Tube: quoting round, square and rectangular tube

The Tube item quotes round, square or rectangular tube parts from dimensions, with no file: section, wall, length, end cuts (square or 45°) and round holes on each face (diameter and quantity). It is available from the Max plan and in the free trial; on Pro the item does not appear.

1. In Parameters › Tube, register the cutting speed by material and wall, with the pierce time, machine hour and minimum charge.
2. In Quotes, click + Tube.
3. Choose the material and section, then type the dimensions, wall, length, end cuts and the holes on each face.
4. Check the calculation line (cut, pierces, time and weight) and the unit price, which you can still edit.

How the calculation works

• Cut length: both ends (the section outline; at 45°, the outline of the angled cut) plus the outline of each hole.
• Pierces: one per end and one per hole.
• Time: cut length ÷ speed, plus pierces × pierce time, with the calibration factor.
• Weight: section area (outer minus inner) × length × material density. The price follows the laser item's rules: machine hour, minimum charge, setup, material per kg, taxes and the preset's margin.

Bar nesting

With Tube items in the quote, Bar nesting appears: enter the bar length (6000 mm to start) and the cut gap. Parts are grouped by material, section and wall and placed longest first; the screen shows how many bars and the leftover of each. A part longer than the bar shows as a warning.

Bar, chuck, common line and offcuts

• Bar: 6, 8 or 12 m with one click, or any length in the field.
• Chuck dead zone: the length the chuck holds (default 100 mm, 50 to 300 mm, in Parameters › Tube) is taken from the usable length of every bar.
• Common-line cut: straight-end parts of the same section sit together in the bar, with no cut gap, and the cut between them counts once in the cut length, the pierces and the price; the screen shows the saving.
• Offcuts: the store button writes off the offcuts used and stores in Parameters › Tube each leftover from the minimum up (default 500 mm), by material, section, dimensions and wall. The next nesting of the same profile uses the offcuts before new bars.

Rotation, micro-joints and internal weld seam

• Rotation in the bar: square at 0°, 90°, 180° or 270°; rectangular at 0° or 180°; round at any angle. It is stored with each part in the nesting.
• Micro-joints per part: add the time per micro-joint from Parameters › Tube (blank means zero). Kine does not draw a cutting path.
• Internal weld seam: the seam position (no reference, top, bottom, side or short text). It is for information only and does not change the price.

Open profiles: U, C, L, H and I

• In Section, choose U channel, C channel (lipped), angle (L), H beam or I beam. Dimensions: U — height, flange, web and flange thickness; C — height, flange, lip and thickness; L — leg A, leg B and thickness; H and I — height, flange width, web and flange thickness. A blank flange thickness equals the web.
• Area with sharp corners, without rolling or bending radius: U = h·tw + 2(b − tw)·tf; C = t·(h + 2(b − t) + 2(d − t)); L = t·(A + B − t); H, I = 2·b·tf + (h − 2tf)·tw. Weight per metre = area × density; a catalogue rolled profile, which has radii, weighs slightly more.
• End cut: the whole section outline, outside and inside; on a bevel, stretched in the cut direction (see End cuts). Holes: U, C, H and I on the web (face 1) and both flanges (faces 2 and 3); L on both legs.
• Speed: the Parameters › Tube row for the material and the larger thickness (web or flange). Bar nesting works as for tube, by material, profile and dimensions; rotation in the bar: U, C and L 0° only, H and I 0° or 180°. Common-line cutting and offcuts work the same.

3D file of the part (STEP and IGES)

• Instead of typing, click Open 3D file and choose a STEP (.stp, .step) or IGES (.igs, .iges) file. The file is read in the browser itself and is not sent to the server; the part shows up in 3D, to rotate and zoom.
• From a straight part, Kine recognizes the section (round, square, rectangular, U, C, L, H or I), the dimensions, the wall, the length, straight or 45° ends (closed tubes) and the holes and cutouts in the walls, with face, position, diameter or width × height. The fields are filled in and stay editable: check them before saving.
• The most repeated diameter on each face goes to that face; holes of another diameter and rectangular cutouts go to Other holes and cutouts, which you can also fill in by hand. Each one is added to the cut (π·d for round, 2·(width + height) for rectangular) and counts one pierce.
• Not recognized: curved or bent parts, solid bars, sections other than these eight and cutouts touching an end. In those cases a warning appears and you enter the dimensions by hand.

End cuts: bevel and saddle

• Each end (start and finish) has its own cut: square, bevel or saddle (fish-mouth). An older item with 45° ends opens as a 45° bevel on both ends, with the same math.
• Bevel: angle between the cut and the tube axis, from 15° to 90° (90° is square, 45° is a miter). On round tube the cut is an ellipse (Ramanujan's formula); on square, rectangular and open profiles, the faces the bevel crosses stretch by 1/sin of the angle. On rectangular and profiles, choose which measure the cut slopes across.
• Saddle: on round, square or rectangular tube, to fit onto another round tube of diameter D, with the axes at 90° (default) or from 30° to 90°. On square and rectangular tube, the side that touches the larger tube (on rectangular, choose which) must fit within D. The cut is the length of the curve where the two tubes meet, computed numerically. If it does not fit, a warning shows and no price is given.
• Each end cut goes into the cut length and the time; each end is still one pierce. With a bevel or saddle end, the item length is the overall length, tip to tip (the same the 3D file gives): that is what the part takes from the bar. The weight deducts what the ends remove (on a bevel, half the measure × cotangent of the angle, per end). Only parts with both ends square share a common-line cut.

Tube nesting

In Nesting, the Tube tab nests tube parts on their own, without opening a quote: add the parts (from the 3D file or by dimensions), choose the bar and the cut gap, and see the bars drawn, the leftover, the common line and the offcuts. Quote this nesting opens a new quote with the parts, each one's price and the same bar. The tab appears from the Max plan and in the free trial.

Special sections

Besides round, square and rectangular, the section can be oval (elliptical: width and height), obround (flat oval: two straights and two half-rounds), triangular (side), hexagonal (across flats) or D-shaped (flat base and half-round top: width and overall height). Perimeter and weight come from the real outline; bevel and saddle work on them too, with the touching side chosen.

Cutouts, joints and wall drawings

Other holes and cutouts takes round, rectangular, obround (slot) and tube joint — the hole where another round tube enters, with its Ø and the angle between the axes; on round tube the cut is the intersection curve, on a flat face it is the ellipse. Drawing on the wall takes a flattened DXF (logo, lettering, free cutout): the drawing's cut length and pierces go into the item.