If you are trying to track this approval loop then you should be using some kind of workflow program that has some kind of escalation ruling for those that do not respond quick enough. This is part of some PDM systems. I use workflow that is inside of SofTech's ProductCenter.
But I would look at your processes. You state that you have 5 or 6 individuals that you need response from. If this is replicating a signature then you may have too many signatures on your drawings. From all of the signatures on the drawing only one has legal implementations, that is the approving engineer's. If you were to go to court on a design, you are not going to bring the drafter, the checker, a quality person, a manufacturing person or any of the other individuals that sign the drawing other than the engineer who created the design or a supporting engineer (sometimes this ends up being the chief engineer on older projects). So the signature loop becomes very irrelevant.
If you are using the group of signatures for a checking loop then you should review this process also. Start by looking at your checking staff, why are they not catching these errors and continue from there. Drawing checking is a very intense responsibility and needs to be done diligently. Then go to the engineer.
If you are using the signature loop for a design check, you are too late in your processes to be doing this. This would require a design review loop in a meeting environment early in the project way before you would even start a drawing. And the signatures could be caught on a word document for the design review and not on the drawing.
If you are using the signature loop as a notification process then this should also be reviewed. On all of our projects we do a drawing review, kind of a final check on the drawings. All departments must send an individual to a meeting that can make decisions for the project and has the ability to implement them. These individuals can make suggestions to the engineer involved but do not sign the drawing. All individuals do sign a drawing review form stating that they were involved. All changes to the drawings stated in the meeting are taken as notes on the drawing review form prior to signing it.
I have 2 signatures on my drawings. One checker and one approving engineer. Here is a section of my manual that describes my checking and approvals.
Drawing checking includes ensuring that there are sufficient dimensions to allow the item to be fabricated. Included in this task is validating format, layout of the drawing and insuring that the notes on the drawing are in compliance with current standards. Design intent, method of dimensioning and note content is not part of the drawing checking process, the design engineer must support these activities and review content.
I want you to know that this environment is not easily setup. I had major support from my engineering manager who pushed this concept. So this really needs to start at the top of your organization. As you might have noticed I work at an ISO9001/2000 company and we have a large quantity of processes and procedures to support these activities. We do a lot of activities in a paperless fashion but not everything, yet. You have to take small steps to make this kid of a process work. I would start with a meeting that would review current process, a continuous improvement activity. Review portions of your processes and as a group decide what and when you want to work upon. Do not push implementation, get buy-in form all parties and then implement. Once again you will need a higher manager in the company to support these activities and to drive a solution that works for all parties involved. Not an easy task, but well worth it in the long run. Hope you luck. iQ