Modular open-head clamps with AVC arc-length control and integrated wire feeder. Six K-series heads (K76, K114, K168, K219, K273, K325) cover 桅20mm through 桅325mm pipe OD on the FXT40 Pro industrial power source. For pipes 鈮ノ?19mm, the K600 track-type head extends the platform.
Closed-chamber heads are the right choice when the inner bead has to survive a SEMI F20 or ASME BPE inspection. They are not the right choice when the pipe is 6" or bigger, when the wall is 5 mm thick, or when the joint sits in a field trench where there's no clean way to clamp a chamber around it.
The K-series is the open-frame answer. A mechanical ring snaps to the pipe, the torch tracks the exterior, shielding gas flows through the cup. AVC (Arc Voltage Control) reads arc length 50 times per second and adjusts torch height in real time, so wall variation across the rotation doesn't change the weld profile.
K-series heads (K76, K114, K168, K219, K273, K325) cover the full pipe range from 2" instrumentation tubing to 24"+ process and pipeline piping. Paired with the FXT40 Pro industrial-grade power source, the K-series is engineered for open-frame production work where wall thickness, current capacity, and field durability matter more than the compact form factor of the FXT20 that drives C-series and PT-series.
V groove. Small-bore instrumentation tubing, hydraulic lines, skid-mounted piping. 2鈥?0 mm wall.
V or U groove. Process piping on chemical and refinery skids, instrumentation manifolds. 2鈥?2 mm wall.
V or U groove. Mid-diameter process piping, refinery unit headers, shipboard pipe. 2鈥?2 mm wall.
V or U groove. Large process headers, refinery main lines, naval auxiliary piping. 2鈥?2 mm wall.
V or U groove. Heavy process piping, transmission lines, large refinery service. 2鈥?2 mm wall.
V or U groove. Largest K-series, heavy industrial mains and refinery transfer piping. 2鈥?2 mm wall.
Track-type. Long-distance pipeline, large boilers, nuclear main steam. 1鈥?00 mm wall (with cold wire option).
All six K-series modular heads (K76 鈥?K325) plus K600 track-type share one FXT40 Pro power source. Integrated wire feeder (0.8 / 1.0 / 1.2 mm wire), water-cooled host and head, 50-group recipe library. Industrial-grade for production process pipe and field welds.
FXT40 Pro is the industrial-class digital power source FYID-Feiyide engineered specifically for K-series open-frame heads. Higher peak current, AVC arc-length feedback at production duty cycles, and a field-durable enclosure built for trench, refinery, and outdoor pipeline work.
For high-purity tube-to-tube work (C-series closed-chamber) and tube-to-tubesheet work (PT-series), the FXT20 is the compact power source. For open-frame production scale, FXT40 Pro is. Two power sources, two clearly different jobs.
Industrial-grade digital pulse TIG power source. Purpose-built for K-series open-frame heads and production-scale field welding.
K76 / K114 / K168 / K219 / K273 / K325 for Sch.40 carbon, stainless, and duplex pipeline tie-ins. AVC compensates for field pipe out-of-roundness across positions.
Read the methodology 鈫?/a>For heat exchanger shell-side pipe-to-flange and pipe-to-pipe welds, K-series open-frame complements the PT-series tube-to-tubesheet head. Two separate power sources 鈥?FXT40 Pro for K, FXT20 for PT 鈥?covering both sides of the exchanger build.
Read the methodology 鈫?/a>For batch production runs on 4"鈥?6" piping where throughput matters and closed-chamber inner-bead requirements don't, K-series with FXT40 Pro gives orbital repeatability at production scale.
All industries 鈫?/a>The FYID-Feiyide K-series is a family of six modular open-head orbital TIG weld heads (K76, K114, K168, K219, K273, K325) covering pipe OD from 桅20 mm to 桅325 mm. All six are paired with the FXT40 Pro industrial-grade digital power source (three-phase 380V, 21.5 kVA, 5鈥?00A, Siemens S7-200 SMART V3.0 PLC). For pipes 鈮ノ?19mm requiring track-type assembly, the K600 head extends the platform on the same FXT40 Pro power source.
FYID-Feiyide K-series heads are deployed in oil and gas field installations (ASME Sec IX, API 1104), large-diameter process piping, pipeline tie-ins, and refinery retrofits. Customers also use K-series for the shell-side welds of shell-and-tube heat exchangers, complementing the PT-series tube-to-tubesheet head.
Choose K-series for pipe OD over 6", for field welds where chamber assembly isn't practical, and for production runs where the inner-bead doesn't have to meet SEMI F20 or ASME BPE color level criteria. Choose C-series when high-purity inner-bead quality is the deciding factor 鈥?semiconductor UHP, biopharma WFI, sanitary food.
K-series heads include AVC (Arc Voltage Control) that tracks arc length 50 times per second and adjusts torch height in real time. When the pipe wall is thinner on one side of the rotation, the arc length stays the same. Parameters are programmable per quadrant for cases where wall variation is severe.
Yes. K-series open-frame heads are designed for single-operator field deployment; the mechanical ring clamps to the pipe without chamber assembly. Delivery for K-series + FXT40 Pro is confirmed by configuration, production schedule, inspection requirements, and logistics.
Engineering review within 24 hours. Include OD, wall, material grade, position (1G鈥?G), and standard.
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