What is HFW Pipe
HFW pipe (High-Frequency Welded pipe) refers to steel pipe manufactured using a process that employs high-frequency current to heat the edges of a steel strip, followed by welding through mechanical pressure (squeezing).
In the steel pipe industry, HFW pipe and ERW pipe (Electric Resistance Welded pipe) are frequently mentioned together. In reality:
ERW = Electric Resistance Welded pipe (a general term)
HFW = High-Frequency Electric Resistance Welded pipe (a specific, more advanced form of the ERW process)
The vast majority of ERW pipes produced today in accordance with standards such as API 5L, ASTM A53, and ASTM A500 utilize the HFW process.
The Development History of the ERW Process
The ERW process has a long history of development, encompassing LFW (now largely obsolete), MFW (rarely used), HFW (the current mainstream process, with a frequency range of 10 kHz to 500 kHz), and HF-ERW (the mainstream process for API line pipe, operating at 100–500 kHz).
HFW is categorized into two types: Contact HFW and Induction HFW; of these, Induction HFW is the more widely applied method.
