Is there anything in any of the codes that disallows the welding of dogs and pullers onto pipe? If so please reference. My understanding that this is acceptable if done right at the bevel. However, why couldn't a welder weld dogs or pullers on 2 or 3 inches back from the bevel as long as the pipe was preheated and the welder was qualified and the proper rods were used and the dogs were removed when complete without damaging the pipe?