SS 309 Shield
SS 309 Shield - erosion shield for boiler protection
Multi-grade heat resistant alloy tube erosion shield, semi-circular / wave fin / outer bend structure, matched snap ring fasteners for full boiler heating surface abrasion protection.
Tube shield erosion protection shield, also called boiler anti-abrasion tube cover, is a customized stamped heat-resistant alloy component designed to wrap the outer wall of boiler heat exchange tubes. In coal-fired power plants, CFB boilers and biomass waste incineration boilers, high-speed fly ash and sulfur-containing flue particles continuously impact the heating surface tubes, which easily leads to wall thinning, perforation and unplanned boiler shutdown.
This series erosion shield forms a buffer barrier between flue medium and base tube, greatly reducing direct particle scouring. We produce three mainstream structural types: semi-circular single tube shield for straight economizer tubes, wave fin baffle for fin transition abrasion zones, and outer bend wrap shield for elbow tube bundle impact positions. Multiple alloy grades are available to match different flue temperature and sulfur content working conditions.
Matched C-type and U-shaped snap ring fasteners are supplied together for quick field installation without full welding, widely adopted in power plant boiler overhaul and anti-abrasion renovation projects worldwide.
We supply three main categories of tube erosion protection solutions to fit all boiler flue harsh working environments, including mechanical metal tube shields, ceramic composite lining shields and anti-abrasion protective coatings:
Stamped heat-resistant alloy components forming a physical barrier around heat transfer tubes to block fly ash impact. Manufactured into semi-circular plates, locking bands and full wrap sleeves, they ensure easy snap-ring installation, stable mechanical strength, and are the most widely adopted anti-abrasion solution for power plant economizers and superheaters.
Integrating high-hardness alumina ceramic tiles with a steel outer shell, these shields deliver superior erosion resistance, acid-base corrosion resistance, and high-temperature oxidation performance. Ideal for severe abrasion, high-sulfur and ultra-high temperature furnace zones, they extend service life multiple times and reduce long-term maintenance costs.
Spray-applied abrasion-resistant layers directly onto the raw tube outer surface without additional wrapped components. Materials include high-temperature polymer, fused alumina ceramic slurry, and special anti-sulfur alloy coatings—suitable for narrow, compact tube bundles where mounted shield sleeves cannot be installed, forming a thin, uniform anti-scour protective film.
Our full range tube erosion shields balance high temperature resistance, sulfur corrosion resistance and project cost, solving core abrasion pain points of boiler tail heating surfaces:
Each alloy grade has fixed applicable temperature and flue medium scope, customers can select matching material according to boiler actual flue working condition:
| Alloy Grade | Material Category | Max Continuous Service Temp | Core Applicable Boiler Zone |
|---|---|---|---|
| 1Cr6Si2Mo | Cr-Si-Mo Heat Resistant Alloy (Non Stainless) | ≤600℃ | Economizer & low temperature superheater, sulfur flue low cost option |
| 1Cr13 | Martensitic Stainless Steel | ≤550℃ | Light abrasion low-temperature tail flue without high sulfur content |
| 309S (Cr23Ni13) | Austenitic Heat Resistant Stainless Steel | ≤850℃ | Medium-high temperature superheater, mainstream universal high temp shield |
| 310S (Cr25Ni20) | Ultra High Temp Austenitic Stainless Steel | ≤1150℃ | Furnace arch, dense phase severe scouring high temperature zone |
Material Selection Tip: For power plant economizer renovation projects with flue temperature below 600℃ and sulfur ash, select 1Cr6Si2Mo to cut overall spare parts cost; high temperature furnace outlet positions adopt 309S or 310S stainless shield.
All tube shields adopt integrated hydraulic stamping forming, strictly control raw material composition and dimensional tolerance before factory delivery:
Stock semi-circular tube shields match global mainstream ASME SA179, SA210, SA213 heat transfer tube outer diameters, non-standard arc and length fully customizable:
| Matched Base Tube Outer OD (mm) | Alloy Plate Thickness (mm) | Shield Total Length Range (mm) | Common Structural Form |
|---|---|---|---|
| 32 / 38 / 42 | 6 / 8 | 100 ~ 1200 | Semi-circular single tube erosion shield |
| 51 / 57 / 60 | 8 / 10 | 150 ~ 1800 | Semi-circular wrap / flat fin protective plate |
| 76 / 89 | 10 / 12 | 200 ~ 2500 | Wave shaped fin baffle / outer bend full wrap shield |
Note: Extra thick alloy plate, super long length and special large radian outer bend shield can be developed with new stamping molds per customer boiler technical drawings.
We supply two mature installation solutions to adapt different boiler overhaul construction cycles and abrasion intensity:
All matched snap rings are produced with same alloy grade as tube shield, eliminate galvanic corrosion caused by dissimilar metal contact in high temperature flue environment.
| Supporting Product Name | Core Function | Matching Application Scene |
|---|---|---|
| Tube Shield Erosion Protection Cover | Outer wall buffer anti-scour wrap for single heat transfer tube | Economizer, low & medium temperature superheater straight tubes |
| C / U Shaped Alloy Snap Rings | Quick locking fastener for semi-circular tube shield | Small & medium diameter tube bundle non-welding installation |
| Wave Fin Anti-wear Baffle | Inter-fin ash impact buffer plate between adjacent tubes | Water wall fin transition severe abrasion zone |
| Cast Alloy Pipe Clamp | Heavy duty saddle fixing support for tube bundle assembly | Large size tube shield overall fixed layout |
Tube erosion protection shields target all heating surface positions suffering fly ash particle and sulfur flue scouring in industrial boilers:
Application zone reminder: 310S grade high temperature shield is mandatory for furnace arch dense phase zone above 850℃; 1Cr6Si2Mo material is the most cost-effective choice for economizer below 600℃.
| Contrast Item | 1Cr6Si2Mo Shield | 309S Stainless Shield | 310S Stainless Shield |
|---|---|---|---|
| Max Continuous Service Temp | 600℃ | 850℃ | 1150℃ |
| Sulfur Flue Corrosion Resistance | Excellent, dedicated Si-Cr formula | Medium, prone to sulfide corrosion under high sulfur flue | Good high temp oxidation, general sulfur resistance |
| Raw Material Procurement Cost | Low, nickel-free alloy | Medium, medium nickel content | High, high nickel-chromium composition |
| Main Boiler Application Position | Economizer, low temp superheater tail flue | Medium high temperature superheater tube bundle | Furnace arch, ultra-high temperature severe scouring zone |
| Long Term Project Comprehensive Cost | Low initial investment, stable service life | Medium one-time purchase cost | Highest upfront procurement cost |
Different alloy grades have matched construction standards, follow operating rules to extend tube shield service cycle and avoid base tube damage:
1. Hoisting reminder: Do not violently hammer shield plate surface during transportation and installation, prevent invisible stamping cracks inside alloy plate.
2. Welding operation requirement: 1Cr6Si2Mo material needs 300~400℃ workpiece preheating before welding, slow cooling after welding to eliminate cold cracks; 309S / 310S stainless shield adopt low-current argon arc welding without high preheating.
3. Snap ring locking installation: Ensure shield fully fits tube outer wall without gap, lock snap rings symmetrically at both ends to prevent shield sliding under long-term flue gas impact.
4. Annual boiler overhaul inspection: Check shield plate thickness thinning degree and welding crack condition, replace severely worn shields in advance to avoid base tube abrasion leakage accident.
5. Storage protection: Stack finished shields with isolation paper between layers, seal warehouse to avoid moisture surface rust before shipment.
The structural and alloy formula of our tube erosion shield is optimized targeting boiler flue ash abrasion working conditions:
1. Arc integral stamping design eliminates assembly splicing gaps, avoid ash accumulation and concentrated abrasion at joint positions compared with tile-spliced protective covers.
2. Graded alloy formula matching different temperature and sulfur content, avoid over-spec high-cost stainless steel for medium temperature tail flue projects to control total overhaul budget.
3. Interchangeable structural forms (semi-circle, flat, wave, outer bend) cover all heating surface layouts, no secondary on-site cutting transformation required for most boiler tube bundles.
4. Uniform plate thickness design ensures synchronous wear speed of whole shield, partial premature thinning will not appear under uneven flue particle impact.
We provide full customized tube erosion shield production according to customer boiler overhaul drawings, flue temperature and ash abrasion parameters:
Customizable parameters: Matched heat transfer tube outer diameter, alloy plate thickness, shield total length, semi-circular arc radian, wave fin height, outer bend wrap coverage angle.
Special customized options: Ultra thick wear-resistant enhanced plate, oversized outer bend shield, pre-welded integrated shield + snap ring assembly for fast installation.
Attached technical supporting service: Boiler anti-abrasion scheme consultation, on-site installation technical guidance, long-term bulk spare parts supply framework contract for thermal power plant annual maintenance.
Tube shields adopt layered isolation shockproof packaging to protect stamped arc structure from extrusion deformation during cross-border sea and land long-distance transportation:
Small batch small-size shields separated by foam isolation paper and packed into fumigated export wooden cases; large quantity bulk finished products stacked on standard steel pallets, fixed with steel binding strips, overall wrapped anti-rust stretch plastic film outside the pallet.
Multiple international trade terms FOB / CFR / CIF are supported, sea freight and land highway transportation available as per customer delivery port and schedule demand.
Each shipment attached complete delivery documents: Alloy material spectral test report, dimensional inspection record, installation operation manual, convenient for overseas power plant project customs clearance and equipment acceptance inspection.
Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique.
Cast basalt lined steel pipe is composed by lined with cast basalt pipe, outside steel pipe and cement mortar filling between the two layers.
Ceramic tile lined pipes have very uniform coating of specially formulated ceramic material that is affixed to the inner of the pipe.
The material of the rare earth alloy wear-resistant pipe is ZG40CrMnMoNiSiRe, which is also the grade of rare earth alloy steel.
Tubes Erosion Shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.
The ASTM A213 T91 seamless tubes are primarily used for boiler, superheater, and heat-exchanger.
When you partner with Sunny Steel, you can stop worrying about meeting deadlines thanks to our responsive and timely service. You'll also say goodbye to unnecessary shopping around. Instead, you'll get white glove service from an expert who understands your needs and can get you the materials you need quickly.
