Cold Roll Forming Lines for C, Z and Omega Profiles

This range covers the lines we build around that process and the two directions they go in: open profiles such as C, Z and Ω purlins, and closed sections made by direct forming into square tube.

What Is Roll Forming?

Cold roll forming bends strip progressively through a series of passes at room temperature. There is no phase change and no melting — it is pure plastic deformation, which is why the two things that decide the result are the number of passes and the roll profile, together with the yield strength of the strip going in.

Cold Roll Forming Machine for C, Z and Omega PurlinsThere is no welding and no phase change — purely plastic deformation.See the line →Metal Roll FormingRoll forming is a cold process.See the line →Roll Forming Tooling & Die DesignOn the purlin line the roll body is bearing steel, hardened after machining, and the punch and cutter tooling is Cr12, also hardened.See the line →Roll Forming Line for SaleWhat to check before the money moves: forming route, tooling material, and the supply scope actually quoted.See the line →

That definition draws a line this range keeps: a roll-forming line shapes; a tube mill shapes and then welds. The purlin line works by cold forming with no welding: the profile is formed by roll bending plus hydraulic punching and cutting, which is the structural difference from the welded pipe lines we build.

Roll Forming Machines & Cold Roll Forming Lines — Range, Configuration and Output

The forming section is an 18-pass roll former with hydraulic punching and cutting. We build two configurations, and they are different machines rather than two settings of one.

Purlin forming. A semi-automatic C/Z interchangeable line that produces multiple purlin sizes from one set of tooling through stepless adjustment — changing size does not mean changing rolls. It punches, cuts and forms automatically, reaches a forming speed of 20 m/min, and works material 2–4 mm thick.

Direct forming square. A square and rectangular tube line built on a combined mould: one mould set produces different sizes, and a size change is a servo adjustment rather than a roll change. Finished section runs 30 × 30 mm to 500 × 500 mm with wall 1.5–13 mm by step.

Key Parameters: Size Range, Wall Thickness, Line Speed and Welder Power Band

Roll and tooling materials are: forming rolls in bearing steel, hardened after machining; dies and cutters in hardened Cr12. Material thickness, line speed and output are confirmed against your profile section, steel grade and finished length at quotation. Send us those three and we will state the figures.

• Purlin forming speed: up to 20 m/min.
• Purlin material thickness: 2–4 mm.
• Purlin forming passes: 18.
• Direct-forming square section: 30 × 30 – 500 × 500 mm, wall 1.5–13 mm by step.

Under-specified rolls or dies show up as poor profile edge lines, hole position drift and early blunting of the cutting edge.

How to Choose the Right Model

If the product is an open profile — C, Z or Ω purlin, or a similar cold-formed section — the purlin line is the one, and the decisive question is whether the size spread you run is inside what stepless adjustment covers, because that is what removes the roll change.

If the product is closed square or rectangular tube, direct forming is the relevant line, and the decisive question is how often you change size. Its advantage is aimed squarely at plants that switch specification frequently: a combined mould with servo adjustment instead of a roll change.

The choice is decided by what leaves the line, not by throughput.

Scope of Supply, Installation and Commissioning

Purlin tooling arrives with one set of dies and cutters; Cr12 dies and cutters can be supplied continuously as they are reground or replaced by punching count. Export packing is specified per item rather than generically: control cabinets, impeders and induction coils, forming rolls and cutting tools travel in moisture-protected wooden cases with a spare-parts pack, while heavy frames ship bare, braced on cradles with designated lifting points and rust protection.

Rolls and key wear parts are machined in-house on our own CNC equipment, which is the reason spare tooling stays available years after handover. The engineering team is twenty people averaging twenty years’ experience, and the production base is open to factory audit.

Who buys a cold forming line, and what they check

Buyers arrive here from two different directions.

A steel structure or PV mounting fabricator buys the purlin line, and their acceptance criteria are specific: whether changing size needs a roll change, how accurately holes are positioned, and forming speed.

A square tube maker running many specifications reaches the direct-forming line, and their pain point is the opposite of a capability question — it is the cost of switching: roll change time and roll consumption when specification changes are frequent.

That second pain point is a customer objection in its own right: whether a size change means a long stoppage. Our answer for the direct-forming line is a combined mould with servo adjustment, roll saving above 90 per cent, and quick mould change. One exception is worth stating: making 100 × 100 mm tube needs the upper roll on the final open stand changed.

Why Buyers Move to Roll Forming

Three things usually set the purchase off. Building a new plant and buying a first line sized to a target product; expanding capacity or upgrading automation on an existing plant; and entering a new product type, which for this family means square tube by direct forming.

Two switching triggers also land here. Slow changeover and high roll cost on existing equipment, which is exactly what the direct-forming route addresses; and after-sales failure at the previous supplier, where spares and rolls stopped arriving.

For the second, our answer is a supply answer rather than a performance one: rolls are machined in-house on our own CNC equipment, spare parts ship direct, and engineers can be dispatched to site.

Certification, and what each certificate actually covers

ISO 9001 is held under certificate number 18524Q11269R2S, issued by National Standard Integration (Beijing) Certification Co., Ltd. under IAF MLA and CNAS accreditation.

CE certificates are held from UDEM under three separate numbers, and each covers a different line type: welded pipe equipment under M.2022.206.C72171, cold roll forming equipment under M.2022.206.C72172, and slitting lines under M.2022.206.C72173. A fourth CE certificate for cold forming is held from Ente Certificazione Macchine in Italy under 0P250616.HTWTT37.

Each number can be checked at the issuing body rather than taken on trust, which is why we publish numbers and verification routes instead of certificate images.

An enterprise standard, Q/GYLTT01-2023 for HGF150 high-frequency welded pipe equipment, is published on the national enterprise-standard platform. High-Tech Enterprise certificate GR202413001148 is held. The Madrid international trademark for TENGTIAN is registered under number 1 707 606. The patent portfolio is 30 granted utility model patents, with 7 invention patents applied for.

Delivery, payment and after-sales

Lines are dismantled into units and shipped in containers: heavy frames braced bare on cradles with designated lifting points and rust protection, precision and wear items in moisture-protected wooden cases with a spare-parts pack. Delivery takes 50 to 90 days.

Installation and commissioning are part of the supply rather than a separate quotation, backed by on-site dispatch and round-the-clock online support. There is a single point of contact, with a response time of under one hour. Payment is staged — 30 per cent deposit, 70 per cent before shipment — with third-party escrow and multiple trade terms available.

Anonymised reference deliveries

Our lines are running in more than a dozen countries — mostly on construction tube, and also on fire-extinguisher tube, furniture tube and other sections. Delivery cards show region and model or size; commissioning dates are available on request.

The two lines side by side

What “cold forming” rules out on this range

Because the purlin line has no welding at all, two things that matter on a tube mill do not apply to it.

There is no welder power figure, because there is no welder. There is no weld seam to inspect, because there is no seam.

The direct-forming route in the buyer’s terms

The buyer’s pain point is simple: traditional welded pipe lines cost time and roll wear every time the specification changes. The direct-forming answer is a combined mould where the change is an adjustment rather than a roll swap. That gives roll saving above 90 per cent, and point contact reduces roll wear.

Against conventional round-then-square forming, the difference is fewer forming passes and less roll changing, with the core difference being the combined mould plus servo adjustment.

The buyer for it is a square tube plant switching between 30 × 30 and 500 × 500 mm frequently, whose acceptance criteria are changeover time, roll saving rate and tool life.

How the two lines differ

The two lines on this range answer different questions, and their strengths show it. The purlin line’s strengths are bearing-steel hardened rolls, Cr12 hardened dies and cutters, and stepless adjustment without a roll change. The direct-forming line’s strengths are one combined mould covering many sizes, roll saving above 90 per cent, and longer tool life.

Both lists are about tooling, but they are about different problems: the first is about holding accuracy in an open profile, the second about removing the roll change from a welded closed section. A buyer who reads them as competing claims will pick wrongly.

What both share is the supply answer behind them. Rolls and key wear parts are machined in-house on our own CNC equipment, which reduces reliance on outsourced tooling and is the reason lead time, cost and consistency stay controllable.

Send the profile drawing, material thickness and grade, and the size spread you expect to run. For the purlin line, add hole pitch and length range; for direct forming, add the square sizes and wall you need.

Die and cutter service lives in strokes or hours are available on request. Installation and commissioning scope at unit level is available on request.