???? ??? ???? ???? ????? DN750 ?????? ????????? ????????

???? ??????? DN750 ?????? ?? ???? Shijiazhuang Deye Piping Industries Co.,Ltd. ?? ???? ???? ?????? ???? ?????? ?? ?????? ???? ????? ????? ?? ????? ????????? ????????. ????? ???? ??????? ??? ????? ???? ??? ???? ????? ????? ????? ?? ??????? ??? ???? ????? ??????? ???? ????? ?? ????? ?????? ??????? ???? ??????? DN750 ????? ?? ???? ?????? ??? ???? ?????? ?????? ?????? ???????? ??? ???? ????? ?????? ??? ?????? ?? ???? ?????? ?? ??????? ???????. ???? ????? ??? ?????? ???????? ?????? ??????? ??? ???? ????? ??????? ???????? ????? ??????? ?????? ??????? ??????? ??????? ??? ???? ??????? DN750 ????? ????????? ?? ?????? ????? ?? ????????? ??? ?? ??? ?????? ?????? ????????? ??????????? ????? ??????? ????? ?? ???. ?? ????? ??? ?????? ????? ???????? ???????? ??? ???? ???????? ???????? ?????? ???????? ???? ???? ??????? DN750 ?? ???? Shijiazhuang Deye Piping Industries Co.,Ltd. ?????? ?? ?????? ???? ????? ????? ?????? ?? ?????? ????????