Stroke-ignition stud welding with a ceramic ring is an arc welding process in accordance with EN ISO 14555, in which studs (typically Ø 3–25 mm) are welded to a base material. The ceramic ring shapes the weld pool, reduces spatter and protects the fusion zone – particularly for larger diameters (often from >10 mm).
Key facts at a glance
Key Values (Reference Values)
| Feature | Reference Value / Note |
|---|---|
| Stud Ø | approx. 3–25 mm |
| Current | up to approx. 3.000 A |
| Welding Time | up to approx. 3.000 ms |
| Polarity (typical) | Positive pole at workpiece |
| Ceramic Ferrule | Commonly used for studs >10 mm; Single use per weld |
| Quality Inspection | Visual inspection + Bend test (depending on requirements) |
Details of our welding technology
The process “Drawn arc stud welding” is used for studs of an approximate diameter of 3 to 25 mm, welding current up to 3.000 A and welding times up to 3.000 ms.
In general, the positive pole of the power-source is connected to the workpiece. The stud will be inserted into the chuck of the stud welding gun and positioned onto the workpiece, possibly by adding a ceramic ferrule.
Initiating the welding process: by means of a lifting mechanism, the stud will be lifted and at first an auxiliary arc (pilot arc) of a low current will be drawn. Then the main arc will be drawn between the tip of the stud and the workpiece. The main arc of a high amperage must be adjusted to the diameter of the stud. The cross sectional area of the stud and the opposite workpiece a partially melting.
After the lapse of the adjusted welding time, the stud is moved towards the work piece and both melting zones join tightly. The power-source turns off, the melting zone solidifies and cools down. If a ceramic ferrules was used, it will be removed afterwords.
Step 1
The stud is placed against the workpiece.
Step 2
The stud is lifted off, while current is flowing, thus creating an arc.
Step 3
The arc melts the surfaces of stud and workpiece.
Step 4
The stud is plunged into the weld pool.
Step 5
A cross-sectional joint is achived.
See the process in action
This video takes you through drawn arc stud welding with ceramic ferrule – step by step, straight from practice.
Ceramic ring vs. shielding gas (strike-on ignition) – a brief comparison
- The ceramic ring mechanically stabilises and shapes the weld pool and acts as a molten metal shield.
- Shielding gas protects the molten pool from oxidation and replaces the ceramic ring in suitable applications.
- Important: Ceramic ring and shielding gas bolts are not interchangeable (different ignition tip geometries).
- Rule of thumb: If the process runs stably with a ceramic ring, it is often the more robust choice on site; shielding gas requires clean gas delivery and suitable bolts.
Frequently asked questions about stud welding with a ceramic ring
For which stud diameters is the ceramic ring method typically used?
Typically, spark ignition with a ceramic ring is used for diameters of 3–25 mm. In practice, the ceramic ring is used particularly frequently for larger diameters (often from >10 mm), as it shapes the weld pool and reduces spatter.
What is the purpose of the ceramic ring?
The ceramic ring serves as a melt shield and shapes the weld pool. It promotes uniform bead formation and reduces spatter. It is used once per weld and removed after welding.
Can I also weld ceramic ring studs using gas shielding?
No. Ceramic ring studs and gas-shielded studs differ in design, particularly at the ignition tip. If the wrong combination is used, the welding result may deteriorate and defects often only become visible during the bending test.
What are typical defects in the ceramic ring process?
Typical defects include an uneven or incomplete weld bead, spatter and porosity. Common causes include the wrong type of ceramic ring, incorrect seating of the ring, contaminated surfaces or unsuitable parameters (current/time/stroke).
How do I check whether the joint is sound?
During operation, a thorough visual inspection after each weld is essential (check that the bead is closed all the way round and inspect the surface). Before starting series production and after any changes to the parameters, a test weld with a bend test should be carried out.
