Overview
Fabrication of Alloy 622 cladded tubes for a superheater in a biomass boiler
Industry
Power & Energy
Location
Osaka, JP
Component/Workpiece
Superheater tubes
Business Type
Integra - Workshop
Job Type
New
OEM
TAKUMA Co., Ltd.
Type of Wear
Tags
Base Metal
Low-alloy steel（STBA12）
General Dimensions (mm)
Ø43 mm × t4.5 mm × L2,000 mm × 20 pcs
The challenge the customer was facing
Tube degradation occurs due to corrosion and erosion caused by steam blowing from soot blowers and the flow of bed material. Although the tubes are coated with Ni-Cr-based thermal spray, cracking and delamination of the coating occur.
Previous Service Life
4mo
How WA solved the challenge
Replacement with Alloy 622 cladded tubes. Single-layer cladding Cladding thickness: approx. 3 mm
Product Category
Wear Pipes & Tubes
Product Description
Alloy 622 cladding
Job Duration
1mo
Technical Advantages
By using Alloy 622, which contains a higher Mo content than Alloy 625, improved resistance to high-temperature environments can be achieved. In addition, cladding with a Ni-based alloy enhances corrosion resistance. Furthermore, cladding provides stronger bond strength and better ductility compared to thermal spray coatings.
Service Life
4y
Photos and visuals for this case study
Annual Cost Before
¥6,000,000.00
Annual Cost After
¥758,250.00
Annual Savings
¥5,241,750.00
87.0% reduction
Annual Cost = (A × E) + (E − 1) × (F + G + H)
Where: A = Cost of Part, E = Parts/Year, F = Maintenance, G = Disassembly, H = Downtime
1 layer(s) documented
Contributor
Yuuki Shimizu
yuuki.shimizu@waj.co.jp
Created
April 30, 2026
Submitted
April 30, 2026
Approved By
Bastien Gerard
May 3, 2026