I understand your concerns. But actually in theory and in practice, no one can ensure the 100% penetration with one hundred percent certainty due to the workmanship of machines and workers. Also, welding seams would have more protection from rust if they are covered by sealant. Even CIMC factories try to speed the production line, but it is still in normal range. We hope Maersk can accept the way of sealing as all other clients have done with no problem