With the increase of patronage of the whole metro network in Beijing, patronage at BJL4 and DXL increased as well especially at morning and evening peak hours. To meet the demand and improve service quality, BJMTR invested nearly RMB600 million to purchase 13 more trains and signaling equipment for them. Currently, T&C for 6 strains completed. These 6 trains will be put into the service fleet on Dec. 27. With the enlarged fleet, the headway of DXL at morning peak hours will be shortened from 4’ to 3’. This will improve the travel quality at DXL remarkably. People in Daxing will enjoy more convenient travel services.