he concrete pump straight pipe is made of special alloy steel ( 45Mn2). The inner pipe wall is case hardened by CNC high-frequency induction hardening machine. The inner pipe wall becomes a wearable layer with high hardness.  Specification of Concrete Pipe Type DN Thickness (mm) Length (mm) Weld-on Ends Weight (kgs) Applicable Pump Brands ST52 Seamless pipe 125 4.5 3000/ 2000/ 1000/ 500 148mm 46 PM,Schwing,Sany 7.0 148mm 72 PM,Schwing,Sany 45Mn2 Hardened Pipe 125 4.5 148mm Chrome Carbide Insert 48 PM,Schwing,Sany 7.0 148mm Chrome Carbide Insert 76 PM,Schwing Twin-Wall Pipe 125 2.5+2 148mm Chrome Carbide Insert 48 PM,Schwing,Sany 3.0+2 148mm Chrome Carbide Insert 53 PM,Schwing,Sany ZX-Pipe(ST52) 125