With the passage of oilfield development time, oil, gas, and water wells are gradually aging, and underground accidents are showing an increasing trend.

As a result, a large number of production and injection wells have been shut down.

This affects and restricts the stable production and normal implementation of development plans in the oilfield.

Effectively repairing those complex accident wells to restore normal production is of great significance for the development of oil fields.

Workover operation refers to a type of operation in oil drilling and subsequent well maintenance, which is usually carried out by a workover rig to ensure the smooth use of the oil well. It can be divided into major repair operation and minor repair operation.

Minor repairs refer to the daily measures taken to maintain the normal production of oil wells, with a variety of types, including pump inspection, sand flushing, salvage, sealing replacement, card removal, rod replacement, wellhead replacement, and other operations.

Major repairs is to eliminate complex underground accidents and restore normal production of oil, gas, and water wells.

Its process flow is relatively complex compared to general underground operations, and it is difficult to achieve construction goals with ordinary operating equipment and technical means.

The content of major operations mainly includes complex fishing inside the casing and casing repair.

In a broad sense, drilling on the inner side of the casing, sealing the oil well string, plugging the oil well, and sealing the abandoned well are also included in the scope of major operations.

The workover rig of Sanjack can do major workover and minor workover both.It is a comprehensive unit mainly used for small and medium repairs and major repairs of oil wells.

The basic requirements for the workover rig in the workover process are:

(1) Lifting ability: In order to lift the drilling tool, it is necessary to have a certain lifting capacity and lifting speed. This function is undertaken by the lifting system of the workover rig.

(2) Rotating ability: In order to drive drilling tools, shaping tools, milling heads, drill bits, and other grinding tools, a certain amount of torque and speed are required for rotating and grinding. This function is undertaken by the rotating system of the workover rig.

(3) Circulating well cleaning ability: In order to ensure normal drilling, flushing the bottom of the well, and carrying drilling cuttings, a certain pressure and flow rate of circulating workover fluid are required. This function is undertaken by the circulation system of the workover rig.

The workover rig with the above three working abilities is called the three working units of the workover rig, which mainly consists of a winch, a well frame, an crown block, a traveling block hook, a rotatory table, a faucet, and a workover pump.