Some Issues About OCTG Casing And Its Transportation

The classification and function of casing

OCTG casing is a steel pipe supporting oil and gas well wall, which ensures the normal operation of the entire well after the drilling process carried out. Different from tubing and drill pipe, casing can not be repeated use and belongs to a one-time consumption of materials. Therefore, the consumption of the casing pipe accounted for more than 70% of all. According to the situation of use, casing can be divided into: tube, surface casing, technical casing and oil layer casing.

Connection type of casing

Short round thread casing connection type

The short round thread casing is one of the product types in the petroleum casing pipe. Short round thread casing features: 1. Improve resistance caused by abrasion when the thread in the screw. 2. When tightening screw, tooth gap provides a reasonable gap for foreign particles and dirt. 3.The arc tooth top is not sensitive for local scratch or dent damage.

Long round thread casing connection type

Long round thread casing is widely used as a buckle-shaped of oil casing. Due to the thread shape at both ends of the pipe body is like long round, so it’s called long round thread casing. Long round thread has the advantages of easy processing, good sealing performance, strong connection strength and cheap, so it’s widely used in the casing connection.

Buttress thread casing connection type

Buttress thread casing have the name because the thread form is like partial trapezoidal and this thread is widely used in all the thread. The packing of the buttress thread casing is tied up with the steel wire or the steel band. The advantages of this thread improve axial tension and axial compression load and the leakage resistance is also provided.

Casing transporting

• Casing before loading and unloading, the inner and outer screw threads must be tightened by special tools.
• The casing should be hoisted with nylon rope.
• The pipe rack car or wagon should pad sleeper which cross section is 150mm×50mm. If the shipment is more than two layer, the sleeper shall be 300mm×60mm.
• When casing loading, external thread or coupling should be installed one end of vehicles.
• Casing vehicle is strictly prohibited overload, over high.
• You should stop in time to prevent casing loosening and ensure safe transportation in transit.
• Casing should be unloaded from the building root in turn. Control casing running speed, avoiding hit front casing when landing.
• The number of loading casing can not more than 10 roots when using forklift and do it gently to avoid collision.