Database organization for mirroring / partitioning / multistore
Would service broker be an option? It can handle disconnected situations.
Use a local database on each PC ("clients") and one central database on the server. Each client sends Service Broker messages (XML files e.g.) to the server. For instance send information about an "action" from the production line.
Whenever the connection is lost, all messages are queued until you reconnect.
At the server you need to write a handler that processes these messages.