The polished rod is a critical component in sucker rod pumping systems, designed to transmit mechanical motion from the surface pumping unit to the downhole sucker rod string. It is manufactured from high-quality alloy steel, offering high tensile strength, a smooth surface, and an extended service life.
All polished rods are produced in strict accordance with API Spec 11B, ensuring high industry standards for durability, reliability, and performance in various well conditions.
Types of Polished Rods:
- Regular Grade D Polished Rod – Made from Grade D alloy steel, this type of polished rod is widely used due to its high strength and fatigue resistance. It is typically connected using a polished rod coupling to attach to the sucker rod string.
- End Upsetting Polished Rod – This rod features an enlarged end section, which allows for direct connection to the sucker rod without requiring additional couplings. This design reduces stress concentration at connection points, improving operational efficiency and longevity.
- Ultra-High Strength & Corrosion-Resistant Polished Rod – Designed for harsh well environments, this advanced polished rod is made of 20CrMo alloy steel. It undergoes quenching and tempering heat treatment to enhance its mechanical properties. Additionally, its surface is metal-sprayed with a nickel-based alloy (Ni35), significantly improving corrosion and wear resistance, making it ideal for highly corrosive, deep, or high-load well conditions.
✅ High Tensile Strength – Capable of withstanding extreme loads and ensuring stable pumping operations.
✅ Smooth Surface Finish – Minimizes friction and enhances sealing performance in stuffing boxes.
✅ Extended Service Life – Superior wear and fatigue resistance reduce maintenance costs and downtime.
✅ Corrosion Protection – Advanced Ni35 alloy coating resists H2S, CO2, and other corrosive elements.
✅ Enhanced Connection Strength – End-upset designs reduce breakage risk and improve reliability.
🔹 Oil wells with high mechanical loads
🔹 Corrosive environments with H2S, CO2, or brine
🔹 Deep well applications requiring high tensile strength
🔹 Heavy-duty artificial lift systems
Material Strength and Composition Tables
Regular Polished Rod Specification
| Item |
EPRR-01 |
EPRR-02 |
EPRR-03 |
| Size |
1-1/8" |
1-1/4" |
1-1/2" |
| Rod body diameter |
1-1/8" |
1-1/4" |
1-1/2" |
| Thread nominal diameter |
15/16" |
1-1/16" |
1-3/16" |
| With of sucker rod size |
5/8" |
3/4" |
7/8" |
| Vanish cone |
9° |
9° |
9° |
| Standard length |
25', 26' and 30' |
End Upsetting Polished Rod Specification
| Item |
EPRU-01 |
EPRU-02 |
EPRU-03 |
| Rod body diameter |
1" |
1-1/8" |
1-1/4" |
| Upsetting end thread nominal diameter |
1-3/16" |
1-3/8" |
1-9/16" |
| Non-upsetting end thread nominal diameter |
15/16" |
1-1/16" |
1-3/16" |
| With of sucker rod |
1-3/16" |
1-3/8" |
1-9/16" |
| Standard length |
25', 26' and 30' |
