Strong API Sucker Rods

The consistently high quality of Sovonex™ sucker rods is the result of an advanced manufacturing process combined with a stringent inspection plan.

Production is fully automated to achieve the lowest tolerances and eliminate any single point of failure. Bars are normalized and tempered over their full length, thus relieving stresses and increasing the toughness of the steel.

Our multistage NDT regime covers the threads, connections and sucker rod body further and makes sure that each joint leaving our facility is up to standard.

Standard API sucker rods are available in several steel grades each with its own set of properties and field of application:

Grade C: For light to medium load applications in wells that are sufficiently protected against corrosion.

• Minimum yield: 414 MPa (60,000 psi)
• Tensile range: 621-793 MPa (90,000-115,000 psi)

Grade K: For light to medium load applications in corrosive environments. However, to prolong service life, we recommend to sufficiently protect against corrosion.

• Minimum yield: 414 MPa (60,000 psi)
• Tensile range: 621-793 MPa (90,000-115,000 psi)

Grade D: For medium to heavy load applications in wells that are sufficiently protected against corrosion.

• Minimum yield: 586 MPa (115,000 psi)
• Tensile range: 793-965 MPa （115,000-140,000 psi)

Grade D special: Combines the properties of grade K and grade D carbon sucker rods. For medium to heavy load applications in corrosive environments. However, to prolong service life, we recommend to sufficiently protect against corrosion.

• Minimum yield: 586 MPa (115,000 psi)
• Tensile range: 793-965 MPa (115,000-140,000 psi)

In corrosive wells, the service life of the API grade sucker rods is significantly reduced, resulting in high service fees and non-productive time (NPD).

To limit the negative effects of corrosion, we introduced a special surface finish that effectively shields sucker rod against any corrosive fluids or gases.

Each rod is tungsten alloy electroplated over its full length, giving it a strong and stable coating with a surface hardness of 57 HRC-60 HRC.

The protective layer effectively protects the sucker rod against abrasion and corrosion. Hydrogen embrittlement that weakens the rod string is no problem anymore.

In very deep wells or when running large capacity pumps, the increased load often is too high for standard API grade sucker rods.

Sovonex™ high strength sucker rods are specially developed to overcome this problem. Made from high-grade steel with a maximum tensile strength of 1,195 MPa（173,339 psi) and a minimum yield of 795 MPa (115,000 psi), these premium rods are well suited for extra heavy load applications.

The following premium sucker rods are available:

• High Strength (HS): For heavy to extra heavy load applications.
• High Strength Hardened (HSH): Like HS grade, but with a minimum surface hardness of 42 HRC and a core hardness of at least 224 HB.

A polished sucker rod runs inside the stuffing box and provides a connection between the surface pumping unit and the downhole sucker rod string.

Furnished with a wear resistant and anti-corrosive coating, Sovonex™ polished rods reach 65 on the Rockwell “C” hardness scale (65 HRC). This special surface finish enhances the pressure seal of the stuffing box and extends the service life of the rod.

Our polished rods are manufactured to API 11B and are available in the following diameters:

• 7/8”, 1”, 1 1/8”, 1 1/4”, and 1 1/2” (22.23 mm, 25.40 mm, 28.58 mm, 31.75 mm, and 38.10 mm).

Hollow sucker rods form an open passage from the well surface to the bottom of the well that provides several advantages in a variety of production scenarios:

Heavy crude production: Our special skin effect heating system heats up the tubing fluid over the full length of the hollow sucker rods, thus significantly enhancing production of heavy crude. Besides reducing fluid viscosity, paraffin buildup is also minimized.

Chemical injection: Build around an upper hollow rod string connected to an injection unit and a lower solid rod string, our chemical and water injection system reduces fluid viscosity, controls corrosion and scale buildup. Pumping does not need to be interrupted during well washing procedures.

PSP production: Hollow sucker rods resist higher torsion loads (need to verify) than solid rods which makes them ideal for use with progressive cavity pumping systems.

The hollow rod connector and coupling are welded to the two ends of seamless steel pipe through friction welding.

Sovonex™ hollow sucker rods are available in the following diameters:

• 1.25”, 1.34”, 1.42”, 1.50”, and 1.65” (32 mm , 34 mm, 36 mm, 38 mm, and 42 mm).