???? ????? UL/FM ???? ?????? ?????? ????? ?? ???????

??? ??????? ?????? ???? ??????? UL/FM ????? ???? ??? ???? ???? ?????? ?? ?????? ?????? ???? Shijiazhuang Deye Piping Industries Co., Ltd. ??? ?? ????? ??? ?????? ?????? ???????? ??????? ???? ?????? UL (Underwriters Laboratories) ?FM (Factory Mutual). ?????? ??????? ?? ???????? ??? ????? ?????? ??????? ?? ????? ??????? ?? ??????? ???????? ?????????? ????? ???? ??????? UL/FM ????? ??? ???? ??? ????? ?????? ???? ??? ???? ??????? ????? ???????? ?????? ?????? ?? ???? ?????? ?? ????? ??? ????? ??????. ??? ?????? ????? ?? ???? ????????? ??? ???? ??????? ??????? ????? ????????. ???????? ??? ???? ??? ???? ?????? ????? ?????? ??????? ????????? ?? ???????? ?????? ???? ???????? ??????? ????? ????? ??????? ??????? ??????? ?????? ??????? ????? ?? ???? ??????? UL/FM ????? ??? ???? ???? ?????? ???????. ??? ?????? ?????? ?? ???? ???????? ???? ????? ?? ??? ??????? ?????? ??????? ?? ???????? ??? ???? ???? ????? ????????