How to Make a Flange on a Tube
– Step 1: Put on the nut
– Step 2: Insert the tube into the die
– Step 3: Place the clamp
– Step 4: Flare the tube hole
– Step 5: Finish the collar
– Step 6: Connect the tube
A flange is the end of a tube that is flattened outward. This flange forms the parting line for a special nut, which is threaded onto the tube beforehand. This nut is then screwed onto any thread compatible with it. This allows a copper tube to be quickly connected to various equipment: stopcock, flexible supply hose for a mixer, male plug, etc. It can also be a male fitting held by a collar made at the end of another tube. The sealing is ensured by a flat gasket (in fibre), and these screwed connections remain removable afterward.
The flanged collar is cold-formed with a specific material: a die and two pins (one conical and the other with a shoulder). These needles are either to be struck or to be screwed into a clamp.
Here is how to make a flange collar.
Note: copper sold in bar form (straight tube) is hardened and, therefore, very hard to shape. To obtain a flanged collar with this tube, you must first anneal its end over a few centimetres by heating it with a blowtorch.
1. Thread the nut
From the start, thread the nut that will be used to connect the tube onto the tube. Do not start with the flanged end.
2. Insert the tube into the die
– Orient the die with the chamfers (45° sloping surface to the top or bottom of a part) upwards.
– Place its jaws on either side of the tube and place the tube in the corresponding bore (calibrated hole).
– Extend the tube 3 to 4 millimetres above the bore.
Tighten the jaw nut(s) firmly to secure the tube.
Tip: If access is difficult (e.g., wall-mounted pipe), loosen the die nuts to separate the die jaws. Place one behind the pipe, which you can move slightly away from the wall after opening its clamps. Move the other jaw closer to the front and tighten their nut(s).
3. Place the bracket
If necessary, unscrew the shoulder pin a little to make it easier to engage the clamp on the die. Then position the needle over the tube hole.
4. Flare the tube hole
Screw in the conical pin to flare the tube hole. If the tube hole moves back, retighten the die nut(s).
5. Finish the flare
To finish forming the flare, loosen the taper pin and remove the clamp. Open the jaws of the die and turn it over.
– Insert the tube into the die with the flared end up. This part should rest around the corresponding bore.
– Lock the die around the tube.
– Replace the tapered needle with the one with the stepped end.
– Engage the clamp over the tube and screw the pin in to flatten the flared end of the tube and create the flanged collar.
Your flanged collar is cracked or misshapen? Cut the tube (with a tube cutter) and start again.
Note: beaded collars can also be purchased ready-made, in the form of small pieces with the usual diameters of copper tubes. No need for a die or a punch. But you must know the basics of soldering. Also, bring a soldering torch, a single gas flashlight, and some supplies (stripper, tin wire…). Or call a professional to get your plumbing job done.
6. Connect the tube
– If necessary, hold the nut under the flange.
– Place a new flat gasket (of the required diameter) on the flange, which is now at the bottom of the nut.
– Present the male fitting of the other pipe (or hose) and screw on the nut with your fingertips. If the two parts are correctly aligned, the screwing is done without problems.
– Tighten the nut firmly but not more (it is made of brass and, therefore, fragile). – When further tightening is impossible, use an open-end wrench on the nut.
– Place another open-end wrench on the flats of the male fitting to prevent it from turning.
– Turn the system on or off and check for leaks. If there are tiny drops around the nut, tighten it slightly. Always maintain the male coupling.
Materials needed to make collars
Copper pipe cutter