You really can't export and import sales orders  but if all you want is to bring the orders from one company to another, you can copy the BKARINV.Bxx, BKARINVL.BXX and BKARDESC.BXX to the folder of the new company and rename to the same file name wth BYY instead of BXX where BXX and BYY are whatever your company codes are.  BXX might be just B if you started with the Default company.  Also need to be sure all the part numbers and customers are in the new company.  
 
Might be easier to delete the new company and start over, making the new company as a copy of the existing company and then clear out what you don't want to bring over.

I would think you could use the EDI import feature for this.
 
But I dont know how it works   Id like to know though.
 
 
JW