Bulb bars / flats are asymmetrical plate stiffeners for ships (Ship Hull, Ballast Tanks, Cargo Holds and like) & Bridges (Box& Plate Girder, Steel Decks and Expansion Joints &like) Construction work. These special profiles provide wide range of benefit as compared to conventional plate stiffeners used for the purpose. The benefits are available at the time of construction as well as during products (Ship / Bridge) life. The significant benefits prompted the designers / constructors to use these special profiles on increasing scales.

Benefits of using Bulb Bars

The benefits associated with the bulb bars which are considered to be tailor made for the envisaged application, over the conventional plate stiffeners like rolled sections / welded or fabricated stiffeners, are as follows

  • Ready to use
  • Maximizes resistance to buckling leading to increased   strength to weight ratio and saving in weight @ 40%
  • Easy access for welding and painting
  • Simplified collar connection
  • Reduced coating material and paining cost due to reduced surface area.
  • Reduction in time for cleaning of ballast tanks, cargo holds and like at Port   as foreign materials unlikely to get trapped in “Blind Corners” due to curved  & rounded profile.
  • Moisture and pollutants less likely to get trapped due to curved & rounded profile.
  • Welding is quicker and easy due to compact shape
  • Easy access for inspection.

Krishna Industries manufactures the bulb bars fulfilling the requirement of the below mentioned classification societies –
• Lloyds Register of Shipping
• Bureau Veritas
• American Bureau of Shipping
• Det Norke Veritas,
• Germnischer Lloyd,
• Nippon Kaiji Kyokai
• Russian Maritime Register of Shipping

Krishna Industries has manufactured Bulb bars in wide range of sizes and length as per GOST 21937 and supplied to Indian Navy over the last 5 years. Bulb bars of different sizes and length and of desire steel specification can be manufactured at our works to suit client’s requirements. The bulb bars have been produced at our works with following sizes.

BULB BAR NUMBER

WIDTH (b) mm

THICHNESS mm

HEIGHT
mm

SECTION WEIGHT kg/m

P5

50

4.0

16

2.25

P6

60

5.0

19

3.36

P7

70

5.0

21

3.98

P8

80

5.0

22

4.58

P9

90

5.5

24

5.52

P10

100

6.0

26

6.76

P12

120

6.5

30

8.75

P14a

140

7.0

33

11.05

P14b

140

9.0

35

13.23

P16a

160

8.0

36

14.08

P16b

160

10.0

38

16.60

P18a

180

9.0

40

17.41

P18b

180

11.0

42

20.24

P20a

200

10.0

44

21.47

P20b

200

12.0

46

24.60

P22a

220

11.0

48

25.75

P22b

220

13.0

50

29.20

P24a

240

12.0

52

30.42

P24b

240

14.0

54

34.18


Bulbbar_specs


STRAIGHTNESS VARIATION
Straightness tolerance q shall be 0.0035L (the entire length of the bar). Improved straightness tolerances may be available by agreement. Krishna Industries is in position to manufacture Bulb Bars conforming to European (EN), IS, GOST , Classification Societies like Lloyd,, ABS or any other specification as demanded by customer.

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