How does API 5L X52 seamless pipe compare in performance to welded pipe?

Since seamless pipes have no welds, the overall structure is uniform and the stress distribution is continuous. When subjected to internal and external pressures, they can better resist pressure and have more stable and reliable strength performance. For example, in high-pressure oil and gas transportation, seamless pipes can better withstand the high pressure during transportation.
Its compressive strength and tensile strength are relatively excellent. Under the same material and pipe diameter conditions, it can withstand higher pressure without deformation or rupture.
Welded pipes are made by curling and welding steel plates or steel strips through welding processes, and the welds are relatively weak links. When subjected to greater pressure, especially when the pressure changes frequently or the pressure peak is high, the welds may crack, affecting the overall strength.
However, with the advancement of welding technology, such as the use of advanced welding equipment and processes, the strength of welded pipes is also constantly improving. Some high-quality welded pipes can meet higher pressure requirements, but overall they are still slightly inferior to seamless pipes.
In terms of corrosion resistance, the inner and outer surfaces of seamless pipes are smooth, without welds, and there are no hidden corrosion risks caused by welds, such as crevice corrosion and corrosion in the heat-affected zone of welding. When transporting corrosive media, it can provide more uniform corrosion resistance.
For some application scenarios that require long-term corrosion resistance, such as underground oil pipelines and chemical medium pipelines, the corrosion resistance of seamless pipes is more obvious and the service life is relatively long.
However, the chemical composition and organizational structure of the weld of the welded pipe may be different from that of the parent material, which is easy to form a corrosion cell, resulting in the weld and its surrounding areas being corroded first. Especially in some harsh corrosive environments, such as humid environments containing corrosive media such as acids, alkalis and salts, the weld corrosion problem of welded pipes may be more prominent.
However, by taking effective anti-corrosion measures, such as coating anti-corrosion coatings and cathodic protection, the corrosion resistance of welded pipes can be improved to a certain extent, narrowing the gap with seamless pipes.