What Are Sucker Rods Used For?

Oil Pump with Sucker Rod

The extraction of oil from the earth has taken many forms throughout history. As far back as ancient Babylon, naturally occurring asphalt was just collected off the ground for use in construction.

By 342 AD, oil was being pulled out from pits in China that were dug using metal bits attached to the end of bamboo poles. Six hundred years later, bamboo served as a pipeline to convey the oil out of wells.

But we’ve come a long way from picking asphalt off the ground or bamboo pipes. 

Modern mechanical lift oil wells typically consist of three broad areas:

  • The famous pumpjack sits above ground.
  • The downhole pump situated at the bottom of the well
  • The sucker rod string, a series of metal or fiberglass rods threaded together that connects the pumpjack to the downhole pump.

Pumpjacks are a common sight the world over, and pumps are an everyday word, but sucker rods are a mystery to many.

What is a Sucker Rod?

When a well is first drilled, the oil may be under enough pressure to push upward naturally, but this is just temporary. Nearly all oil reservoirs will eventually need to bring the oil to the surface using a pump.

This is easier said than done as the oil reservoir is deep underground–typically 30,000 ft or 9000 meters down. How can mechanical energy produced at the pumpjack be transferred thirty thousand feet to the pump? 

The answer is sucker rods

  • Strong Metal or fiberglass rods
  • Threaded on both ends so that they can be fastened together to the desired depth
  • Length varies between 25-30 ft (7-9 meters)

While all components are important for the smooth operation of an oil well, the sucker rods are put under uniquely intense strain. The top sucker rod must convey the weight of all connected rods underneath it as well as all of the oil being moved. Proper design, installation, and maintenance are critical.

Sucker Rod Types

  • Steel Sucker Rods – These workhorses make up the bulk of sucker rods used in the industry. They’re easy to install, durable, and handle compression forces well.
  • Fiberglass Sucker Rods – This alternative material is more durable and light compared to steel, which puts less strain on the entire assembly but is more expensive and has trickier installation.
  • Polished Rods – This rod is the topmost in the string and attached to a tight seal that prevents oil from flowing too far up the string.
  • Pony Rods – These are short sucker rods of varying lengths used to get the precise depth necessary for the entire string of sucker rods. They’re typically utilized below the polished rod to easily set the exact length of the entire string and above the polished rod as a safety net to catch the string if the polished rod comes unattached.

Reddy Pipe is Here to Help!

Reddy Pipe & Supply Inc has more than three decades of experience to ensure your rig is getting the right sucker rod for your well. Our sales and service team is on hand 24/7 to provide the help you need for optimal uptime.

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