
Flat Bar Steel for Ship Building: Purchasing Specification
| Requirement | What to specify |
|---|---|
| Grade and society | State the steel grade (for example A, B, D, E, AH32, DH32, EH32, FH32 or AH36) and the classification society that will certify it. |
| Size | Plate thickness × width × length, or section size (for example a bulb flat, flat bar or angle designation), in mm; number of pieces or total weight. |
| Condition | Supply condition as required (as rolled, controlled rolled, TMCP or normalised) and Z-quality (Z15, Z25 or Z35) if through-thickness properties are needed. |
| Surface | Blast cleaning to Sa 2.5 and shop primer of 15–35 µm, if required, as the plate page lists. |
| Marking | Manufacturer, heat and batch number, grade, size and the classification society stamp. |
| Documents | Mill test certificate and society certificate, with impact test results where the grade requires them. |
Flat Bar Sizes and Weights
| type | size(mm) | CSA (cm2) | weight(kg/m) | allowable deviation (mm) | |||
| b | t | r | b | t | |||
| 8×100 10×100 12×100 15×100 |
100 | 8 | ≤2.0 | 8.0 | 6.28 | ± 2.0 | ± 0.3 |
| 10 | 10.0 | 7.85 | |||||
| 12 | 12.0 | 9.42 | |||||
| 15 | ≤3.0 | 15.0 | 11.78 | ||||
| 8×120 10×120 15×120 |
120 | 8 | ≤2.0 | 9.6 | 7.54 | ||
| 10 | 12.0 | 9.42 | |||||
| 15 | ≤3.0 | 15.0 | 14.13 | ||||
| 10×150 12×150 15×150 20×150 25×150 30×150 |
150 | 10 | ≤2.0 | 15.0 | 11.78 | ||
| 12 | 18.0 | 14.13 | |||||
| 15 | ≤3.0 | 22.5 | 14.13 | ||||
| 20 | 30.0 | 23.55 | |||||
| 25 | ≤4.0 | 37.5 | 29.44 | ||||
| 30 | 45.0 | 35.33 | |||||
| 10×200 10×200 10×200 10×200 10×200 10×200 |
200 | 10 | ≤2.0 | 20.0 | 15.70 | ± 0.3 | ± 0.3 |
| 12 | 24.0 | 18.84 | |||||
| 15 | ≤3.0 | 30.0 | 23.55 | ||||
| 20 | 40.0 | 31.40 | |||||
| 25 | ≤4.0 | 50.0 | 39.25 | ||||
| 30 | 60.0 | 47.10 | |||||
| 10×250 12×250 15×250 20×250 25×250 30×250 |
250 | 10 | ≤2.0 | 25.0 | 19.63 | ||
| 12 | 30.0 | 23.55 | |||||
| 15 | ≤3.0 | 37.0 | 29.44 | ||||
| 20 | 50.0 | 39.25 | |||||
| 25 | ≤4.0 | 62.0 | 49.06 | ||||
| 30 | 75.0 | 58.88 | |||||
| 10×300 12×300 15×300 20×300 25×300 30×300 |
300 | 10 | ≤2.0 | 30.0 | 23.55 | ||
| 12 | 36.0 | 28.26 | |||||
| 15 | ≤3.0 | 45.0 | 35.33 | ||||
| 20 | 60.0 | 47.10 | |||||
| 25 | ≤4.0 | 75.0 | 58.88 | ||||
| 30 | 90.0 | 70.65 | |||||
| 10×350 12×350 15×350 20×350 25×350 30×350 |
350 | 10 | ≤2.0 | 35.0 | 27.48 | ± 0.4 | ± 0.3 |
| 12 | 42.0 | 32.97 | |||||
| 15 | ≤3.0 | 52.5 | 41.21 | ||||
| 20 | 70.0 | 54.95 | |||||
| 25 | ≤4.0 | 87.5 | 68.69 | ||||
| 30 | 105.0 | 82.43 | |||||
| 10×400 12×400 15×400 20×400 25×400 30×400 |
400 | 10 | ≤2.0 | 40.0 | 31.40 | ||
| 12 | 48.0 | 37.68 | |||||
| 15 | ≤3.0 | 60.0 | 47.10 | ||||
| 20 | 80.0 | 62.80 | |||||
| 25 | ≤4.0 | 100.0 | 78.50 | ||||
| 30 | 120.0 | 94.20 | |||||
| 10×450 12×450 15×450 20×450 25×450 30×450 |
450 | 10 | ≤2.0 | 45.0 | 35.33 | ||
| 12 | 54.0 | 42.39 | |||||
| 15 | ≤3.0 | 67.5 | 52.99 | ||||
| 20 | 90.0 | 70.65 | |||||
| 25 | ≤4.0 | 112.5 | 88.31 | ||||
| 30 | 135.0 | 105.98 | |||||
Reading the table: Each size is written as thickness × width, so 8 × 100 is 8 mm thick and 100 mm wide, matching the b (width) and t (thickness) columns. CSA is the cross-sectional area in cm², the weight is in kg/m, “≤” entries are maximum corner radii and “±” entries are allowable deviations in mm.
How the Four Ship Building Pages Differ
The four pages cover steel for ship building and oil platforms: classified plate in one page and three rolled section types, bulb flats, flat bars and angles, in the others. The plate page lists the grades by classification society; the section pages give size, weight and tolerance tables.
| Page | What it covers | Product form |
|---|---|---|
| PLATE | Plate sizes, standards and the classification society grade table | Plate, 3–180 mm thick |
| FLAT BULB | Bulb-flat size table with area, weight and allowable deviation | Section, 80 × 5 up to 430 × 20 |
| FLAT BAR (this page) | Flat-bar size table with area, weight and allowable deviation | Section, 8 × 100 up to 30 × 450 |
| ANGLE | Angle size table with section area and weight, and JIS G3192 tolerances | Section, L200 × 90 and larger |
State the grade, classification society and size on your enquiry; section sizes are listed as designations on the pages.
Related plates in this range
Applications for Flat Bar Steel for Ship Building
Typical uses include ship hulls and decks, oil platforms, and ship stiffeners and framing such as bulb flats, flat bars and angles. Tell us the load, temperature and service conditions so the right grade and thickness can be quoted.
Cutting, Fabrication and Welding
Champak Industries describes full and part plate/profile supply and a plasma-cutting service. Send drawings, quantities, tolerances and edge preparation for your parts. Shipbuilding plate and sections can be cut to size and shape to your drawings through our plasma-cutting and cutting services. Send the grade, society, size and quantity. Weld with consumables and a procedure approved by the classification society.
Testing, Inspection Documents and Traceability
| Requirement | What to identify in the order |
|---|---|
| Classification certificate | Society (ABS, BV, DNV, GL, KR, LR, NK or RINA, as the plate page lists) and certificate type |
| Mill test certificate | EN 10204 3.1 showing grade, heat number, chemistry and mechanical properties |
| Impact test | Charpy temperature and energy for the grade (A, B, D, E and the AH, DH, EH and FH grades) |
| Z-quality | Z15, Z25 or Z35 through-thickness test, if required |
| Traceability | Heat number and plate number marked on the material |
See the company’s Quality Policy for its published policy.
Source Flat Bar Steel for Ship Building from Champak Industries
Champak Industries’ company profile records its establishment in Mumbai in 1978 and its stockist, import and export activities. Flat Bar Steel for Ship Building can be requested together with other plates in the Ship Building Plates Lloyds A range.
What Determines the Quotation?
Grade and brand, thickness, plate size, quantity, cutting, testing and packing all affect the quotation. Say whether pricing is needed per kilogram, per plate or per finished piece.
Packing, Dispatch and Export Requirements
Give the delivery address, required date and unloading constraints. For export orders, include the destination port, delivery terms and document list.
Flat Bar Steel for Ship Building: Frequently Asked Questions
01What is Flat Bar Steel for Ship Building?
Flat bar steel for ship building is listed in sizes from 8 × 100 up to 30 × 450, with a table of section dimensions, cross-sectional area, weight per metre and allowable deviation.
02Which sizes does the page list?
Flat bars from 8 × 100 up to 30 × 450 mm, in widths from 100 to 450 mm, with several thicknesses for each width.
03How are the sizes written?
As thickness × width in mm, for example 8 × 100 is 8 mm thick and 100 mm wide.
04Which standard applies?
The page names no standard; state the standard and classification society on your enquiry.
05Can Flat bar be welded?
Yes; shipbuilding steels are made for welded construction. Use consumables and a procedure approved by the classification society, and follow the mill’s preheat advice for the grade and thickness.
06Which certificate should I request?
A mill test certificate (EN 10204 3.1) plus the classification society certificate, showing the grade, heat number, chemistry and mechanical properties and any impact test results.
07Can another grade replace Flat bar?
Shipbuilding grades are approved by classification societies; substitutions need the society’s agreement, so confirm any change with your surveyor or the society.
08Can Flat bar be cut to size?
Yes. Champak Industries lists a plasma-cutting service; send drawings, quantities and tolerances with your enquiry.
09Which sizes are available?
Availability depends on the grade, society and size; send the size you need and it will be confirmed at quotation.
10How do I get a price and delivery date?
Send the grade and society, size, quantity, destination and required date through the enquiry form below, by WhatsApp or by phone.