The advantages of the contiuous inline process are many.
The inline furnace is a continuous furnace line with the pipes butted together. This matters during heating but is even more important is during the quenching.
During the heating process the ends of the pipe are butted together. This allows the entire pipe to receive the same radiant heating. Unlike the open end heating the pipe ends do not heat faster and will exit at close to the same temperature. In some cases when upset pipes are processed some spacing is allowed initially to draw more heat to the thicker portions.
A continuous quench with a short section of quenchant will provide better properties than the semi continuous quench that comes off of a high speed conveyor from a walking beam furnace. It also requires only 25% of the water, reducing pumping costs. Continuous sectional quenching of pipe results in different stress as the growth in this quench is out the length of the pipe as the austenite changes to martensite. Growth of 3 % is not uncommon. For a detailed discussion on the quench process review our quench area.