Rectangular hollow sections are not as common as UCs and UBs. This is down to the fact that it is much more difficult to bolts it to other beams or to bolt other members to it. RHSs are described by their depth, width and wall thickness. An example is a 200 x 100 x 8 RHS, which is 200 mm deep, 100 mm wide and the wall is 8 mm thick. Hot rolled RHSs are made at the mill as one piece, whereas cold formed RHSs are made of a flat sheet rolled at right angles and welded. It is therefore easy to note the difference, as the cold rolled RHSs have a weld all along its length.

Standard	ASTM A500, EN 10210, EN 10219, JIS G3466, BS 1387, BS 6323 PART5
Grades	A500, S185, S235, S235JR, S235 G2H, S275, S275JR, S355JRH, S355J2H, St37, ST52
Out diameter	10*20mm - 600*400mm
Wall thickness	0.5mm - 20mm

Surface Conditions                                          Special Features

Hot Rolled                                                                Hard to find sizes

Hot Rolled Pickled and Oiled                              Mitre cutting
Cold Rolled                                                              High strength steel on request
KleenKote                                                                Mult lengths

Standard Corner Radius(Mechanical Sizes:)

Diameter (inch)	Wall Thickness (inch)	Radius Tolerance (inch)
1/2 to 1 1/2	0.028	1/32 to 1/16
1/2 to 2 1/2	0.035	1/32 to 1/16
1/2 to 4	0.049	3/64 to 5/64
1/2 to 4 1/8	0.065	1/16 to 7/64
3/4 to 4 1/8	0.083	5/64 to 1/8
over 4 1/8 to 6	0.095	3/16 to 5/16
1 to 4 1/8	0.095	3/32 to 5/32
over 4 1/8 to 6	0.109	3/16 to 5/16
1 1/4 to 4	0.109	1/8 to 13/64
over 4 to 6	0.120	3/16 to 5/16
1 1/4 to 4	0.120	3/16 to 5/16
over 4 to 6	0.134	7/32 to 7/16
2 to 4	0.148	3/16 to 5/16
over 4 to 8	0.148	7/32 to 7/16
2 to 8	0.165	1/4 to 1/2
2 to 8	0.180	1/4 to 1/2
2 1/2 to 4	0.203	5/16 to 9/16
over 4 to 8	0.203	5/16 to 9/16
2 1/2 to 8	0.220	3/8 to 5/8

Standard Corner Radius(Structural Sizes:)

Max. 3 x Nominal Wall Thickness

Mechanical Sizes		Structural Sizes
Largest Nominal Outside Dimension	Outside Tolerance at all Sides at Corners	Largest Nominal Outside Dimension	Outside Tolerance at all Sides at Corners
3/16 to 5/8	± 0.004	2 1/2 and under	± 0.020
over 5/8 to 1 1/8	± 0.005	over 2 1/2 to 3 1/2	± 0.020
over 1 1/8 to 1 1/2	± 0.006	over 3 1/2 to 5 1/2	± 0.030
over 1 1/2 to 2	± 0.008	over 5 1/2	± 1%
over 2 to 3	± 0.010
over 3 to 4	± 0.020
over 4 to 6	± 0.020
over 6 to 8	± 0.025

Straightness
Mechanical Sizes: Max. 1/16" in 3 feet
Structural Sizes: Max. 1/8" x Number of feet of total length divided by 5

Wall Thickness
Mechanical & Structural Sizes: ± 10% of Nominal Wall Thickness

Squareness of Sides
Mechanical Sizes: Max: ± b = c x 0.006"
                        b = Tolerance for out-of-square
                        c = Largest external dimension across flats
Structural Sizes: Adjacent sides may deviate from 90 ° by ± 2 °

Maximum Twist (Mechanical & Structural Sizes)

Largest Dimension, inches	Max. Twist*, inches
over 1/2 to 1 1/2	0.050
over 1 1/2 to 2 1/2	0.062
over 2 1/2 to 4	0.075
over 4 to 6	0.087
over 4 to 8	0.100

Convexity & Concavity(Mechanical & Structural Sizes)

Largest Nominal O.D., Inches	Tolerance ± Inches
2 1/2 and under	± 0.010
over 2 1/2 to 4	± 0.015
over 4 to 8	± 0.025

Structural Tubing A 500 Requirements

Grades	Chemical					Physical
	C Max. %	Mn Max. %Max. %	P Max. %	S Max. %	Cu Max. %	Tensile strength, min. psi	Yield strength, min. psi	Elongation in 2 in.
B	0.26	/	0.04	0.05	0.20	58,000	46,000	23
C	0.23	1.35	0.04	0.05	0.20	62,000	50,000	21

EN10210 S355NH Rectangular/Square steel pipe