Vietnamese cement manufacturer Chinfon Haiphong has said it will invest an extra US$250m to expand its operations.  The investment will go to a 500,000 tons/year clinker grinding station in Hiep Phuoc Industrial Park in HCMC and a second production line at its existing factory in the northern port city of Haiphong, said general director Tony Liu. Speaking at a dealers' conference in HCMC on Monday, he said work on the clinker grinding station would start next year. Chinfon Haiphong is seeking permission for the new production line with an annual output capacity of 1.4Mt, he told the conference, which also saw the launch a new cement product, PCB40. The company took the occasion to commend 43 outstanding distributors nationwide and received ISO 9001:2000 and ISO 14001:1996 certificates from certification agency Quacert.  Chinfon Haiphong is a joint venture between Taiwan's Chinfon Vietnam Holding Co. with a 70% stake, Vietnam's Minh Duc Construction-Stone-Additives Co. (15.56%) and Vietnam National Cement Corp. (15.44%).  The venture, which was established in 1992, has an initial pledged investment capital of US$263.7 million.