HDPE liner reduces abrasion between sucker rod and tubing. Sealing system further reduces the corrosive failure.

HDPE liner reduces the friction coefficient between sucker rod and tubing. After adopting HDPE liner, the non-failure operational time related to the abrasion and corrosion between sucker rod and tubing increases by 400%. Under condition of not changing other design parameters, some of operational parameters, such as the load of sucker rod, balancing torque, Min stress of the bottom sucker rod string reduce greatly. The annual well operation frequency reduces from 4.3 to 0.59 after adopting the product.

Because of the low friction coefficient between HDPE liner and sucker rod, not only the polished rod load, gear reducer's output torque and Min. stress of bottom sucker rod string reduce greatly, but also the difference between maximum and minimum load of polished rod decreases obviously. The HDPE liner tubing reduces the energy consumption and increases the fatigue lifespan of sucker rod string obviously.

Corrosion, erosion, scale, rod wear, fatigue, pitting, embrittlement, all resulting from the very demanding