Untuk pengerjaan pipeline berdasarkan API 1104 dan juga project project oil and gas lainnya, maka para welder perlu di qualifikasi terlebig dahulu untuk menilai skill welder dalam melakukan welding nantinya.Setiap code yang digunakan pada umumnya telah memberikan aturan bagaimanacara mengkualifikasi seorang Welder. Di bawah ini tahapan dan requirement yang diperlukan untuk kualifikasi welder pipeline.
WELDER & WPS QUALIFICATION RANGE API 1104
A. A change from one welding process to another welding process , or combination of process, as follows :
1. A change from one welding process to a different welding process or,
2. A change in combination of welding process, unless the welder has qualified on separate qualification test, using or each welding process that are to be used for the combination of welding process.
B. A change in the direction of welding from vertical uphill to vertical downhill or vice versa
C. A change of filler metal classification from group 1 or 2 to group 3, or from group 3 to group 2 or 1 ( see table 1)
D. A change from one outside diameter group to another.These groups are defined as follows :
1. Outside dia less than 2.375 in (60.3 mm)
2. Outside dia from 2.375 in (60.3mm) through 12.75 I (323.9 mm)
3. Outside dia greater than 12. 75 in (323.9mm)
E. A change from wall thickness group to another.These group are defined as follows :
1. Nominal wall pipe thickness less than 0.188 in ( 4.8mm)
2. Nominal wall pipe thickness from 0.188 in ( 4.8mm) through 0.750 in (19.1 mm)
3. Nominal wall pipe thickness greater than 0.75 in ( 19.1 mm)
F. A change in the position from that for which the welder has already qualified (for example, a change from rolled to fixed or change from vertical to horizontal or vice versa). A welder who successfully pass butt-weld qualification test in the fixed position with the axis inclined 45° from the horizontal plane shall qualified to do butt-weld and lap fillet welds in all position.
G. A change in the joint design ( for example, the elimination of a backing strips or a change from V bevel to U bevel)