[MW:3979] Need confirmation as per code

Dear Members / Friends   I need code reference regarding following                 Q.1: Client wants to weld pads without releasing water?                 Q.2:  Can weld without releasing water, if yes what problems will appear  in          future?                 Q.3:  If we can weld, what is the code / standard acceptance criteria?                          subcontractor filled water for Hydrotest without completing the welding of some pads(plate 9mm) & shoe supports       Materials as following 1.       Pipe Thickness is 23.83 mm 2.       Dia 18" 3.       Service : high pressure steam 4.       Design pressure/temperature is 53.4 bar/427C 5.       Test pressure is 148.2 Bar as per B31.3