

Thesvin's metal frame non-woven fabric pre-filter is a coarse-stage air filter built around a split sub-frame and main-frame design, using polyester fibre media held in an aluminium, galvanised or plastic frame. It captures coarse dust, hair and fibres ahead of cooling coils, AHU sections and secondary filters, and is aimed at facility, HVAC and maintenance teams working in commercial air handling, pharmaceutical and food processing, automotive and machinery plants, energy and metallurgy sites, energy storage rooms, data centres and semiconductor facilities. Thesvin manufactures it in Zhongshan, Guangdong, China, in 46 mm, 69 mm and 96 mm thicknesses, with non-standard sizes made to drawing.
The part that matters first is how the filter sits in the host. This filter uses a sub-frame and main-frame arrangement: the filter element is carried in one frame that locates into the other, so the frame that seals and positions the filter in the duct or AHU track is separated from the frame that holds the media. From a fitment point of view, that means the structural frame can stay in service while the loaded section is changed, and dimensional wear is concentrated in the replaceable half rather than the mounting interface.
Frame material is selectable — aluminium profile, galvanised steel or plastic — so the interface can be matched to the track, holding clips or slide rails already present on the unit. Thickness options of 46 mm, 69 mm, 96 mm (roughly 2 in, 3 in and 4 in) cover the common track depths found on central air-conditioning pre-filter stages and fresh-air intakes. Standard face sizes of 594 × 289 mm, 594 × 492 mm and 594 × 594 mm are available in all three depths, and because the plant runs non-standard work, face dimensions and frame thickness can both be produced to your drawing.
The frame is the load-bearing element here. It is designed to hold shape under high wind pressure, so the media does not bow into the downstream coil or collapse against the fan side of an air handling unit. If you are replacing an existing filter, match the face size, the depth and the frame type first; efficiency grade and media come after the mechanical fit is confirmed.
The media is a high-toughness polyester fibre non-woven, selected for humid service. The filter is rated for continuous operation up to 50 °C and up to 100% relative humidity, which suits exhaust and ventilation paths where condensation and moisture loading are normal, and where a paper-frame or moisture-sensitive filter would lose rigidity. The polyester media is also flame-retardant.
Typical duty is pre-filtration: central air-conditioning pre-filters in factory workshops, high-humidity exhaust air, cleanroom fresh-air intakes and air handling unit inlets. In each case the job is the same — hold back the coarse load so the coil, the duct interior and any downstream finer filter see less dust. Because the frame and media are a durable assembly rather than a disposable cardboard panel, the replaceable section can be swapped without discarding the whole mounting structure, which is where the running-cost saving sits.
| Item | Detail |
|---|---|
| Product name | Metal double-frame primary filter (sub-frame and main-frame pre-filter) |
| Filter media | High-toughness polyester fibre, resistant to high humidity |
| Frame material | Aluminium profile, galvanised steel or plastic — selectable |
| Maximum operating temperature | 50 °C |
| Maximum operating relative humidity | 100% |
| Available depths | 46 mm, 69 mm, 96 mm (approximately 2 in, 3 in, 4 in) |
| Common standard sizes (W × H × D, mm) | 594 × 289 × 46 / 69 / 96; 594 × 492 × 46 / 69 / 96; 594 × 594 × 46 / 69 / 96 |
| Core applications | Central air-conditioning pre-filtration in factory workshops, high-humidity exhaust air, cleanroom fresh-air intakes, air handling units (AHU) |
| Customisation (OEM/ODM) | Non-standard sizes and frame thicknesses made to order; 50,000 m² plant and CNAS-accredited laboratory; ISO/IATF16949 certified |
Dimensional consistency is the core of a frame filter, so quality control starts there. Thesvin holds IATF16949 certification, obtained in 2024, alongside ISO 9001, ISO 14001 and ISO 45001. Incoming material is checked at IQC, frame and media assembly is monitored at IPQC, and finished filters pass OQC before packing — so the frame that arrives matches the drawing you approved.
The in-house laboratory is CNAS-accredited and can issue reports covering filtration efficiency, dust holding capacity and resistance. Production runs in a 50,000 m² plant in Zhongshan, Guangdong, China, which includes six cleanrooms totalling 20,000 m², with multiple automated lines and monthly output in the millions of pieces. Products meet REACH and RoHS requirements and compliance documents can be supplied. The company has more than 20 years of filtration development and manufacturing experience and has exported to Europe, the United States, Japan and South Korea for over 20 years, with more than 1,000 filter solutions developed to date.
To get a quote, send the device or vehicle model, the size or a drawing, the airflow or water flow at the filter position, the operating conditions (temperature, humidity, duty), and the quantity you expect to order. If no drawing exists, an old part or a measured photo is enough to start. Contact our team and we will come back with the fitment confirmation and price.
Fit depends on three things: face width and height, track depth, and frame type. This filter is offered in 46 mm, 69 mm, 96 mm depths and standard faces of 594 × 289 mm, 594 × 492 mm and 594 × 594 mm, in aluminium, galvanised or plastic frames. Send the unit model and measured dimensions and we will confirm the match before quoting.
Yes. An old filter or a clear photo with a tape measure across the face and depth is enough for us to read the interface dimensions. We then confirm the sub-frame and main-frame arrangement against your unit. Non-standard sizes and frame thicknesses are produced to order.
The polyester fibre non-woven is built for coarse pre-filtration ahead of coils and finer filters. It is rated for up to 50 °C and up to 100% relative humidity, and the media is flame-retardant. For a specific efficiency figure at your airflow, ask us for a laboratory report with the quotation.
The sub-frame carries the media while the main frame locates and seals the filter in the track. The loaded section is replaced and the mounting structure stays in service, so you are not discarding a full metal frame at every change. This lowers consumable cost over the filter's life.
Yes. OEM and ODM work covers non-standard face sizes, frame thicknesses and frame material, plus logo and packaging. Our plant is 50,000 m² with a CNAS-accredited laboratory, and we hold IATF16949 and ISO 9001 certification for dimensional control.
Standard sizes start at 500 pieces; custom sizes generally start at 1,000 pieces, negotiable by project. Regular orders run 15–25 days and custom orders 25–35 days. Confirm the quantity per size with your inquiry so we can schedule production.
Yes. For B2B buyers with a clear purchase intent we can supply standard-size samples free of charge, with international courier costs paid by the customer. Custom samples carry a small tooling charge that is refundable against volume production.
Replacement is driven by pressure drop and site dust load rather than a fixed calendar date. Check resistance across the filter at commissioning and set a change point; in dusty workshop or exhaust duty, inspect more often. The split-frame design means only the loaded section is swapped. Send us your operating conditions and we will advise on a change interval for your site.