TKY joints

By bsrajesh Date 10-27-2004 04:36

May I get an answer for the following situation.

A WPS was qualified as per AWS D1.1 for TKY joints. Qualification was done using standard pipe 8" Sch.80, 12.7mm thk minimum(fig.4.27) .This was impact tested at -20 degree celcius.

a. Can this wps be used for production TKY jts with thickness less than 12.7mm, with impact at -20 degree?

b. Can this wps be applied for a production TKY jonts with diameter less than 4" ?

Note :AS per fig 4.27 the minimum diameter and thickness of the test coupon are specifed ( ie., 6" min , 12 mm thk minimum , and 5 mm offset min) and supplimentary essential variabl list for CVN impact requirement limits the thickness qualified to 16 mm or the minimum thickness welded. Also as per table 4.2 min. dia. qualified shall be 4" if test has been made on standard size pipe 6" sch 120 or 8" sch 80

By ajoy

Date 10-28-2004 09:23

You already have an answer to your queries.

a. The minimum thickness qualified is 12.7 mm

b. The minimum diameter qualified is 100 mm nominal.

By bsrajesh Date 10-29-2004 04:25

What would be the test coupon requirement (6GR) for qualification of diameter less than 4" and thickness less than 12.7mm,when notch toughness is called for?

By ajoy

Date 10-30-2004 04:56

Standard test pipes as per D 1.1 are 2 inch sch. 80 or 3 inch sch. 40 for qualifying on pipe 3/4 inch through 4 inch nomnal dia.

The above will qualify a thickness range of 3 mm to 19 mm.