SA213-TP304H , NPS 2'' X SCH80S, continuous helical welded heat
exchanger fin pipe
High Frequency Resistance Welded Helical Steel Fin Tubes is widely
used in the recovery of waste heat from boiler flue gas.
General HF welding production capacity
|General specifications of HF welding fin tubes|
Welding Facility: 4 finning machines;
Daily production capacity up to 40 tons;
HFW Fin type: solid plain and serrated.
Tube OD: 19mm min.
Tube Length: 18 meters max.
Fin Height: 32 mm max.
Fin Thickness: 0.8mm min
Fin Pitch: min. 4 mm for solid fins and 3.3mm for serrated fins.
General Manufacturing Process: The fin strip is welded continuously and spirally wound onto a
polished bare tube. And the tube and fins are bonded together by
using high frequency resistance welding technique.
We produce both solid plain and serrated helical welded steel
finned tube. And also, all spiral welding tubes could be bent in
the middle or at the end of fin tubes, we call it Hairpin tubes.
Basis parameters for helical welded fin tubes:
- High frequency welding machine output power supply: 200KW or 300KW
- The High Frequency Resistance Welded Spiral Fin Tube quality is
assured by hydrostatic or pneumatic tests and tensile tests in
order to verify the mechanical bonding between bare tube and fin
- Acceptance criteria: INTERNATIONAL STANDARD FOR DIMENSIONS,
TOLERANCES, AND TESTS OF HIGH FREQUENCY RESISTANCE WELDED FINS or
the delivery conditions (TDC) of clients.
- Visual check: un-welded parts of fin, fin damage after fining,
copper pollution, tears, wrap etc…
- Dimensional check: fin height, fin spacing, fin inclination, fin
corrugation, length of finned & un-finned portion etc…
- Bending check: ovality, thickness and area reduction.
- Coating: outside-Red oxide zinc phosphate primer and inside
volatile corrosion inhibitor (VCI) in water soluble tablet form.
- Fin end finish: Bevel(30~35degeree)
- Delivery condition: Tube ends are square cut, free burrs,
internally dried and air blown clean, externally coated with
varnish at both ends of helical welded tubes. The desiccants are
put into the each package for continental transportation as well.
- Documentation shall include QAP, WPS, PQR& WPQ, raw materials
mill certificates, inspection and test samples results and warranty
certificate of manufacturer.
The High Frequency Resistance Welded Helical Fin Tubes are widely
applied in fired heaters, heat exchanger, boilers, economizers,
pre-heaters, coolers, heat pipes, heaters etc….
A wide range of fin and tube materials could be combinations are
|Items||General Materials||Popular Materials|
|Core Tube Material|
Carbon Steel , Alloy Steel, Heat Resistant Steel,Stainless Steel
1. Carbon Steel: A179/A192/SA210/P235GH etc..
2. Stainless Steel: TP304/304L,
TP316/TP316L, A789 S31803/S2205 etc...
3. Alloy Steel: T11/T13
Carbon Steel , Alloy Steel, Heat Resistant Steel,Stainless Steel etc.
1.Carbon Steel: Spcc
2. Stainless Steel:
Helical steel fin tubes fabrication Range
Additional supply range :
(1) Tube swaging process for joint of 2 tubes.
(2) Spacer rings (material: steel) are available.
(3) One side is solid plain fins and the other is serrated fins, 2
fin types on same tube.
- We have more than 10,000 square meters workshop, including 4 ERW
high Frequency welding fining lines, daily capacity around 40
Tons;Our quality assurance plan for High Frequency Welding Spiral
- Our quality assurance plan for High Frequency Welding Spiral Steel
Tubes. (2.1) Raw material control for both plain tubes and fins.
(2.2) In process control with reports,as WPS, PQR&WPQ; weld
deposition efficiency test before fabrication, Non-destructive test
and tensile test etc. (2.3) Final inspection control with reports
(Visual and dimensional check etc…).
- The High Frequency Resistance Welded Fin Tube is integrally
extended for the max surface area to achieve efficiency. The heat
transfer ratio of high frequency welding fin tube is about 8~9
times higher than other plain tubes.
- This Welded Helical Fin Tubes is a singular integral unit,
eliminating heat contact resistance and losses. Generally tube side
temperature up to 800 degree for stainess steel fins; Low carbon
steels, withstanding up to 475 degree is the most common choice.