Bulb Flat Bar for Shipbuilding
Bulb flat bar for shipbuilding, also known as flat ingot steel, is a long, spherical or hemispherical metal material with a flattened end. Bulb flat bar for shipbuilding is typically made of carbon steel or steel alloys and features high strength and corrosion resistance. Depending on the processing method, bulb flat bar can be categorized into cold-drawn bulb flat bar, hot-rolled bulb flat bar, and forged bulb flat bar types.
Description
Bulb flat bar for shipbuilding, also known as Steel Bulb Flats, is a long, spherical or hemispherical metal material with a flattened end. Bulb Flat Bars for Shipbuilding are asymmetrical steel sections composed of a flat web and a spherical head, specifically designed for ship skeletons (skeleton/stiffening ribs). They possess high strength, good toughness, weldability, and corrosion resistance. The material is consistent with the matching ship plates (available in general strength grades such as A/B/D and high strength grades such as AH36/DH36).
Bulb flat bar for shipbuilding is typically made of carbon steel or steel alloys and features high strength and corrosion resistance.
Depending on the processing method, Bulb Flat Bar for Shipbuilding can be categorized into cold-drawn bulb flat bar, hot-rolled bulb flat bar, and forged bulb flat bar types.
Features of Bulb Flat Bars for Shipbuilding:
1. Unique Structure: The Bulb Flat Bar for Shipbuilding features an asymmetrical cross-section resembling a golf club (“ball head + web”), serving as a reinforcing rib for the hull frame and enhancing both local and overall rigidity.
2. Superior Mechanical Properties: The Bulb Flat Bar for Shipbuilding combines high strength (yield strength up to 355–690 MPa), good low-temperature impact toughness (e.g., impact energy ≥90–200 J at -40℃), and low sensitivity to weld cracking, making it suitable for harsh marine environments.
3. Material Matching to Ship Plates: The Bulb Flat Bar for Shipbuilding is designed to match ship plate grades according to classification society requirements (e.g., CCS A/B/D, AH32/36/DH36, etc.), ensuring structural integrity and certification compliance.
4. Diverse Specifications but High Customization Potential: Bulb Flat Bars for Shipbuilding have nominal widths of 80–430 mm (8–43), with each specification offering 2–5 different web thicknesses. Standard lengths are typically 6–16 m. Production is done in small batches with numerous specifications, requiring specialized roll forming mills.
5. Key Applications: Bulb Flat Bars for Shipbuilding are widely used in the main structures of cargo ships, cruise ships, container ships, and offshore platforms, including hull sides, decks, and bulkheads, replacing or supplementing T-sections. They are preferred for European ship types; angle steel is more commonly used in Japanese and Korean vessels.
Applications of Bulb flat bar for shipbuilding:
Bulb flat bar for shipbuilding is an indispensable raw material in shipbuilding. It is primarily used in the manufacture of hull cladding, reinforcements, connectors, and decks.
Because ships encounter complex climatic and marine conditions in the ocean, high-strength, corrosion-resistant materials are required to ensure hull strength and durability.
Bulb flat bar is widely used in the shipbuilding industry because of its high strength and resistance to corrosion when exposed to seawater.
Specifications of Bulb Flat Bar:
|
Model Number
|
Nominal Size (mm)
|
Theoretical Weight (Kg/m)
|
||||
|
b
|
t
|
h
|
r1
|
r
|
||
|
80X5
|
80
|
5
|
19
|
4
|
≤1.5
|
4.25
|
|
80X6
|
6
|
20
|
≤2
|
4.88
|
||
|
100X7
|
100
|
7
|
22.5
|
4.5
|
≤2
|
6.86
|
|
100X8
|
8
|
23.5
|
7.65
|
|||
|
120X6
|
120
|
6
|
23
|
5
|
≤2
|
7.32
|
|
120X7
|
7
|
24
|
8.26
|
|||
|
120X8
|
8
|
25
|
9.2
|
|||
|
140X7
|
140
|
7
|
26
|
5.5
|
≤2
|
9.75
|
|
140X8
|
8
|
27
|
10.85
|
|||
|
140X10
|
10
|
29
|
≤3
|
13.05
|
||
|
160X7
|
160
|
7
|
29
|
6
|
≤2
|
11.46
|
|
160X8
|
8
|
30
|
12.72
|
|||
|
160X9
|
9
|
31
|
13.97
|
|||
|
160X11
|
11
|
33
|
≤3
|
16.49
|
||
|
180X8
|
180
|
8
|
33
|
7
|
≤2
|
14.8
|
|
180X9
|
9
|
34
|
16.22
|
|||
|
180X10
|
10
|
35
|
≤3
|
17.63
|
||
|
180X11
|
11
|
36
|
19.04
|
|||
|
200X9
|
200
|
9
|
37
|
8
|
≤2
|
18.57
|
|
200X10
|
10
|
38
|
≤3
|
20.14
|
||
|
200X11
|
11
|
39
|
21.71
|
|||
|
200X12
|
12
|
40
|
23.28
|
|||
|
220X10
|
220
|
10
|
41
|
9
|
≤3
|
22.27
|
|
220X11
|
11
|
42
|
24.5
|
|||
|
220X12
|
12
|
43
|
26.22
|
|||
|
240X10
|
240
|
10
|
40
|
10
|
≤3
|
25.5
|
|
240X11
|
11
|
45
|
27.39
|
|||
|
240X12
|
12
|
46
|
29.27
|
|||
|
260X10
|
260
|
10
|
47
|
11
|
≤3
|
28.25
|
|
260X11
|
11
|
48
|
30.39
|
|||
|
260X12
|
12
|
49
|
32.43
|
|||
|
280X10
|
280
|
11
|
51
|
12
|
≤3
|
33.5
|
|
280X11
|
12
|
52
|
35.7
|
|||
|
280X12
|
13
|
53
|
37.9
|
|||
|
300X11
|
300
|
11
|
54
|
13
|
≤3
|
36.7
|
|
300X12
|
12
|
55
|
39.09
|
|||
|
300X13
|
13
|
56
|
41.44
|
|||
|
320X12
|
320
|
12
|
58
|
14
|
≤3
|
42.6
|
|
320X13
|
13
|
59
|
45.09
|
|||
|
320X14
|
14
|
60
|
≤4
|
47.6
|
||
|
340X12
|
340
|
12
|
61
|
15
|
≤3
|
46.2
|
|
340X13
|
13
|
62
|
48.86
|
|||
|
340X14
|
14
|
63
|
≤4
|
51.5
|
||
|
370X13
|
370
|
13
|
66.5
|
≤3
|
54.7
|
|
|
370×14
|
14
|
67.5
|
16.5
|
≤4
|
57.6
|
|
|
370×15
|
15
|
68.5
|
16.5
|
≤4
|
60.5
|
|
|
400×14
|
400
|
14
|
72
|
18
|
≤4
|
48.86
|
|
400×15
|
15
|
73
|
18
|
51.5
|
||
|
400×16
|
16
|
74
|
18
|
54.7
|
||
|
430×14
|
430
|
14
|
76.5
|
19.5
|
≤4
|
70.6
|
|
430×15
|
15
|
77.5
|
19.5
|
73.9
|
||
|
430×17
|
17
|
79.5
|
19.5
|
80.7
|
||
|
430×19
|
19
|
81.5
|
19.5
|
87.4
|
||
|
430×20
|
20
|
82.5
|
19.5
|
90.8
|
||
Standards and Classifications
| Size(mm) | HP80-HP430 |
| Standard: | EN10067:1997 |
| Grade: | A,B,D,E,AH32,AH36,DH32,DH36,EH32,EH36 |
| S235JR, S235J0, S235J2 | |
| S275JR, S275J0, S275J2 | |
| S355JR, S355J0, S355J2, S355K2 | |
| Certification: | ABS, CCS,LR,KR,NK,RINA,BV,DNV-GL,RMRS |
| CE Certification | |
| Length: | 6m-20m, according to customer’s request |
| Application: | Hull Structure , Bridge Structure, Offshore Platform |
Product Display
Packing & Delivery
Shipping By Sea
1. Standard packaging
2. Packaging according to customer requirements
