ASME IX preheat qualification

Date 02-22-2011 11:13

Am i right in thinking for SMAW, i can add a preheat of 100 deg C without having to requalify? (existing preheat procedure qualification was at ambient temperature)

many thanks
Mick

By js55

Date 02-22-2011 14:06

When you ask, "am I right" are you making the determination from QW-253?

By scrappywelds (***)

Date 02-23-2011 01:51

dont get me wrong but preheat is min. welding temp, as long as max interpass temp is not gone over it is all good.

By mickdale (*)

Date 02-23-2011 12:51

yes - was looking at QW-253
chart states QW - 406.3 supplementary essential (no impacts on contract) so i assume all is good.

thanks
Mick

By 3.2 Inspector (***)

Date 03-04-2011 04:30

ok....

'ow about this?

Your WPS states preheat of 200 degree C and interpass of 300 degree C
According to what I keep reading in this forum, when making (for example) layer 5 or 6 in joint your interpass must be between 200 and 300 degrees C, right?

Inspector Gadget then measure 205 degree C as 'interpass' and gives a green light to weld, I guess I am correct this far?
Where does Inspector Gadget measure this temperature? yeah, at the latest layer welded, right? or very close to - as it should.

How about the temperature 3 inches away from the groove, which temperature is the steel there?

3.2