1. Definition

Welded pipe is a type of pipe that is manufactured by rolling a flat sheet of steel into a cylindrical shape and then welding the seam to form a pipe. The welding process can be done using various methods such as Electric Resistance Welding (ERW), Submerged Arc Welding (SAW), or Gas Tungsten Arc Welding (GTAW). Welded pipes are commonly used in various industries for the transportation of fluids and gases.

2. Manufacturing Process


Pipe for General Purposes
Standard Specification ASTM A 53 – Grade A,B
E.R.W. Steel Boiler and Superheater Tubes
Standard Specification ASTM A178- Grade A,C,D
E.R.W. Heat-Exchanger & Condenser Tubes
Standard Specification ASTM A214
E.R.W. Heat-Exchanger & Condenser Tubes
Standard Specification ASTM A252- Grade 1,2,3
Steel Tubes for Structural Purposes
Standard Specification ASTM A500- Grade A,B,C,D
Steel pipe for fire protection use
Standard Specification ASTM A795- Grade A,B
Line pipe
Standard Specification API 5L
Casing and Tubing
Standard Specification API 5CT

4. Inspection & Test Plan

No. Activity Description Documentation
1 Plate receipt inspection and Cross check
Plates Certificates
Mill Test Certificates EN10204. 3.1/ 3.2
2 WPS & PQR and Welding Operator,
Welder and Status
– Approved PQRs/WPSs,
– Welder & Welding operator qualification certificated/records
3 Check NDE Operator List & Status NDE Operator List
4 Check Procedure Approval  
5 Check Manufacturing Specification  
6 Check Fit-up and Tack Welding  
7 Welding & Visual Inspection Dimensional & Visual Inspection Report
8 Cold Calibration, Size Inspection Dimensional & VisualInspection Report
9 NDT Inspection NDT Report (MPI, UT, RT)
10 Repair & recheck of NDE repairs NDT Report
11 Production test Production test report
12 Marking Dimensional & Visual Inspection Report
13 Final Visual & Dimesional Inspection Dimensional & Visual Inspection Report
14 Packing  

5. What is HSTECH can offer?

– Origin: South of Korea
– Grade: Various, depend up on the demands.
– Delivery time: Up to project requirements
– Material Certificate: EN 1024 type 3.1 , 3.2
– Expediting service
– Document Control