UK Universal Beam Guide — UKB Sizes, Tata Steel Blue Book, S275/S355

Complete reference for UK Universal Beam (UKB) sections — the standard hot-rolled I-beam specified in British structural steelwork. Covers the full UKB range from 127x76x13 to the 1016x305x487 jumbo sections, design properties per the Tata Steel Blue Book, EN 10025-2 grades S275 and S355, and guidance on selection for typical UK building and industrial applications.

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UKB Designation System

UK Universal Beams follow a metric designation convention encoding the nominal section depth, flange width, and mass per metre:

Element Description Example
Nominal depth (mm) Overall section depth 457
Flange width (mm) Width of each flange 191
Mass per metre (kg/m) Self-weight 67
Section type UKB = UK Universal Beam UKB

Full designation: 457x191x67 UKB

Multiple mass options exist for some depth x width families — the 457x191 family includes 67, 74, 82, 89, and 98 kg/m. Heavier sections have thicker flanges and webs, providing greater bending and shear capacity.

Prior to metrication (pre-1970s), UK beams were designated in imperial: 18" x 7.5" x 55 lb/ft approximately corresponds to 457x191x82 UKB. The Tata Steel Blue Book includes imperial cross-references.


UKB Dimensional Range

Light and Medium UKB Sections (127 to 406 mm depth)

Designation Depth d (mm) Width b (mm) Web tw (mm) Flange tf (mm) Mass (kg/m) Iy (10^6 mm^4) Wel,y (10^3 mm^3) Wpl,y (10^3 mm^3)
127x76x13 127.0 76.0 4.0 7.6 13.0 4.73 74.5 84.7
152x89x16 152.4 88.7 4.5 7.7 16.0 8.34 109 124
178x102x19 177.8 101.2 4.8 7.9 19.0 13.6 153 175
203x102x23 203.2 101.8 5.4 9.3 23.1 21.0 207 236
203x133x25 203.2 133.2 5.7 7.8 25.0 23.4 224 258
203x133x30 206.8 133.9 6.4 9.6 30.0 28.8 279 319
254x102x22 254.0 101.6 5.7 6.8 22.0 28.4 224 259
254x102x25 257.2 101.9 6.0 8.4 25.2 34.2 266 307
254x102x28 260.4 102.2 6.3 10.0 28.3 40.0 308 354
254x146x31 251.4 146.1 6.0 8.6 31.1 44.1 351 401
254x146x37 256.0 146.4 6.3 10.9 37.0 55.3 432 492
254x146x43 259.6 147.3 7.2 12.7 43.0 65.3 503 573
305x102x25 304.8 101.6 5.8 7.0 24.8 44.4 291 336
305x102x28 308.7 101.8 6.0 8.8 28.2 53.5 347 400
305x102x33 312.7 102.4 6.6 10.8 33.0 64.6 413 476
305x127x37 304.4 123.4 7.1 10.7 37.0 71.4 469 538
305x127x42 307.2 124.3 8.0 12.1 41.9 81.4 530 607
305x127x48 311.0 125.3 9.0 14.0 48.0 94.9 611 700
305x165x40 303.4 165.0 6.0 10.2 40.3 84.8 559 634
305x165x46 306.6 165.7 6.7 11.8 46.1 98.2 641 729
305x165x54 310.4 166.9 7.9 13.7 54.0 116 747 851
356x127x33 349.0 125.4 6.0 8.5 33.1 81.5 467 536
356x127x39 353.4 126.0 6.6 10.7 39.1 101 570 652
356x171x45 351.4 171.1 7.0 9.7 45.0 120 686 779
356x171x51 355.0 171.5 7.4 11.5 51.0 142 798 906
356x171x57 358.0 172.2 8.1 13.0 57.0 160 895 1,020
356x171x67 363.4 173.2 9.1 15.7 67.1 194 1,070 1,220
406x140x39 398.0 141.8 6.4 8.6 39.0 124 626 718
406x140x46 403.2 142.2 6.8 11.2 46.0 156 775 886
406x178x54 402.6 177.7 7.7 10.9 54.1 186 925 1,050
406x178x60 406.4 177.9 7.9 12.8 60.1 215 1,060 1,200
406x178x67 409.4 178.8 8.8 14.3 67.1 242 1,190 1,350
406x178x74 412.8 179.5 9.5 16.0 74.2 272 1,320 1,500

Values are nominal from the Tata Steel Blue Book. Always verify critical properties against the current edition.

Deep UKB Sections (457 to 610 mm depth)

Designation Depth d (mm) Width b (mm) Web tw (mm) Flange tf (mm) Mass (kg/m) Iy (10^6 mm^4) Wel,y (10^3 mm^3) Wpl,y (10^3 mm^3)
457x152x52 449.8 152.4 7.6 10.9 52.3 214 952 1,090
457x152x60 454.6 152.9 8.1 13.3 59.8 258 1,140 1,300
457x152x67 458.0 153.8 9.0 15.0 67.2 289 1,260 1,440
457x152x74 462.0 154.4 9.6 17.0 74.2 333 1,440 1,630
457x152x82 465.8 155.3 10.5 18.9 82.1 371 1,590 1,810
457x191x67 453.4 189.9 8.5 12.7 67.1 294 1,300 1,470
457x191x74 457.0 190.4 9.0 14.5 74.3 333 1,460 1,660
457x191x82 460.0 191.3 9.9 16.0 82.0 371 1,610 1,840
457x191x89 463.4 191.9 10.5 17.7 89.3 410 1,770 2,020
457x191x98 467.2 192.8 11.4 19.6 98.3 457 1,960 2,230
533x210x82 528.3 208.8 9.6 13.2 82.2 475 1,800 2,060
533x210x92 533.1 209.3 10.1 15.6 92.1 552 2,070 2,370
533x210x101 536.7 210.0 10.8 17.4 101 615 2,290 2,630
533x210x109 539.5 210.8 11.6 18.8 109 669 2,480 2,840
533x210x122 544.5 211.9 12.7 21.3 122 762 2,800 3,200
610x229x101 602.6 227.6 10.5 14.8 101 757 2,510 2,880
610x229x113 607.6 228.2 11.1 17.3 113 873 2,870 3,290
610x229x125 612.2 229.0 11.9 19.6 125 986 3,220 3,680
610x229x140 617.2 230.2 13.1 22.1 140 1,120 3,630 4,150
610x305x149 612.4 304.8 11.8 19.7 149 1,260 4,110 4,660
610x305x179 620.2 307.1 14.1 23.6 179 1,530 4,940 5,640
610x305x238 635.8 311.4 18.4 31.4 238 2,090 6,570 7,540

Jumbo UKB Sections (686 to 1016 mm depth)

Designation Depth d (mm) Width b (mm) Web tw (mm) Flange tf (mm) Mass (kg/m) Iy (10^6 mm^4) Wel,y (10^3 mm^3) Wpl,y (10^3 mm^3)
686x254x125 677.9 253.0 11.7 16.2 125 1,170 3,460 3,980
686x254x140 683.5 253.7 12.4 19.0 140 1,360 3,990 4,570
686x254x152 687.5 254.5 13.2 21.0 152 1,500 4,370 5,000
686x254x170 692.9 255.8 14.5 23.7 170 1,700 4,910 5,630
762x267x134 750.0 264.4 12.0 15.5 134 1,500 4,010 4,630
762x267x147 754.0 265.2 12.8 17.5 147 1,680 4,460 5,140
762x267x173 762.2 266.7 14.3 21.6 173 2,050 5,370 6,170
762x267x197 769.8 268.0 15.6 25.4 197 2,400 6,230 7,130
838x292x176 834.9 291.7 14.0 18.8 176 2,460 5,890 6,800
838x292x194 840.7 292.4 14.7 21.7 194 2,790 6,640 7,630
838x292x226 850.9 293.8 16.1 26.8 226 3,390 7,970 9,120
914x305x201 903.0 303.3 15.1 20.2 201 3,260 7,220 8,390
914x305x224 910.4 304.1 15.9 23.9 224 3,760 8,270 9,560
914x305x253 918.4 305.5 17.3 27.9 253 4,360 9,500 11,000
914x305x289 926.6 307.7 19.5 32.0 289 5,040 10,900 12,600
1016x305x222 970.3 300.0 16.0 21.1 222 4,080 8,400 9,780
1016x305x249 980.1 300.0 16.5 26.0 249 4,810 9,810 11,400
1016x305x272 990.1 300.0 16.5 31.0 272 5,540 11,200 13,000
1016x305x314 1000.0 300.0 19.1 35.9 314 6,440 12,900 15,000
1016x305x349 1008.1 302.0 21.1 40.0 349 7,230 14,300 16,700
1016x305x393 1016.0 303.0 24.4 43.9 393 8,060 15,900 18,600
1016x305x438 1026.0 305.0 26.9 49.0 438 9,100 17,700 20,800
1016x305x487 1036.0 309.0 30.0 54.0 487 10,200 19,600 23,100

Jumbo sections are rolled in periodic campaigns. Lead times 12-16 weeks. Confirm availability before specifying.


Steel Grades: S275 and S355

UK Universal Beams are supplied to BS EN 10025-2:2019 in two principal steel grades:

Yield strength reduction with thickness

Thickness range fy for S275 (MPa) fy for S355 (MPa)
t <= 16 mm 275 355
16 < t <= 40 mm 265 345
40 < t <= 63 mm 255 335
63 < t <= 80 mm 245 325

Sub-grade selection

Sub-grade Charpy temp Typical application
S275JR +20 degC Internal steelwork, secondary members
S275J0 0 degC Enclosed structures, general building
S275J2 -20 degC External steelwork, cold climates
S355JR +20 degC Standard structural framing
S355J0 0 degC Most UK commercial buildings
S355J2 -20 degC Bridges, exposed structures, fatigue
S355J2W -20 degC Weathering steel (Corten equivalent)

Design to EN 1993-1-1

Partial factors (UK NA)

Resistance Symbol Value
Cross-section resistance gamma_M0 1.00
Member buckling gamma_M1 1.00
Tension fracture gamma_M2 1.10

Section classification

All standard UKB sections in S275 and S355 are Class 1 (plastic) or Class 2 (compact) for major-axis bending. The full plastic moment resistance Mpl,Rd can be developed before local buckling.

Flexural resistance (Class 1/2)

Mc,Rd = Wpl,y x fy / gamma_M0

Lateral-torsional buckling

For unbraced beams, the reduction factor chi_LT is per EN 1993-1-1 Clause 6.3.2.2. Most UKB sections have h/b > 2 and use buckling curve 'c'.


Typical Applications

Application Typical UKB range Span Key checks
Secondary beams (composite) 356x171 to 457x191 5-8 m Deflection, frequency
Primary beams 457x191 to 610x229 7-12 m Bending, LTB during construction
Transfer beams 610x305 to 914x305 8-14 m Bending, shear, web bearing
Portal frame rafters 406x178 to 533x210 15-30 m Combined actions, haunch design
Crane gantry girders 533x210 to 686x254 6-12 m Fatigue, lateral deflection
Stadia truss chords 610x305 to 914x305 15-25 m Axial + bending, buckling

UKB vs Other Section Types

Characteristic UKB UKC IPE HEA
Flange face Tapered Tapered Tapered Parallel
Depth/width ratio 2.0-3.5 ~1.0 1.5-2.5 1.0-1.3
Primary use Beams Columns Beams Columns
Standard BS 4-1 BS 4-1 EN 10365 EN 10365
Max mass (kg/m) 487 634 122 272

FAQ

What is the difference between UKB and UB sections?

UKB is the modern designation. Dimensional data is identical between old UB and current UKB designations for a given size. The prefix change distinguishes British-manufactured sections from imported UB sections.

What is the largest standard UKB?

The 1016x305x487 UKB (487 kg/m) rolled at Scunthorpe. Jumbo sections (914x305 and 1016x305 families) are rolled in periodic campaigns. Confirm availability with Tata Steel.

What grade should I specify?

S355J0 is the default for UK building frames. S355J2 for bridges, exposed steel, and fatigue-critical applications. S275 may be specified where deflection governs (increasing grade does not increase stiffness).

How do I specify a UKB on a drawing?

457x191x67 UKB - S355J2 to BS EN 10025-2:2019. Include section designation, type (UKB), grade and sub-grade, and the material standard.

Are UKB sections interchangeable with European IPE or HEA?

No. UKB has tapered flanges; IPE/HEA/HEB have parallel flanges. Dimensions and mass differ. Do not substitute without a full re-check.


References