Mechanical/DT test for welder qualification-WQT/ASME

The mechanical/Destructive test (DT) for welder qualification test-WQT according to ASME SEC-IX.

Test specimen for welder qualification test (WQT), according to code BPVC ASME SEC-IX, here explains how many tests required for the welder qualification test (WQT), which depends on the varying thickness limit of the weld metal of the test coupon. here simplified table is given below with an explanation. 

Table QW-452.1(a)

Types and number of mechanical examination test specimens required.

WQT test specimen

NOTE

(1) To qualification of welder test WQT for qualify using positions 5G or 6G, the total number of tests required for the bend test is four. The welding qualification test (WQT), qualify using a combination of 2G and 5G in a single test coupon, a total of six bend specimens are required. see test Coupons in Pipe. The types of the bend test shall be based on the weld metal thickness.

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Welder (WQT) qualification thickness limit.

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(2) Coupons tested by face and root bends shall be limited to weld deposits made by one welder with one or two processes or two welders with one process each. Weld metal deposit by each and every welder and each process shall be present on the convex surfaces of the appropriate bent specimens.

(3) In the test specimen one face and one root bend test may be substituted for the two sides bend.

Explanation

* If the thickness of weld metal to the test coupon is less than 10 mm and after the successful compilation of the weld joint of the test coupon, the visual examination done according to ASME SEC-IX. QW-302.4 (which is given below). There are one face and root bend required for the mechanical test. And there is no side bend test required for under this condition.

* If the thickness of weld metal to the test coupon is from 10 mm to less than 19 mm and after the successful compilation of the weld joint of the test coupon, the visual examination will be done according to ASME SEC-IX. QW-302.4 (which is given below). There is two side bend required for the mechanical test with a note-3, and for face and root bend test see note-3 for the mechanical test.

* If the thickness of weld metal to the test coupon is from 19 mm to over, and after the successful compilation of the weld joint of the test coupon, the visual examination done according to ASME SEC-IX. QW-302.4 (which is given below). There is two side bend required for the mechanical test, and there is no test required for the face and root bend for the mechanical test.

Test Coupons in Pipe.

WQT test specimen positions 

For test coupons made on the pipe in the position of welding 1G or 2G of Figure QW-461.4, two specimens of the test coupon shall be removed as shown for the bend specimens in Figure QW-463.2(d) and Figure QW-463.2(e).

WQT bend specimens

WQT bend specimens

Omitting the specimens in the upper‐right and lower‐left quadrants, and replacing the root‐bend specimen in the upper‐left quadrant of Figure QW-463.2(d) with a face‐ bend specimen. For test coupons made on the pipe in position 5G or 6G of Figure QW-461.4, specimens shall be removed according to Figure QW-463.2(d) or Figure QW-463.2(e) and for all four specimens shall pass the mechanical test. For test coupons made in both positions 2G and 5G on a single pipe test coupon, specimens shall be removed according to Figure QW-463.2(f) or Figure QW-463.2(g).

2G and 5G on a single pipe test coupon

2G and 5G on a single pipe test coupon

GENERAL NOTE: When the side bend tests are made in accordance with the QW-452.1 and Table QW-452.3, they shall be removed as shown in Figure QW-463.2(g) in place of the face and root bends.

Welder

Except for the special requirements of the welder, each a welder who welds under the rules of the Code shall have passed the mechanical and visual examinations. Alternatively, welders may be qualified by volumetric Non-destructive examination (NDE) test, like Radiography, Ultrasonic Testing, Dye penetrant test, etc., When making a groove weld using Shielded metal arc welding (SMAW), Submerged arc welding, (SAW), Gas metal arc welding (GMAW), Gas tungsten arc welding (GTAW), Plasma arc welding (PAW), and except short‐circuiting mode for radiographic examinations or and a combination of these processes, except for pipe group number, P‐No. 21 through P‐No. 26, P‐No. 51 through P‐No. 53, and P‐No. 61 through P‐No. 62 metals. Welders making groove welds in P‐No. 21 through P‐No. 26 and P‐No. 51 through P‐No. 53 metals with the GTAW process may also be qualified by volumetric non-destructive examinations (NDE) test. 

A welder qualified to weld in according to one qualified Welding procedure specification (WPS) is also qualified to weld in accordance with other qualified WPS, using the same welding process, within the limits of the essential variables.

Visual examination of test coupon.

Welder/welding performance test coupons shall show no cracks and complete joint of the penetration with the complete fusion of the weld metal and base metal.