sulong can offer a production plan fit for your project budget. Our competitive pricing can make the duct textile of you-required quality.


    Product Performance

    Product Performance

    Specializing in ventilation duct and PVC fabric, Sulong can produce the textile whose physical performance is up to industrial standard and customer requirement. Our fabric performance has got wide recognition from clients who head underground ventilation projects.


    Project Provider

    Project Provider

    With advanced technologies in ducting engineering and fabric production, Sulong is confident to offer one-stop service support and on-demand product supply. Long-lasting partnerships with all types of customers have reinforced our experience and strength in the industry.

    One-Stop Ventilation Ducting Service


    Reliable Design Support

    Sulong cooperated with reliable partner Korfman extractor fan(Top 3 in its industry) to achieve your entire ventilation system design in one turnkey solution and save your operation costs and time.


    Made-In-House Ducts Supply

    A wide array of flame retardant ducts with custom choices standing by adapt to your actual operation ventilation, FREE SGS testing for your ventilation textile is available once you require it.


    Worry-Free Aftersales Service

    All ducts are guaranteed for 12 months. Free new products supplied if the original goods are damaged during delivery. On-site technical support is available if the ducting system gets ruined during operation.

    Professional Engineered Airflow Design

    Expertise decides the details of the ducting system while the software calculates the outline.


    Ventilation calculator based on SIA recommendation supported by our partner calculates the recommended duct diameter, fan size, and expected air pressure.

    All you need to do is to send a few parameters by clicks of the mouse, including

    • • Tunnel cross-section
    • • Tunnel length
    • • on-site(working temperature, altitude, etc)


    Duct diameter is not the only thing to consider when faced with the complex topography. An appropriate ducting system would lessen your operation costs based on normal ventilation, which requires various types of flexible duct to be included.

    • • Experience in serving over 3000+ clients from tunneling to hydraulic field
    • • A full ducting solution with specific types, shapes, angles, and lengths.

    Finished Product Quality Inspection


    Based on DIN53354 Standard or ASTM Standard (or other types of national standard), sampling fabric would undergo a grab test to meet customer requirement by in-house tensile strength tester.

    Inspectors set up related data and supervise the whole process step by step to get the result precisely.

    Approved Certificate

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    ISO9001 Certificate

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    ISO14001 Certificate


    SGS Test Report

    CE Duct

    CE Certificate

    Explore Our Projects

    Guangzhou Metro Project

    Guangzhou Metro Project - China

    We signed a partnership with Guangzhou Municipal Group Co., Ltd in 2016. We cooperated with underground projects on Guangzhou Metro projects and Tianhe Smart City Urban Corridor to successfully provide ventilation system design and ventilation ducts for these projects.

    PVC Ventilation Duct for TMCLK HongKong

    TMCLK Project - HongKong, China

    Tuen Mun-Chek Lap Kok link–Northern Connection Sub-Sea tunnel section, as Hong Kong’s deepest, longest and largest sub-sea road tunnel. We have supplied 2500mm diameter ventilation duct in the past years.

    Haolebaoji Jian Raiway Projects

    Haolebaoji-Ji'an Raiway Projects - China

    It is a new strategic corridor for “North-South Coal Transport” in China, with a total length of 1813.5 kilometers, and is the world ’s longest one-time heavy-duty railway built in one operation. We have supplied the 2200mm diameter semi-rigid duct and lay flat duct since 2016.

    Melbourne Metro Rail Project Sulong Vent Duct

    Melbourne Metro Rail Project - Australia

    The Melbourne Metro Rail Project involves the construction of a 9km-long tunnel within Melbourne, Australia, connecting the Sunbury and Dandenong railway route. Construction is scheduled to begin in late-2018 and operations are expected to start in 2025. We have have supplied the vent ducts of 1500mm diameter since 2019.

    Northconnex tunnel Project

    Northconnex Tunnel Project - Sydeny, Australia

    This project will be one of the longest road tunnels in Australia. The approx. 9km long double tube tunnel north of Sydney connects the M1 motorway near Wahroonga with the M2 motorway in West Pennant Hills, thus connecting the city’s north to the 110km long bypass known as the Orbital Network. This will bring relief to Pennant Hills Road, which is being used by more than 5,000 trucks per day. We have supplied 1800 dia lay flat duct and 2100 dia semi rigid duct since 2017.

    India Hydropower Project

    Mai-Beni Hydropower Project - Ilam, Nepal

    Located in the middle reach of Mai river in IIam district in eastern part of Nepal, Mai Beni Hydropower Projects is a runoff river type hydropower of 9.51MW. We have supplied 550mm diameter ventilation duct since 2019.

    Nepal Hydropower Project 01

    Solu Khola (Dudhkoshi) Hydropower - Solukhumbu, Nepal

    This project is an 86 KW Run of River type of project located at Solukhumbu District, Sagarmatha Zone, Nepal. We have supplied the 1100mm dia oval ventilation duct and 800mm dia lay flat duct for this project since 2019.

    Coal Mine Project of ventilaiton duct

    Vatukoula Gold Mine Projects - Fiji Island

    We have supplied our ventilation ducts and ventilation fans to Vatukoula Gold Mines since 2016, It is the owner of the largest producing gold mine in Fiji. Already operating for over 75 years, their mine has produced in excess of seven million ounces of gold.

    • Guangzhou Metro Project
    • PVC Ventilation Duct for TMCLK HongKong
    • Haolebaoji Jian Raiway Projects
    • Melbourne Metro Rail Project Sulong Vent Duct
    • Northconnex tunnel Project
    • India Hydropower Project
    • Nepal Hydropower Project 01
    • Coal Mine Project of ventilaiton duct

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