SDBL Concrete Pump Twin Wall pipe Description concrete pump twin wall delivery pipe Hebei shengdebaolong can produce the best quality concrete pump twin wall delivery pipe, this kind of double layer pipe service life is longest , usually have boom pipe and deck pipe,have different thicknesses and lengthes. a.Product name: Concrete Pump Spare Parts - double layer pipe and tube b. Type:Concrete Pump Boom Pipe and deck pipe c. Thickness (outer pipe thickness+inner pipe thickness): 2+3mm, 2+3.5mm, 3+4mm and so on. d. Material: (1) Inner pipe is high chromium alloy steel ,outer pipe is alloy casted steel, this kind of twin wall pipe quality is equal to Conforms and Geramny Esser pipe, delivery capacity can reach 10000cbm, of course the price is highest. (2) Inner pipe is 65Mn, outer pipe is 20# steel , this kind of tube is our usual exported pipe , service life is 50000cbm-80000cbm, price is lower, this kind of pipe cost performance is good, exported to many countries  e.Service life: 50000cbm-100000cbm f.  Technoloy: this double layer tube inner wall pipe through heat treatment, also put one layer 20#pipe to protect the inner wall pipe, and then automatic welding the flange collar, Sand blasting, finally is Electrostatic spraying. g.Hardness: Inner wall pipe through heat treatment, hardness is about 65HRC. h.� Flange collar: SK flange, Zx flange, twin wall wear resistent flange, also HD flange collar. i. Color: red, blue, white, yellow, and so on. j. Application: usually twin wall boom pipe thickness is 4.5mm, 5.0mm, 5.5mm, usually used on the mobile pump And twin wall deck pipe is usually 7.0mm, this kind of pipe is usually used on the stationary pump.