... , rubber hoses, cleaning ball and so on. Our technology: CHUNDA concrete pump pipe is quenched and carried out carburizing chemical treatment ... possess high wear-resistance. Characteristic: The inner hardness of CHUNDA concrete pump pipe can reach 60~65 HRC and the serving ... life can go to 35000-45000 cubic Certificate:Our concrete pump pipe has passed ISO 9001-2000,furthermore our supply ...