The key to Scunthorpe's form lies in their defence where skipper Andrew Crosby provides a solid base with Richard Hinds and Ian Baraclough adding excellent support.
Youngsters Andy Keogh and Billy Sharp were always focused on their business of keeping the Vale defence alert.
George Pilkington was a solid figure for Vale, while Billy Paynter and Nathan Lowndes worked tirelessly.
There was much early sparring with defences kept on their toes, Scunthorpe's Cleveland Taylor breaking through to half hit a shot which Pilkington headed clear.
In reply, Lowndes was given far too much space in midfield but he fired over from 25 yards.
Play quickly switched as Taylor's cross was header wide by Ian Baraclough and then Peter Beagrie twice tested the Valiants defence with teasing crosses.
The best effort of the game at this stage came in the 22nd minute when Steve Rowland fired in a 30-yard shot to force Paul Musselwhite into a good save.
From that point on Scunthorpe began to take charge with teenage midfielder Richard Ryan's left-foot shot flicked around the post by Mark Goodlad.
The home side were celebrating after 32 minutes when a great piece of football ended with Baraclough setting up Richard Hinds to drive home a low shot.
Five minutes later, the tormenting Beagrie cut in form the left and drove in a low ball which resulted in Keogh getting in a glancing header to put the Iron in a commanding position.
Beagrie might have added a third just after the break but he pulled his shot across the face of goal.
That seemed to signal a fight back by the Valiants and Paynter forced the former Vale keeper Musselwhite to punch away a shot destined for the top corner.
Musselwhite then denied substitute Christopher Birchall with another excellent stop, while in the final minute Sharp, yet to score in a home league game, saw Goodlad push away a cracking shot.