Does anybody follow the requirements of preheating during rolling of vessel shell?
“7.3.1 Preheat
All base metals should be heated to a minimum of 300 °F (150 °C) during all welding, rolling, thermal cutting, and gouging operations (except during weld overlay, see 7.5.4). For butt welding and attachment welding, this preheat temperature should be maintained through the entire plate thickness for a distance of at least one plate thickness on either side of the weld but need not extend more than 4 in. (100 mm) in any direction from the edge of the weld.
The preheat temperature should be maintained until PWHT or DHT is performed in accordance with 7.3.2”.
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