... ,they are smooth,no stomatal trachoma and extend the steel rope' service life, Overview of YH series ... hardness type and hot-roll type ,among which ,the double-width board pressed type is patent product ... under stress with two point of support .Thus the entire puley is under steady stress.They have ... of D/1000 (D refers to the diameter of rope slot of the pulley),so they have high precisionNow , our ...