What closes a TDF or TDC joint
TDF (Transverse Duct Flange) and TDC (Transverse Duct Connector) are flanges rolled from the duct's own sheet, and SMACNA lists them as profiles T-25b and T-25a. The flange itself does not hold two duct ends together. Three consumables do that: a corner piece at each of the four corners, a gasket along the flange, and clips along the flange edge that lock the two mating flanges together. Our guide on the real difference between TDF and TDC covers the profiles; this page covers the parts you buy to finish them.
A shop that makes a lot of flanged duct uses these in volume, every week. That is why many shops order them with the machine and then reorder.
What we can supply
Taokron does not manufacture these consumables. We can supply them, either added to a machine order or as a separate shipment, and we quote them per order quantity.
| Item | Sizes we can supply | What to tell us |
|---|
| TDF flange corners | 25, 30, 35 | Flange height and profile you run, sheet gauge |
| TDC flange corners | 20 to 40 | Ribbed (A) or plain (B) flange, flange size, sheet gauge |
| Flange clips for TDF and TDC joints | Tell us the size you use | Profile, clip length, gauge |
For reference, the TDF flange former on our machine list rolls a 35 mm flange height, and the TDC flange former covers ribbed (A series) profiles of 20, 25, 30, 35 and 40 and plain (B series) profiles of 20, 25, 30 and 35. If you use a size, gauge or coating that is not listed here, tell us what you buy today and we will confirm what we can supply.
The corner must match the flange
A corner piece sits inside the flange profile, so it is made for one profile at one size. TDF and TDC have different shapes (the hem turns inward on TDF and outward on TDC), and each size within a family has its own corner. Practical rules:
- Order by profile and size, not by a general description. "35 TDF" and "35 TDC" are two different corners.
- For TDC, say whether your flange is the ribbed (A) or the plain (B) type.
- If you are unsure, send a photo of a flange end and a corner you use today. That settles it faster than a drawing.
- Tell us the sheet gauge, so we can confirm the corner suits it instead of guessing.
If your shop runs both profiles, see TDF vs TDC before you decide which one to standardise on, and TDF vs angle flange if you are weighing both against a bolted angle.
Corners by hand or by machine
Corners can be fitted into the four corners of the flange by hand or with a machine. Neither is wrong. It depends on how many joints you close.
- By hand. Suits low and medium volume. You need only the corners, the clips and basic hand tools.
- With a pneumatic corner mounting machine. The Pneumatic Corner Mounting / Corner Inserting Machine (model SBCC) handles material up to 1.5 mm and runs on 4 kW. It speeds up finishing when you close many joints a day.
- With an auto corner making machine. The Auto Corner Making Machine makes corner pieces from coil at 40 to 120 pieces per minute (blanking force 45 kN, width 96 to 104 mm, thickness 0.8 to 1.0 or 1.0 to 1.2 mm). A shop that wants to make its own corners looks at this one. You may still want clips and other sizes from us.
- Inline on an automatic line. On an auto duct line such as the SBAL-III or SBAL-V, the flange is formed as part of the coil-to-duct sequence, and the corners and clips are what you add at the joint. See the TDF flange former and TDC flange former pages for the single machines.
TDF cleats can also be cut on the TDF cleat cutting machine if you run one. Cleats and clips are not always the same part, so tell us which one your joint uses.
Why order corners and clips with the machine
- Almost no extra freight. Boxes of corners and clips fill the gaps in a machine container, so topping up costs very little more than the shipment you were already making.
- One supplier. The same team handles the machine, the flange profile and the consumables, so the corner you receive is matched to the flange the machine rolls.
- Consistent fit. When the flange former and the corners come from one conversation, you avoid the situation where each is right and they do not fit.
- Mixed orders welcome. TDF and TDC items, clips and other consumables can go in one shipment. If you only need consumables, we ship them on their own.
What to send us for a quote
- Which items: TDF corners, TDC corners, clips, or a mix
- The profile and size of each, and ribbed (A) or plain (B) for TDC
- The sheet gauge and material you run
- Roughly how many you use per month, or how many you want in this order
- Your destination port, and whether the order is going with a machine
We quote per order quantity and reply within 12 hours. Use the form below, email [email protected] or message us on WhatsApp at +61 435 074 994.
What to check on incoming corners and clips
Whoever supplies you, run a short check on every first shipment:
- Fit. Test a few corners on your own flange before you open the whole order. They should seat in the profile without forcing and without play.
- Consistency. Pull corners from different boxes and compare. Thickness and shape should match from box to box.
- Edges and coating. Look for burrs that cut hands and for damaged coating at bends and cut edges.
- Specification. Many specifications built on SMACNA call for bolted corners, with a minimum corner gauge and bolt size stated in the project documents. SMACNA drawings show flange clips 6 inches (152 mm) long, with a maximum spacing along the joint that tightens as duct pressure goes up. Requirements differ between editions, so check the edition your project specification names and tell us the values it gives.
Corners and clips are only part of the joint. For the gasket and sealant side, see our sealants and gaskets guide, and for the full jointing options see duct seam and joint types compared.
Working with Taokron
- Machines built since 1994 and supplied to 100+ countries, with 60+ patents, from an ISO 9001:2015 factory
- Machines are CE marked with a Declaration of Conformity
- Australian office in Box Hill North, VIC
- Replies within 12 hours by email at [email protected] or on WhatsApp at +61 435 074 994
Request a consumables quote →
FAQ
Do you make the corners and clips?
No. We can supply TDF corners, TDC corners and flange clips to duct shops, either with a machine order or as a separate shipment. Because the items are matched to your flange profile, tell us the profile, size and gauge you use and we confirm what we can supply before you order.
Which sizes can you supply?
TDF corners in 25, 30 and 35, and TDC corners from 20 to 40. For reference, our TDF flange former rolls a flange height of 35 mm, and the TDC flange former covers ribbed (A series) profiles of 20, 25, 30, 35 and 40 and plain (B series) profiles of 20, 25, 30 and 35. For clips and for any size, gauge or material not listed here, tell us what you use today.
Can I mix TDF and TDC items in one order?
Yes. Mixed orders are welcome, so you can combine TDF corners, TDC corners and clips in one shipment, and add other consumables or spares if you need them. We quote each item per order quantity.
Can the consumables travel in the same container as my machine?
Yes. If you are buying a machine from us, boxes of corners and clips can go into the same container, which adds almost nothing to the freight. If you only need consumables, we ship them separately. Either way, tell us your destination port when you ask for a quote.
Can I use TDC corners on a TDF flange, or the other way round?
Do not assume so. The two profiles are different shapes, and a corner is made for one profile and one size. Send us the profile and flange height or size you run, and a photo of a corner you use now if you have one, and we match it before anything ships.
Should I buy corners or a corner machine?
It depends on volume. A shop that closes a handful of joints a day usually puts corners in by hand. A shop with steady volume looks at a pneumatic corner mounting machine, and a shop that wants to make its own corners looks at an auto corner making machine. Tell us your monthly duct output and we can quote the corners alone or discuss a machine.
