Some difference Between PEXB & PEXA

1. ProductionProcessDifference

(1) PE-XA refers to Peroxide Crosslinked ,presently in China, pexa pipe production line adopts Plunger/Ram type extruder like below photo.

• Line speed is very lower about 1.5mx2/min .
• The raw material is Powder type, before production, some additives like oxidant, crosslinking agent, etc, shall be mixed in advance.
• After 24 hours (at most 72 hours) running, the line has to be stopped, because the mouth die has to be coated by Teflon, shrinking film will be coated on the surface of the mandrel.

(2) PE-XB refers to Silicane Crosslinked, the PEXB Pipe production line adopts single screw extruder.

• Line speed is higher, speed can be up to 35m/min. Easy operation and control.
• Every time line stop, the screw must be cleaned off immediately.
• The Raw materials is Granule type, 95% Crafting materials+5% Catalyst master batch mixed before production .

2. PhysicalPerformanceDifference

PE-XA and PE-XB have similar chemical component, basic raw materials is same, but their physical performance has some difference.
(1) PE-XaisinitiatedinFranceat1950s.

• In order to keep the pipe lifespan at least 50 years, the crosslinked degree shall be more than 70%.
• Comparing PE-XB, the performance of high temperature-resistance, anti-aging, oxidation resistance is a little weaker.
• The pipe price of pexa is cheaper than pexb pipe.
• The thermal cofficient is 0.4w/m°C
• Oxidant Permeability (the lower the better) of pexa is lower than pexb

(2) PE-XbisinitiatedinEngland,German,Italyafterprocessmodificationat1960s.

• In order to keep the pipe lifespan at least 50 years, the crosslinked degree shall be more than 65%.
• Because PE-XB is three-dimensional crosslinked mode, the performance of high temperature-resistance, anti-aging, oxidation resistance is better than pexa
• The pipe price of pe-xb is a little expensive than pe-xa.
• The thermal cofficient is 0.42w/m°C
• Oxidant Permeability of pexb is higher than pexa.

3. FinalPipeDifference

(1) ColorMasterBatchadded

• PE-Xa pipe could not added any color masterbatch, it is pure color of raw material. ● PE-Xb pipe can add some color master batch during production .

(2) Flexibility

PE-Xa pipe is more flexible than PE-Xb, so during pipe line installation process, the bend performance is better than pexb.

4. EVOH/OxygenBarrierLayerEquipment

(1) ThreeLayers

• EVOH/PEXa pipe need two separate line, one for Pexa pipe first, the second is for EVOH/PExa, we called it two steps, working efficiency is lower
• EVOH/PEXb pipe can be co-extruded one step on one line, easy to operate .

(2) Fivelayers

• On the market now, only five layers PEXB/EVOH, presently not have Five Layers PEXA/EVOH.