U-bend steel tubes

Our U-Bend Manufacturing Center allows us to increase efficiency and reduce lead times, while maintaining the world-class quality for which we are known.
Sunny steel’s tubing and pipe are produced to dimensional tolerances and finish requirements of ASTM and ASME A179, A 249/SA 249, A 688/SA 688, and A 803/SA 803 specifications.

Check to see more information about U-bend pipes :

Feedwater Heater Tubes Standard:ASME SA556

Chemical Composition

Grade	C %	Si %	Mn %	P %	S %
B2	0.27 max	0.10 min	0.29-0.93	0.030 max	0.030 max
C2	0.30 max	0.10 min	0.29-1.06	0.030 max	0.030 max

Mechanical Properties

Grade	Tensile Strength MPA	Yield Strength MPA	Hardness HRB
B2	410 min	260 min	79 min
C2	480 min	280 min	89 min

Each U bend tube of our range is rigorously quality checked by our team of talented professionals on every stage of production to deliver the clients defect free best quality products. These U bend tubes can be custom designed in various diameters as per the requirements of our clients.

U-Bend Fabrication Tolerances

Item	Condition (when)	Tolercance
	Nominal bend radius ≤ 2 x nominal OD	less than or equal to 12%
Ovality	2 x nominal OD < Nominal bend radius ≤ 4 x nominal OD	less than or equal to 10%
	Nominal bend radius > 4 x nominal OD	less than or equal to 5%
	Nominal bend radius ≤ 2 x nominal OD	0.75 x nominal wall
Mimimum wall thickness	2 x nominal OD < Nominal bend radius ≤ 4 x nominal OD	0.8 x nominal wall
	Nominal bend radius > 4 x nominal OD	0.9 x nominal wall
	Nominal bend radius ≤ 8″ (200mm)	+/-3/64″(1mm)
Bending Radius	8″ (200mm) < Nominal bend radius ≤ 16″ (400mm)	+/-1/16″(1mm)
	Nominal bend radius >16″ (400mm)	+/-5/64″(1mm)
Disrance between legs		Max 1/16″(1.5mm)
Wall thinning of bending area		Max 17%
Difference between leg lengths at the ends	Leg length ≤ 16′ (4.88m)	+1/8″(3mm)
	Leg length > 16′ (4.88m)	+3/16″(5mm)
Deviation from plane of bend		≤ 3/16″(1.5mm)
Flattening on bend		≤ 10% nominal diameter
Straight leg length	≤5m	+1/8″(3mm)
	>5m	+3/16(5mm)
Total tube length including radius	≤6m	+3/16(5mm)
	>6m	+5/16″(8mm)

SA-450/SA-450M

OD In (mm)	+	–	WT In (mm)	+	–
<1(25.4)	0.10	0.10	≤1.1/2(38.1)	20%	0
1∼1.1/2(25.4∼38.1)	0.15	0.15	>1.1/2(38.1)	22%	0
>1.1/2∼<2(38.1∼50.8)	0.20	0.20
2∼<2.1/2(50.8∼63.5)	0.25	0.25
2.1/2∼<3(63.5∼76.2)	0.30	0.30
3∼4(76.2∼101.6)	0.38	0.38
>4∼7.1/2(101.6∼190.5)	0.38	0.64
>7.1/2∼9(190.5∼228.6)	0.38	1.14

Application:
Boilers, heat exchangers, super heaters, condensers

Production Standard, Grade, Steel No:
ASTM A688/A688M-Welded Austentic Steel Feedwater Heater Tubes.
ASTM A 312/213/269,DIN 17458/2462,BS3605/1,JIS, ASME SA556G3429/3459,ISO1129/2037/9329,GB/T14975/14976/13296 and so on.

Material:
TP304,TP304L,TP316,TP316L,TP321,TP310S,TP347H,TP316Ti, Carbon steel, alloys and so on.

Process:
The removal of beads is done as per standard specifications.
Bead is cold worked.
It is brought in level with the base metal.
Before heat treatment on tube mill, bead rolling is made in-line.
This will help in recrystallization of weld structure.
The weld structure will also homogenize faster in annealing process.

Length: unbending length or fix length
Mill test certificate: according to EN 10204 3.2
Packing: Wooden cases, bundle or plastic bags, plywood boxes
Oil-dip, Varnish, Passivation, Phosphating, Shot Blasting.