ZY20 Small Diameter Precision Tube Mill Machine φ10-26mm Round Steel Pipe 90m/min HF Welding Line

Common Defects in Small-Diameter Thin-Wall Tube Welding

Tube makers running φ10–26mm precision lines report four recurring problems: edge wave and buckling on 0.4–1.5mm strip, drifting weld seams that leave incomplete fusion, ovality caused by uneven cooling, and cut-length drift on the flying saw. Each defect raises scrap and blocks precision, furniture and structural tube orders that demand tight tolerance and clean zinc coating.

Why Thin-Wall Small-Diameter Tube Fails During High-Speed Forming

Thin strip carries little rigidity, so any leveling or pass-geometry error is magnified before welding. A single-radius pass concentrates bending at the strip edge and triggers waviness, while a seam that is not positively guided drifts out of the squeeze-roll center, so the molten edges fail to fuse at speed. Weak roll shafts then wear and shift dimensions, and insufficient coolant releases residual heat that distorts roundness.

The ZY20 Small-Diameter Precision Tube Mill Solution

The ZY20 is built for φ10–26mm round tube at 0.4–1.5mm wall with a rated speed up to 90 m/min. A 7-roll precision leveler feeds the strip flat, then a double-radius pass design with 5-stand rough and 3-stand finish forming shapes the tube progressively to eliminate edge wave. Roll shafts in 42CrMo, quenched, tempered and high-frequency hardened, hold their profile over long campaigns.

At the weld point a dedicated seam guide locks the edges before squeeze rolls complete fusion, and an automatic outside-burr unit with pneumatic rapid in/out feed clears the bead. Spray plus overflow-pool cooling at ≥10 t/h stabilizes roundness before a 6-horizontal + 6-vertical sizing train and a 4-roll Turk head finish straightening ahead of the microcomputer flying saw, which cuts 4–8m lengths to ±3mm.

The line welds hot-rolled, cold-rolled and galvanized coil through a 100 kW solid-state HF welder, and protects tooling with overload couplings plus side-pull quick roll change. Each unit ships with layout and foundation drawings, on-site installation and commissioning, operator training and a one-year warranty.

Technical Specifications of the ZY20 Tube Mill

Where the ZY20 Precision Tube Line Is Applied

The ZY20 suits precision, furniture and structural tubing: table and chair frames, rack and display systems, handrail and balustrade components, automotive light-gauge parts, and thin-wall mechanical conduit. Its galvanized capability also covers light construction and greenhouse framing where the zinc coating must survive the weld zone with minimal rework.

How to Select the Right Small-Diameter Tube Mill

Confirm your diameter and wall window first — the ZY20 covers φ10–26mm and 0.4–1.5mm. Match speed to downstream demand (up to 90 m/min), then verify your material mix of HR, CR or galvanized coil so the welder power and cooling rating fit. Fix your cut-length range (4–8m, ±3mm) and roundness target, and review the layout and foundation drawings to size utilities before installation.

Frequently Asked Questions About the ZY20 Tube Mill

What diameter and wall range does the ZY20 produce?

φ10–φ26mm outside diameter and 0.4–1.5mm wall thickness, covering precision, furniture and structural small-bore tube in one line.

Can the ZY20 weld galvanized strip without burning the coating?

Yes. Positive seam guidance, adjustable squeeze pressure and ≥10 t/h spray/overflow cooling keep heat input at the seam narrow, so zinc burn-back stays minimal and controllable.

How quickly can rolls be changed between sizes?

Side-pull quick-change frames on the forming and sizing stands let operators swap roll sets without dismantling adjacent stands, sharply reducing changeover time versus fixed-shaft designs.

What does the turnkey service include?

Layout and foundation drawings, engineer-led installation and commissioning, operator training and a one-year warranty with spare-parts support.