ERW Pipes

ERW piping or Electric Resistance Welded pipe are used for many different applications, as it is the most readily available and economical type of mechanical tubing. There are two different types or processes to create ERW tubing. You have, CREW or Cold Rolled ERW and you have HREW or Hot Rolled ERW. With each type of Electric Resistance Welded pipe, there are different steps that go into creating the tubing, as well as different uses for each ERW tubing after it is created.

ERW pipe initially starts out as a flat pieces of steel, and then rolled into a tube shape. Without overlapping, the seam is then welded using a process called “Electric Resistance”.
HREW or Hot Rolled ERW is rolled at high temperatures. The high temperatures allow the HREW tubing to be formed easily.

ERW steel pipes are manufactured by Kalup Corp. with a range of 6 to16 inches for transmission of oil, gas, petrochemicals and water.


API 5L PSL2, IPS, IGS,AWWA-C200  to X70 Grade

Features of the production line:

Line speed: 8-30 m/min
Thickness: 4-10 mm
Output Diameter: 6-16 inch
Length: 3-15 m 

Linear Mass Table

Linear Mass(kg/m)
 OD(inch)  OD(mm)  Thickness(mm)
4.4  4.8  5.2  5.6  6.4  7.1  7.9  8.2  8.4  8.7  9.5  10
6 168.3 18 19 21 22 26 28 31 34 37
8 219.1 25 27 29 34 37 41 43 45 49
10 273.1 32 34 37 42 47 51 57 61
12 323.9 35 38 42 44 50 56 62 65 68 74 80
14 355.6 42 45 48 55 61 68 74 81 88
16 406.4 48 52 55 63 70 78 85 93 101


1.Forming Section :
This section includes the main machinery for producing pipes including coil processing, forming, resizing, and removing internal and external reinforcement, cutting and output line that are all provided by the Japanese company, KUSAKABE, which is one of the most popular companies in the field of designing and establishing pipe production manufactories internationally based on the latest technologies of the world.

2.Underground coil storage systems:

This type of coil storage system that was firstly developed and used by Kalup Co. is able to considerably increase the capacity of production line; compared to the usual storage devices called accumulator, this system does not need constant repair and enormous place for installation.

3.Rolling edge of sheet machine:
This machine is able to roll the edge of sheets and prepare them for optimal welding conditions based on API 5L PSL 2 standards.

4.Welding machine:

With the capacity of 500KW this machine is able to weld the prepared edge of sheets together in both CONTACT and INDUCTION modes.

5.Ultrasonic Thickness Measurement (UTM) Machine:

This machine is installed after the external weld stenciling machine and it is able to measure welding thickness and determines if the thickness is standard or not.

6.ON-LINE Ultrasonic testing machine:

This machine is able to detect the possible flaws in seam welding area and HAZ immediately after welding; thus it is able to immediately remove the defective pipe out of the production line.

7-Online UltrasonicTesting Machine:

This device enables the detection of possible defects in the weld and HAZ range immediately after welding, and therefore it will be able to immediately remove the defective pipe from the line.

8.Annealing machines:

Two annealing machines with overall power of 800KW can meet the requirements of API 5L PSL 2 standards.

9.Eddy-Current testing machine:

This device is able to detect the possible surface defects of seam welding after pipe cooling operation; thus it prevents defective pipes from entering the final operation area.

10.The final operation section:

Chamfering machine: This device chamfers the two ends of pipe based on the quality and tolerance determined in API %L PSL 2 standards.

11.Surfacing testing machine:

This machine flattens the samples extracted from produced pipes based on API 5L PSL 2 standards.

12.Hydrostatic testing machine:

This machine tests all produced pipes with maximum pressure of 5000PSI in hydrostatic mode.

13.OFF-LINE Ultrasonic testing machine:

channel ultrasonic testing machine is able to test seam welding of HAZ and also two ends of all produced pipes based on API 5L PSL 2 and to detect and mark out their possible defects.


14.Measuring section:

Appropriate space and facilities are provided for measuring weight and length of each produced pipe based on the requirements of API 5L PSL 2 standards.