The photo below is of a workover rig in the oilfield. Workover rigs are used to re-enter old wells and pull production pipe or tubing, sucker rods from wells with pumping units, etc. Occasionally workover rigs are used to re-drill existing wells to a deeper depth or horizontally. Workover rigs are truck mounted for easy transportation from well to well. They have many of the same features as a regular drilling rig but only for handling smaller pipe. Sometimes called pulling units, workover rigs are often pulling tubing out of wells for replacement. Roughnecks who work on workover rigs or pulling units like the one in this photo usually have a crew trailer that they tow from job to job.
The workover rig below is owned by Sunset Well Services of Midland Texas.
As on most pulling units or workover rigs as seen in the photo above, the derrick telescopes inward and folds down across the top of the truck for travel. On wells such as the one with a pumpjack above, there will often be permanent tie down rings cemented into the ground for the guy wires to attach to since the well may have to we worked on several times a year to replace pump rods, etc. One of the largest companies doing workover rig work is Key Energy.
The photo below is of a workover rig crew trailer used in the oilfield. The crew trailer may have a stove for cooking meals or fridge to storing food, benches for sitting while eating and lockers for storing hardhats and work clothes. A propane heater may be installed to keep the roughnecks warm when taking breaks or eating meals. The crew of a workover rig often works only during daylight hours, since these rigs are not generally equipped with lights for 24 hour operation.
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