A branch connection does not always require a separate tee fitting welded into the run tube. In a suitable application, collaring forms an outlet directly from the tube wall. The branch tube is then joined to that outlet using the method specified for the project.
What does collaring change?
Collaring forms the outlet from the run tube itself. It can remove the need for a separate tee fitting and some of its associated joints. The branch connection still needs to be completed and inspected according to the application requirements.
How is a branch outlet formed?
Start with the material, run tube diameter and wall thickness, branch diameter and required geometry. These determine the machine, tooling and pilot-hole preparation.
- Prepare the run tube. Establish the outlet position and prepare the opening required by the selected process.
- Form the collar. The tooling draws material from the tube wall into the branch outlet.
- Check the geometry. Verify outlet diameter, collar height, forming quality and workpiece requirements.
- Join the branch tube. Use the joining method specified for the project.
The sequence depends on the machine and application. One nominal diameter alone is not enough to select the process.
Collaring and a separate tee: a process comparison
A separate fitting
The process includes sourcing the tee, preparing the parts, fitting them together and making the required joints. Different fitting sizes also need purchasing and stock management.
An outlet formed from the run tube
A suitable application can use fewer separate components and fewer welds. Repetitive manifold production can also benefit from automated tube positioning and outlet forming.
When is collaring worth assessing?
- Manifolds or piping assemblies with multiple repeated branches.
- Significant fitting, preparation or welding costs.
- Repeat production where a stable cycle matters.
- A need to reduce the number of fitting variants held in stock.
- Plans to automate manifold or header production.
When can a conventional tee remain the better choice?
Material, diameter ratio, wall thickness, geometry, design requirements, applicable codes and the joining method can limit suitability. Very small batches may also favour a conventional solution.
Assess the actual workpiece
A drawing and process data are needed before proposing a replacement. Borderline geometries or demanding quality requirements may require a trial on the customer’s material.
Does collaring eliminate welding?
In many applications the branch tube is still welded to the formed collar. The potential saving comes from eliminating a separate tee and reducing the joining operations required by the complete assembly. It should be measured across the whole process.
How should the two options be compared?
Use the same workpiece and production volume. Include fitting cost, preparation, positioning, assembly, welding time, inspection and rework. Also consider stock, batch sizes, changeovers and the effect of automation on production flow.
How is a T-DRILL solution selected?
Selection depends on material, diameters, wall thickness, outlet geometry, output and the required level of automation. Explore T-DRILL collaring and the machine catalogue for the available process options.
A TEC-220 installation in Poland
See how INSS-POL introduced collaring into production.
Read the INSS-POL projectWhat should you send for assessment?
- Run tube outside diameter and wall thickness.
- Branch tube diameter and material grade.
- A drawing or workpiece model.
- Required geometry, tolerances and quality criteria.
- Design or code requirements and the joining method.
- Annual volume and batch sizes.
Have a tee connection or manifold to compare?
Send the current drawing. We will assess whether a formed outlet is a suitable option and whether a process trial is needed.
Common questions
Can every tee be replaced?
No. Suitability depends on the material, dimensions, wall thickness, geometry, design requirements and joining method.
Can a 1:1 branch be formed?
Feasibility depends on the actual diameter combination, material, wall thickness and required geometry. It needs technical verification.
Can a trial be arranged before purchase?
For new or borderline applications, qualification can include a trial using the customer’s material or workpiece where needed.
Technical source: T-DRILL collaring ↗. The applicable range and result are verified during selection and trials.