Pup joints are short tubular sections used to precisely adjust casing and tubing string lengths during oil and gas well construction. They are manufactured in a wide range of outer diameters and corresponding lengths to suit different applications. Understanding common size standards helps engineers select optimal products.
3 1/2" EUE Pup Joints
3 1/2" joints with external flush (EUE) threaded connections are frequently used in intermediate casing strings of shallow to moderate depth wells. At this diameter, they provide adequate strength and drift clearance while allowing efficient drilling and cementing operations.
The3 1/2" size balances annular space for mud circulation with production flow area optimization. 31⁄2” EUE pup joints allow tuning the string length in small increments versus using full-length joints. Short 3 1/2" stubs help fine-tune positions, while longer extenders add length.
At this medium diameter, the flush EUE design prevents hang-ups during installation and minimizes flow restrictions. 3 1/2" EUE joints are manufactured in standard API casing grades like J55, K55, and N80 to suit different strength requirements.
2 7/8"
2 7/8" is a common production tubing size where precise length adjustments are needed to land equipment at planned depths. 2 7/8" EUE joints enable tuning the tubing string length in small intervals versus whole joints.
Like 3 1/2" variants, the 2 7/8" EUE flush threads minimize damage risks running in the hole. The EUE design also reduces turbulence and pressure loss. 2 7/8" joints are typically produced in corrosion-resistant alloys like J55S or L80T for tubing durability.
At under 3” diameter, 2 7/8" products provide flexibility plus ruggedness. They facilitate building custom tubing strings tailored to exact dimensional specifications. The flush EUE connections prevent hang-ups during tricky tubing installations.
13 3/8" Seamless Joints
13 3/8" diameter joints are often used in large hole sections such as for conductors and surface casing. At this size, seamless rolled steel provides maximum strength compared to welded variants.
The thick walls enable 13 3/8" joints to provide weight for casing string load management as needed. Common lengths range from 5-15 feet. The seamless fabrication combined with API threading delivers pressure capacity for a big casing.
13 3/8" represents the point where seamless manufacturing becomes preferable to welded methods. this size and up are available in high-strength grades including J55, N80Q, and Q125 to provide exceptional performance.
20” Seamless Joints
20” joints represent the maximum diameter used in well construction. At this substantial size, seamless rolled steel from continuous cast billets yields reliable, high-strength joints. The thick walls provide weight for heavy string load control.
20” joint are selectively used in applications like conductor setting and drilling large-diameter salt formations. Their heavy weight aids collective string load management as they are less prone to handling damage than smaller sizes.
Proprietary premium connections are typical for 20” pup joint given their criticality and high replacement cost. Maximum lengths are normally 20 feet due to handling challenges. The focus is on utmost strength and integrity over diameter optimization.
Appropriate pup joints dimensions are key to achieving well architecture aims. If you are unsure about what size you need for your project or require a product in a specific size, please contact us at info@vigorpetroleum.com.
