Definition - What does Buttress Thread mean?
Buttress Thread is the thread profile that is made on pipelines and wellbore tools. This thread profile is also used in liner tubular and well casings as well. The profile of these threading is usually in square cut shape. When the thread comes in contact with the mating thread, a hydraulic seal is created through interference fit which allows the buttress-threaded equipment to lock firmly.
Petropedia explains Buttress Thread
In oil field tubing, a Buttress Thread profile is usually designed for superior hydraulic seals. Any equipment that is designed with Buttress Threads has a transmission of force which is parallel to the axis of rotation of the equipment. There are various types of Buttress Thread profiles that are used for various equipment, pipelines, well casings and tubular, they include:
- Simple Buttress Thread profile
- Buttress Thread form as per ANSI 45 degree by 7 degree ( 45°/7° )
- Buttress Thread form as per British standards ( 45°/7° )
- The 45°/7° Buttress Thread form
- Buttress Thread form as per German standards (33°/3°), also known as “Sägegewinde”.