Coal Steam Boiler Tubes Erosion Shield Used For Economizer

Coal Steam Boiler Tubes Erosion Shield Used For Economizer

Coal steam boiler tube erosion shields are essential for economizers in power station boilers, offering 3-5 years of service life. They protect heating tubes from wear, extending boiler efficiency and durability.

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What is an Erosion Shield for Coal Steam Boiler Tubes?

An erosion shield is a protective covering applied to the surfaces of boiler tubes, especially in areas exposed to high-velocity flue gases and abrasive particles. In coal steam boilers, economizer tubes are particularly susceptible to erosion due to the combination of high temperatures and particle-laden gases. By installing an erosion shield, the wear on these tubes is significantly reduced, enhancing the overall efficiency and reliability of the boiler.

Purpose

Erosion shields are used to protect boiler tubes from erosion caused by flue gases coming into contact with the bends of the tubes.


Installation

Erosion shields can be installed selectively in areas that are prone to tube leakage.


Benefits

Erosion shields can protect the boiler's heating surface, such as the economizer, and extend the service life of the boiler.


Materials

Austenitic stainless steel tube shields are often used to reduce fuel ash corrosion in corrosive boiler locations. Materials with higher chromium concentrations, generally greater than 20%, have lower fuel ash corrosion rates.

Features

Benefits

Applications

The Coal Steam Boiler Tubes Erosion Shield for Economizer is a critical solution for industries looking to protect their boiler tubes from the damaging effects of erosion. By investing in erosion shields, facilities can increase the durability of their economizer tubes, improve the overall efficiency of their steam boilers, and significantly reduce maintenance costs. This practical and cost-effective solution ensures that boilers run smoothly and efficiently for extended periods, with less downtime and fewer failures.

Coal steam boiler tubes erosion shield used for economizer is a common component of the heating part of tubes.It is usually used in power station boilers.The useful life of tube shield is 3-5years.The tube shield has a variety of material and the selection of the material shall be subject to the original design of the boiler.The tube shield is divided into straight pipe and bend pipe.The main effect of tube shield is to protect the pipe and increase the service life of the pipe. Boiler tube shields are designed to eliminate major maintenance and downtime costs from boiler and condenser tube failure.

Boiler Tubes

Boiler tubes are metal tubes that heat water to produce steam. They are commonly made of carbon steel or alloy steel and are used in a variety of applications, including power generation, fossil fuel plants, and industrial processing plants.

Boiler Tube Ends

Plain Ends

Ends are perpendicular to the longitudinal axis and free from burrs.

Boiler tube plain ends
Parameter Value
Tube OD 26.7 – 114.3 mm
Tube WT 3.2 – 12.5 mm
Tube Length 4 – 13 m
Deburring Angle α 30° +5° / 37° ±2.5°
Dimension c 1.6 ± 0.8 mm

Welding-Ready Ends

Deburred or specially prepared ends for welding applications.

Boiler tube end preparation for welding Machined boiler tube end

Quality Assurance

All boiler tubes are supplied with comprehensive inspection and testing:

  • ✔ Dimensional and visual examination
  • ✔ Chemical composition analysis
  • ✔ Mechanical property verification
  • ✔ 100% Eddy Current Testing (ECT)

Fire Tube Boiler

Hot combustion gases pass through tubes submerged in a water-filled shell. Heat is transferred through the tube walls by conduction, generating steam for process or power use. Fire tube boilers are typically used for low- to medium-pressure applications.


Water Tube Boiler

Water circulates inside tubes heated externally by combustion gases. Steam separates naturally in the steam drum, with saturated steam drawn from the upper section. Water tube boilers are preferred for high-pressure, high-capacity applications such as utility power plants.

Small diameter cut to length tubes

Main products and applications

Boiler Tubes are metal tubes located inside of boilers that heat water in order to produce steam.

There are two major types of tube boilers: water-tube boilers and fire-tube boilers. In water-tube boilers, water circulates inside the tubes and is heated externally by hot gases generated by the furnace. Boiler tube is installed inside boiler to heat water in order to generate steam, boiler is a closed pressure vessel designed in varieties of types, water tube boiler and fire tube boiler are main types.

  • Welded boiler tubes can be supplied from stock to suit your needs
  • Hot finished boiler tubes can be supplied from new production
  • We can arrange cutting, deburring and testing
  • Boiler tubes can be swaged/bulged to suit your requirements
  • Shipping can be arranged worldwide
  • Stock lengths ranging from 10200-12250mm
Steel Grade Standard Application
GB(China) ASME(USA) DIN/EN(Euro)
Carbon steel 10
20
20G
20MnG
25MnG
SA-106B
SA-192
SA-210A1
SA106C
SA-210C
PH265GH
P195GH
P235GH
St35.8
St45.8
Economizer tube
Water wall tube
Mo steel 15MoG
20MoG
SA-209 T1
SA-209 T1a
SA-209 T1b
15Mo3
16Mo3
Water wall tube
Superheater tube
Reheater tube
Cr-Mo Steel 12CrMoG
12Cr2MoG
12Cr1MoVG
15CrMoG
10Cr9MoVNb
SA-213 T11 SA-213 T22
SA-213 T24 SA-213 T91
A335 P1  A335 P2
A335 P5  A335P9
A335 P11 
12Cr1MoV
14MoV63
10CrMo910
X10CrMoVNb91
10CrMo5-5, 13CrMo4-5
Superheater tube
Reheater tube
Cr-Mo-W steel 12Cr2MoWVTiB SA-213 T23 SA-214 T911
SA-213 T92 SA-213 T122
A335 P23 A335 P911
A335 P92 A335 P122
  ---   Superheater tube
Reheater tube
Austentic Stainless steel   ---   AP304  TP304H
TP321 TP321H
TP347 TP347H
TP316 TP316H
S30432 TP310HCbN
  ---   Superheater tube
Reheater tube

Process flowchart

Boiler tubes process
Small diameter cut to length tubes

Boiler tubes are used in fire-tube boilers, where hot combustion gases pass through tubes surrounded by water in a sealed shell, transferring heat by conduction to generate steam.

Surface Preparation of Petroleum Cracking Tubes

  1. Cleaning: Remove oil, grease, dirt and organic contaminants using solvents or emulsions. This step alone is insufficient for anti-corrosion purposes.
  2. Pickling: Chemical or electrolytic pickling removes surface oxides. Chemical pickling is widely used as a pre-treatment for corrosion protection.
  3. Mechanical Polishing: Use wire brushes or grinding tools to prepare the surface, improving roughness uniformity even if complete oxide removal is not achieved.
  4. Abrasive Blasting: Shot or grit blasting removes residual contamination and creates a consistent anchor profile for coating adhesion.

Proper surface preparation improves appearance, corrosion resistance and coating life. During rainy seasons, hydrogen pickup in steelmaking may increase surface defects such as hairline cracks, which must be removed before service.

Characteristics of High-Pressure Boiler Tubes

  • Operate under high temperature and high pressure
  • Resistant to oxidation and corrosion from flue gas and steam
  • Require high tensile strength and microstructural stability
  • Supplied in fully heat-treated condition
  • Subject to hydrostatic, flattening and flaring tests

Typical applications include superheater tubes, reheater tubes, economizers, main steam piping and petrochemical furnace tubes.

Hardness Testing of High-Pressure Boiler Tubes

Hardness testing evaluates mechanical properties related to formability, machinability and service performance.

  • Tensile Testing: Determines tensile strength, yield strength, elongation and reduction of area.
  • Hardness Testing: Commonly performed using Brinell, Rockwell or Vickers methods. Essential when tensile specimens are unavailable.

Mechanical testing is mandatory for all pressure tube materials referenced in ASME and EN standards.

Steam Boilers

A steam boiler converts thermal energy into steam by heating water. The steam is used for power generation, process heating and space heating.

High-Frequency Resistance Welding (HFW)

Continuous helical fins are attached to the base tube by HFW, producing a forged, solid-state bond without filler metal. Both solid and serrated fins are available.

Widely used in boilers, fired heaters and heat recovery units.

Heat Treatment Defects in Boiler Tubes

Improper heat treatment can leave residual stresses or unstable microstructure, reducing high-temperature performance and affecting the entire heating system.

Why Boilers Use Finned Tubes?

Finned tubes increase the external surface area available for heat transfer between hot gases and the tube wall.

Heat transfer rate depends on:

  • Temperature difference between fluids
  • Heat transfer coefficients
  • Available surface area

Rust Removal Methods

Cleaning
Solvent/emulsion removal of oil and grease (supplementary only).
Tool Descaling
Wire brushing/power tools; reaches Sa2–Sa3, but limited anchor depth.
Acid Pickling
Chemical or electrolytic removal of oxides.
Abrasive Blasting
Preferred method; removes rust and creates uniform anchor profile.

Boiler Pipe Forming

Common forming operations include finning, bending (serpentine coils) and end machining. These processes are essential during fabrication and site installation of boiler systems.

Heat Treatment of Boiler Tubes

Quenching
Rapid cooling after heating to achieve required hardness.
Tempering
Reduces brittleness after quenching; improves toughness.
Annealing
Slow cooling to relieve internal stress and stabilize microstructure.

Proper heat treatment ensures strength, toughness and long-term reliability under cyclic high-temperature service.

Stainless steel related special grade

Material Standard Material
Stainless Steel ASTM 201, 202, 301, 304, 304L, 304N, XM21, 304LN, 305, 309S, 310S, 316, 316Ti, 316L, 316N, 316LN, 317, 317L, 321, 347, 329, 405, 409, 430, 434, 444, 403, 410, 420, 440A, etc.
EN 1.4372, 1.4373, 1.4319, 1.4301, 1.4306, 1.4315, 1.4303, 1.4833, 1.4845, 1.4401, 1.4571, 1.4404, 1.4429, 1.4438, 1.4541, 1.4550, 1.4477, 1.4462, 1.4002, 1.4512, 1.4016, 1.4113, 1.4509, 1.4521, 1.4006, 1.4021, 1.4028, etc.
JIS SUS201, SUS202, SUS301, SUS304, SUS304L, SUS304N1, SUS304N2, SUS304LN, SUS305, SUS309S, SUS310S, SUS316, SUS316L, SUS316TI, SUS316N, SUS316LN, SUS316J1, SUS316J1L, SUS317, SUS317L, SUS321, SUS347, SUS329J1, SUS329J3L, SUS405, SUH409, SUS410L, SUS430, SUS434, SUS444, SUS403, SUS410, SUS420J1, SUS420J2, SUS440A, SUS440B, SUS440C, etc.

Shapes and specifications of tube shields

The cross-sectional shape of boiler tubes shields is mostly semi-circular (180 degrees), and there are also 120-160 degrees.

It is mainly used on finned tubes (water-cooled walls); boiler tube erosion shields are divided into direct wear-resistant shields, in-curve, anti-wear shields, outer-curve, anti-wear shields, side-curve anti-wear shields, s-curve anti-wear shields, etc.

Tube shields-outside bend and side bend types

Tube shields-outside bend and side bend types

The length of the straight anti-wear shields ranges from 20mm to 3000mm, and the general length of 1000-2000mm is commonly used. The anti-wear shields with bends generally requires a processing drawing and the following parameters should be on the drawing: outer diameter of the pipe used, bending of the pipe Radius R (to the center of the pipe), the degree of bending angle, and the length of the straight sections on both sides of the arc segment of the wear-resistant shields.

"snap-on" type shield

Snap on type shield

The most basic parameter of boiler tubes shields is the outer diameter of the tube used (that is, the inner diameter of boiler tubes erosion shields). The main specifications of the tube are: 32, 38, 42, 44.5, 48, 51, 57, 60, 63.5 , 76, 89mm, etc . the inner diameter of the boiler tubes erosion shields is usually 1-3mm larger than the outer diameter of the tube used, depending on the actual requirements.

Tube Shield, Erosion Protection Shield Available Types

  • Tube Shield Manufacturers in China
  • Tube Shield Exporters
  • Tube Erosion Shield Manufacturers
  • Tube Shield Distributors
  • SS Tube Shields Dealer in China
  • Tube Shields Exporter in Shanghai
  • Stainless Steel Tube Shields
  • SS 304 Tube Shields
  • SS 316 Tube Shields
  • Tube Shield for Condenser Tube
  • Tube Shield for Finned Tubes
  • Protection Erosion Shield
  • Snap-On" Type Shield
  • I B" Type Shield
  • Alloy Steel Tube Shields
  • Inconel Tube Shields
  • Incoloy 825 Tube Shield
  • Inconel 600 Tube Shield
  • 1Cr20Ni14Si2 Tube Shield
  • Shield Used For Economizer
  • Replacement Parts Erosion Shields
  • Straight Boiler Tube Erosion
  • Shields For Industrial Steam Boiler
  • 1Cr25Ni20Si2 Tube Shield
  • 304 Stainless Tube Shields
  • Stainless 304 Tube Shield
  • 309 Stainless Tube Shields
  • 310S Erosion Shields
  • Bend Tube Shield
  • Boiler Erosion Shield
  • Boiler House Erosion Shield
  • Shields For Protection Boiler Tube
  • Boiler Tube Protection Sleeve
  • Boiler Tube Shields
  • Inside Of Bend Tube Shield
  • S-Shape Outside Of Bend
  • 304 Stainless Snap Rings
  • U-Shaped Snap Ring
  • Shield Tube Boiler Erosion
  • Boiler Erosion Protection Shield
  • Half Repair Pipe Sleeves
  • 1Cr18Ni9Ti Tube Shield
Bend tube shield

Tube shields production process

The current production process for tube shields is to use high-pressure presses and professional moulds for pressing.

Tube shields from us are manufactured to exacting standards. Advanced equipment and material handling capabilities permit us to offer the fastest turnaround times anywhere.

How to produce tube shield Process

The current production process for tube shields is to use high-pressure presses and professional moulds for pressing.

The production time is short, the welding performance is good, the welding seam does not fall off, the surface is smooth and the appearance is beautiful. The arc-shaped wear-resistant tile is pressed on a press or bent on a pipe bender with a special mould.

PMI test for stainless plate PMI test

PMI Test Plate

To ensure the accuracy of the material. Positive Material Identification (PMI) of stainless steel sheets for tube shields is critical to verifying the grade and composition of stainless steel before it goes into production.

The raw materials for the production of tube shields are generally purchased directly from standard steel mills, and each batch has an MTC. Due to the sharpe limitations of raw materials, it is inevitable that excess materials will be produced. We can use the excess material to make a smaller size snap ring.

Material

Different types of stainless steel are selected according to the specific conditions of different working conditions.

The boiler was originally designed to be accurate. Different materials have different temperature resistance and mechanical strength, generally has a temperature resistance of 600 ℃ or less.

Main material of tube erosion shields

We can also supply boiler tubes erosion shields of other materials.

Tube shield

Advantages of tube shields

Tube shields are custom made to fit perfectly to straight sections, curved sections and even finned and specialised tubing.

Boiler tube erosion shields, also known as anti-corrosion shields, anti-wear plate, anti-wear protection shields, anti-wear cover plate, anti-corrosion cover plate, boiler climbing pipe, anti-wear pressure plate, etc. , which are used in combination with snap rings.

Boiler tube erosion shields are produced using a high-pressure press and professional mould pressing. The production time is short, the welding performance is good, the welding should not fall off, the surface is smooth, and the appearance is beautiful. Boiler tube erosion shields with bends are formed by pressing on a press or bending with a special abrasive on a tube bender.

Boiler tube shields are designed to eliminate major maintenance and downtime costs from boiler and condenser tube failure.

Tube Erosion shield

Service life

The service life of boiler tubes erosion shields is different in different types of boilers and different use parts.

The normal service life is a period of overhaul (3-5 years) for the boiler. Generally, some boilers will be replaced or retrofitted every time the boiler is overhauled. The main replacements are those of the Boiler Tubes Erosion Shields that are severely thinned and exceeded the standard; those that were not firmly detached during the boiler operation during the previous installation. According to the wear of the Boiler Tubes Erosion Shields during replacement, if the thickness is severely reduced, it needs to be replaced, the deformation is severe, and those that cannot protect the tube also need to be replaced. In addition, some boiler tubes are not equipped with Boiler Tubes Erosion Shields, but during the boiler inspection, it is found that the tubes have a tendency of wear and thinning. Generally, Boiler Tubes Erosion Shields are also installed to prevent further wear of the tubes and cause serious consequences such as boiler explosion.

On the heating surface of superheater and economizer tube bundle of the boiler, in order to prevent the pipe from being worn by high temperature flue gas washing, boiler tubes erosion shields are mostly arranged on the outer side of the pipe in the direction of flue gas flow. The elbow erosion shields solves the abrasion problems of water wall tubes, superheater tubes, economizer tubes and reheater tubes in the furnace, and provides guarantee for the long-term and reliable operation of CFB boiler. With the increase of CFB boiler products, the type and quantity of The elbow erosion shields will increase.

Application of Tube erosion shields

Application

Tube erosion shields are mainly used on the windward side of the heating surface of the boiler, such as superheaters, reheaters, economizers, and water-cooled wall pipes.

Erosion shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.

We offer shielding for tubing, covering straight, bent and finned sections, as well as the clips that hold these in place.

In the long term, these shields more than pay for themselves, preventing the costly replacement of tubing and avoiding the downtime that results from tube breakdown and leaks.

In general, most of them are called "wear-resistant tile~and "wear-resistant cover plate~ Erosion Shields are special boiler accessories.

Generally, most of them are used in power station boilers, small boilers are used less, and some coal chemical industries will also use them.

The main role is to protect the heating surface of the boiler pipes, reduce pipeline wear, and increase the heating surface of the pipes.

U-bend tubes with Tube Erosion shield U-bend tubes with Tube Erosion shield
Tube Erosion shield
Tube Erosion shield
Superheater Tube With Erosion Shield Superheater Tube With Erosion Shield
Install erosion shield with snap ring

Installation

Generally, boiler tubes erosion shields are also installed to prevent further wear of the tubes and cause serious consequences such as boiler explosion.

The main role is to protect the heating surface of the boiler pipes, reduce pipeline wear, and increase the heating surface of the pipes.

The snap ring is a short section that is installed on the pipe in conjunction with the wear-resistant tile. Generally, it is welded to the wear-resistant tile by lap welding, that is, to cover the wear-resistant tile slightly, so it is larger than the wear-resistant tile. The opening arc is around 190-200 degrees, the welding position needs to be set aside to facilitate welding and fixing. The width of the snap ring must not be less than 20mm.

The installation requirements of anti-friction tiles of different shapes are slightly different. Basically, each anti-friction tile is installed with not less than 2-4 snap rings. The snap ring and the anti-friction tile are welded together to prevent expansion due to heat. The tiles fall off, and the joints are required to be fully welded.

Packing

Generally, boiler tubes erosion shields are also installed to prevent further wear of the tubes and cause serious consequences such as boiler explosion.

The main role is to protect the heating surface of the boiler pipes, reduce pipeline wear, and increase the heating surface of the pipes.

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