The short answer
To quote an ERW tube mill line or entry-section equipment (uncoiler, leveling machine, shear & butt welder, spiral accumulator), we need nine groups of information: (1) finished tube sizes — round OD × wall thickness and square or rectangular sides × wall thickness, including your largest size and the sizes you produce most; (2) steel grade with yield and tensile strength; (3) strip width and thickness ranges; (4) coil weight and coil inner and outer diameter; (5) target line speed; (6) local voltage and frequency; (7) cut length and cutting accuracy; (8) workshop size, crane capacity and whether pits can be dug; (9) your preferred trade term and destination port.
Prices are customized by configuration and quoted individually. There is no fixed price list, because the inputs above change the machines themselves.
You do not need every item before contacting us. Where data is missing, the quotation states the assumptions used, and the configuration is adjusted once the data is confirmed.
What each item decides
Each input fixes part of the line. The links below show why one missing value can change the configuration.
- Finished tube sizes → mill model, strip width, HF welding power and the number of roller sets. We select the smallest model that covers your largest OD and your largest wall thickness.
- Steel grade and strength (for example Q235, Q355 or high-strength steel) → the cylinder sizes of the leveling machine and the shear & butt welder. Each step up in strength or thickness moves these up a size, and with high-strength steel the mill may also need reinforcing. For very high-strength grades, the accumulator is also one size larger than the usual selection, and grades of 980 MPa and above are assessed separately from ordinary high-strength steel.
- Strip width and thickness ranges → the working width of every entry-section machine.
- Coil weight, inner and outer diameter → uncoiler capacity and type, and whether a coil car or an outboard support arm is needed.
- Line speed → accumulator size, main motor, HF power and run-out table length. The accumulator must hold enough strip to feed the mill for the whole coil-change and joining time, from the moment the uncoiler stops feeding until strip feeding restarts.
- Voltage and frequency → motors, electrical controls and purchased components.
- Cut length and accuracy → saw type and run-out table length. We offer a hot friction flying saw or a servo cold saw (which can be configured); the cold saw gives a cleaner cut and higher accuracy, and both options are priced separately.
- Workshop size, cranes and pit conditions → layout direction, foundation design and coil car type. The coil car is normally pit-mounted; where a pit cannot be dug, a floor-mounted version is used.
- Brand requirements and electrical specification → component selection. Brands of motors and electrical components can follow your specification.
- Project type (new line or upgrade) and planned timing → scope of the proposal.
- Trade term and destination port → the commercial basis stated in the quotation.
Worked example: from tube size to strip width
This is an example only, not a design. Suppose your largest product is a round tube Φ76 × 3.0 mm. In our standard catalogue range, YJ76 covers round OD Φ38.1–89 mm and wall thickness 0.8–3.5 mm, so this size falls within YJ76. Note that the maximum OD, wall thickness and speed are not a combination reached at the same time, square and rectangular tubes usually have a lower wall limit than round tubes, and parameters vary with configuration; the technical proposal is final.
Strip width can be roughly estimated from the outside perimeter (a theoretical value): OD × 3.14 for round tube, or the sum of the four sides for square and rectangular tube (mm). For Φ76: B ≈ 76 × 3.14 ≈ 239 mm. This is only for a rough idea; the actual strip width is set by the roller pass design and is usually slightly less, and it is confirmed by trial rolling for each new size.
Coil weight: uncoiler capacity is chosen from the actual coil weight, not from strip width alone, so please state your actual coil weight.
State the coil inner diameter too. The standard is Φ508 mm. If your coils are listed as 500 mm, the uncoiler expansion range must cover both 500 and 508 mm; if 610 mm coils must also be handled, the range is extended with spacer blocks or additional guide plates.
Adding entry-section equipment to an existing mill
Many projects add or replace a spiral accumulator, shear & butt welder or uncoiler in front of a mill that is already running, so coils can be changed without stopping the mill. For these inquiries, please also send:
- Your existing mill model and its pass line (center) height. Our entry-section equipment commonly works at a strip center height of about 900 mm (reference value); the difference is bridged by the accumulator's high turnover stand, with a two-roll pinch unit added after it where needed.
- Line hand: stand on the operator side and face the line. If the uncoiler is on your right, the line is right-handed; if it is on your left, it is left-handed. Layout drawings are made for the matching hand.
- The current line speed and the tube sizes you run.
- The floor length available from the uncoiler position to the mill entry, and whether pits can be dug.
- For single machines, whether the hydraulic power unit and electrical controls should be included. If you will supply the shear & butt welder yourself, tell us, and the layout drawing will leave a space for it.
Slitting line inquiries
A slitting line prepares strip of the required width for the tube mill. Please send:
- Material grade with yield and tensile strength.
- Mother coil width range, thickness range and the thickness you run most.
- Coil weight, coil inner and outer diameter, and the recoiler inner diameter you need.
- Number of strips and the narrowest strip width.
- Line speed, and whether pinch rolls and leveling are needed.
- Voltage and frequency, workshop size and pit conditions.
How the quotation is structured
Prices are customized by configuration and quoted individually. The quotation lists the equipment item by item — for example uncoiler, shear & butt welder, spiral accumulator, forming & sizing unit, HF welder, saw and run-out table — so you can check the scope line by line.
Two items are offered as alternatives so you can compare: the shear & butt welder (two or three of the grades integrated shear & manual welder, semi-automatic and fully automatic) and the saw (hot friction flying saw or servo cold saw). Line totals are given for the alternative configurations.
Rollers are not included in the line price. Each finished size needs its own roller set. Square and rectangular tubes can share the forming-section rollers of the round tube with the same perimeter and need only the sizing-section rollers, a so-called half set. Rollers are quoted separately and invoiced on actual weight: any overpayment is refunded and any shortfall is collected. Each size change also needs a matching set of roller bearings.
Equipment prices are ex-factory and do not include sea freight or installation, which are charged separately or as agreed in the contract.
Frequently asked questions
- Can you give me a price range first? Prices are customized by configuration and quoted individually. Sending the information above is the most reliable way to get a quotation you can actually compare and decide on.
- What is the minimum I must send? The equipment you are interested in and one way to contact you. Everything else can follow; the quotation states the assumptions used in the meantime.
- Can one line make all my sizes? One line covers the range of one model. Sizes from 1/2 inch (OD about 21 mm) to 4 inch (OD about 114 mm), for example, do not fit one model and should be split between two lines.
- Can you quote a mill for larger diameters? Yes. The large-diameter mills YJ-219, YJ-254 and YJ-273 are designed and built to order: an engineer designs each line for the specific order, and its parameters and configuration are set in that project's technical proposal. Send the same information listed above.
- Are rollers included in the line price? No. Rollers are quoted per size and settled on actual weight.
- Can I send drawings or specifications? Yes. Product specifications, your electrical specification and a workshop drawing all help. Send them by email using the address on our contact page.
About this article
Prepared by the InGen Engineering Team. This is a general technical guide. The formulas and examples are estimates for inquiry discussions, not a design basis or a promise of performance for any project; final parameters and configuration are set in the project's technical proposal and technical agreement.