how can i getting quickly chinese visa ?

Dear Sir/Madam I am going to china before 6 time on F type. now strictly F type for china ? these days i have 1 shipment producing i want must go for inspection. i request to factory that is can not provide me invitation letter for local government. he say because i buy goods from factory first time goods. i have check travel agency that 45 days to i try but travel agency can not provide me. kindly tell me how can i getting quickly chinese type ?. Thanks