Grate Bars, Cast Iron Fire Grate Bars For Coal Stoker Parts

  • More than 50 types of grate Bars
  • High Si5 & Alloy steel high-temperature resistance
  • Directly manufacturer
  • Most models in stock
grate bars

Different Models And Size Grate Bars

fire grate bar
Passive bars and drive bars is the mainly part of chain grate stoker. Each set of grate stoker boiler will need at least 1000-10000pcs quantities.
grate bars
It is siutable for any capacity range travelling grate bars. Especially popular in Asia country and South Africa, West Africa and etc.
Pinhole grate bars
Pinhole grate bars fullfill small pins. Have good ventilation conditions. Suitable for biomass pellets combustion and solid fuel combustion.
grate bars
You could see the grate bars has four jaws and long holes. Compare to pinhole grate bars. We increase the hole size to suitable for more biomass.
live core fire grate bar
Inner core bar is flexible. You can move or change it freely. Due to its flexibility and non-disclosure features, it is very practical for small-sized biomass.
grate bars
If yours is a solid fuel grate, then most of the designs are this kind of large fire grate. With this design, any of your large solid fuels can burn well.

Our Grate Bars Certifications

  • Certificate
  • Biomass Steam Boiler Certificate 2
  • Biomass Steam Boiler Certificate 3
  • Biomass Steam Boiler Certificate 4

Yongxing Grate Bars Reliable Quality

YongXing is China’s top 3 grate bars manufacturer and supplier. You can choose different sizes and types of grate fireplace accessories from our website.

With the different chain grate stoker boilers, you will find they have different fire grate bars. Once you want to repair them, you need first to get their pictures with size. Usually, we could meet 95% of your demand only with our stock.

What Are The Grate Bars?

Grate bars are used in the chain grate boiler to combust, it is an important steam boiler auxiliary part. These bars have varying alloy structures depending on what kind of fuel is used in the boiler.

Due to the infrequent gaps in the grate bar, the air is circulated for combustion.

The grate bar is a replaceable and wearable component. Its service reliability and expense have a significant impact on the capacity of the boiler and the primary cost of the obtained products. One of the most important conditions for a trouble-free boiler operation is the proper structure and raw material used in the grate bars.

The main requirements for the model of grate bars are sufficient to heat environments, high-quality streamlining, and suitable open grate area distribution.

This also delivers a uniform airflow in individual zones of the grate. Under the high-temperature fuel flow chain effect, Grate bars function well. The material used in the manufacturing of grate bars has to be tough and it should not break.

What Are The Sizes And Shapes You Have?

All these boiler grate bars have different shapes and sizes. Further, the size of the bars depends solely on the client’s needs.
When our stock items meet the client’s needs, they will be delivered immediately. If the product is unavailable in our stock, we make it and deliver it.

We also have different fire grate bar sizes for different boiler capacities. These include 18mm, 24mm for log burner grate bars, large fire grate, grant fire grate, back boiler grate bar, etc. For reference, see some of the following sizes.

Model Grate Bar Material Fire Grate Size
48# Drive grate bar 1.QT450-10.

Heat-resistance 800-900℃

Heat-resistance 1000-1200℃

Hole-to-hole size 80, Width 48mm
48# Drive bar Hole-to-hole size 90, Width 48mm
64# Drive bar Hole-to-hole size 90, Width 64mm
64# Drive bar Hole to hole size 64, Width 64mm
18# Single Driven bars 1.HT150. Heat-resistance 400-500℃
2.RTSi5. Heat-resistance 800-900℃
3.QTSi5.Heat-resistance 1000-1200℃
18# Double Driven bars 18.5mm*80mm
24# Single Driven bars 24.5mm*80mm
24# Double Driven bars 24.5mm*80mm
26# Double Driven bars 26.8mm*80mm

If your quantity is large enough, we also support OEM direct on fire bars. Following are the traditional parts that we have. For more models, please click the following fire bras catalog to choose.

Fire Grate Bar Types And Series

We have different boiler grate bars with various models and materials used to compensate for the temperature needs.

1. Active chain grate bars, also called boiler drive link bar

Every type of grate bar contains various models and different materials used in manufacturing.

Let’s have a look at the models and materials used

2.  Active Chain Grate Bar/Boiler Drive Link Bar

This furnace grate bar is made of outstanding heat-resistant alloy steel, the grate formation, and motion method are very basic and smooth, it does not stick easily, the malfunction rates are very low, and a lot of inspection and renewal costs are end up saved.

The chain grate drive links are supplemented every fourth year, with annual replacement levels of 2% or less. The boiler section’s modular design makes the transportation system and on-site setup easier, and it can be gathered first in the training session to enhance the precision required for on-site setup.

The trash can be quickly sparked and set on fire by the rotational movement of the bar and the decline between the grate. The three parts of the grate successfully dissipate the garbage, resulting in a good unified blending impact of the garbage, ensuring stable burning.

Steam Boiler drive link bars have different models 48# Middle(Pitch 80mm), 48# Side(Pitch 90mm), 64# Middle(Pitch 90mm), 64# Side (L=64mm).

It has QT450-10 and QTSi5 materials used with amazing heat resistance up to 1200°C.

3. Passive Chain Grate Bar

On the lower part of the grate bar, a thermal insert is used to ensure efficient evaporation cooling and prevent overheating.

The grate bar is made of high-quality heat-resistant alloy steel. Boiler bars travelling grate stoker are easy to setup and maintain, and they do not tangle easily.

Make sure that the boiler’s heat exchange area is neat, and that the fluid cooling surface of the heat exchanger of the passive grate boiler, the convection heat tube pack, the evaporator, the air preheater, and other heat source area ash and boiler scalability is not an important problem influencing the boiler’s thermal performance.

Passive chain grate bars have multiple models i.e. 18# Single Wind Groove 18.5mm*80mm, 18# Double Wind Groove 18.5mm*80mm, 24# Single Wind Groove 24.5mm*80mm, 24# Double Wind Groove 24.5mm*80mm, 26# Double Wind Groove 26.8mm*80mm.

The alloy material used in this kind of grate bar is HT150 with Heat-resistance 400- 500°C, RTSi5 with Heat-resistance 800- 900°C, QTSi5 Heat-resistance 1000- 1200°C.

Grate Bar Construction

The structure of different grate drawings is different. Let’s take a look at a few examples of the drawings below.


4. Live Core Chain Grate Bar/Living Core Grate Bar

This is a unique bar with diverse models L=203mm, L=200mm, L=220mm, L=228mm, L=231mm, L=237mm, L=240mm, L=245mm, L=246mm, L=250mm, L=255mm, L=264mm, L=290mm. the materials used in this product are QT450-10 and QTSi5. These are highly strong and heat-resistant materials.

Both of these materials resist temperatures up to 800-900°C and 1000- 1200°C respectively. These fire grate bars are generally used in boilers installation and maintenance.

5. Reciprocating Grate And Step Grate Bar

In essence, it consists of repeating fixed or adjustable grate bars. This type of grate bar is called a lateral or stepped grate.

Through its reciprocating motion, the adjustable grate bar pushes the coal seam to the back burning area, making it more flexible for the boiler.

The models of reciprocating fire grate bars include 320mm, 360mm, 370mm, 450mm. the materials used in this type of boiler are Alloy steel with Heat-resistance >1200°C and QTSi5 with Heat-resistance 1000- 1200°C. Both of these materials are amazing for large applications.

6. Square Chain Grate Bar

Square chain grate bars are available in two different types. The first is with Three jaws. It further contains various models i.e.

L= 117mm, 129mm, 133mm, 167mm, 203mm. whereas the other consists of Four jaws having different models

L= 200mm, 220mm, 230mm, 240mm, 250mm, 265mm, 286mm, 296mm, 305mm, 320mm, 330mm, 350mm, 368mm, 380mm.

it consists of strong material HT150 and RTSi5, which offer amazing heat resistance up to 900°C.

7. Flake Chain Grate Bar

There is a slight tendency between the grate bar area and the horizontal plane. The grate bar generates periodic vibrational movement.

When the boiler vibrates, the fuel layer moves steadily toward the back of the heater. This causes the scorched ash to drop into the ash hole at the end of the grate.

Installing this grate bar is a straightforward process.

It models includesL= 288mm,301mm, 311mm, 314mm, 315mm, 318mm and L=325mm, 330mm, 340mm, 365mm, 368mm. It is composed of HT150 with Heat-resistance 450- 500°C and QTSi5 with Heat-resistance 1000- 1200°C.

8. G Type Grate Bar

G type grate bar is composed of different models Φ800mm, Φ930mm, Φ1100mm, Φ1200mm, Φ1300mm, Φ1370mm, Φ1600mm. it uses the HT150 raw material with Heat- resistance of 450-500°C

What Is Your Grate Bars Manufacturer Process?

The manufacturing methods primarily address the preceding art’s issues of a high-alloy grate bar being intricate in the production chain, relatively expensive in manufacturing cost, complicated in portraying damage control, non-uniform inefficiency.

Our grate bars are made from special and pure materials with a continuous check on the quality.

  • The first step of production is to open mold or use the existing mold.
  • Then the chemical composition analysis is performed
  • The raw material is then melted and pour into the molds
  • For the sake of proper shape and hygiene, experts Make it clean
  • Then go for machining and finally the given dimensions are tested and inspection is performed for tensile strength and hardness.

Can We Customize The Grate Bar? How To Make A Customized Grate Bar?

After looking at the needs of the clients, we proceed and design any type or size of grate bars. Heavy-duty grate bars are available for applications that need power and strength properties. The materials that are used in making grate bars for boilers are stainless steel alloy, Aluminum, and carbon steel.

You just need to tell us your desired raw material and size of bars. Our professional team will work hard for your grate bars to match the needs of your boiler. You’ll get everything fixed in your boiler with proper technical help.

What Is Your Boiler Grate Bar Application?

The purpose of a boiler grate bar is to help and support the solid fuel in the heater. For burning, the grate bars can accept air into the solid fuel. They are designed to do it.

A grate bar base body is set from raw material casting. It is covered with an elevated temp flexible plate on an exterior portion.

As well as this, a hole is implanted in the grate bar bottom body in a corner pointing to the plate. A side hole is implanted in the plate in relation to the grate bar base body all the way through the manufacturing process.

Before the grate bar ground body and protection plate are assembled, this hole is filled at least partially with ceramic fiber shielding material.

There are several options for connecting the plate and the grate bar ground body. In theory, a screw connection, pure compression molding, or something similar is feasible.

However, the cover plate should ideally be linked positively to the grate bar foundation body. Further mechanical interconnect parts, such as screws, can then be eliminated.

A tongue and groove linkage or a bung connection, more ideally a swallowtail connection, connects the grate bar base body in a present invention.

How To Change And Repair Boiler Grate Bar?

Once you have decided to change or repair the boiler grate bar, you need to choose a good source for them.

First, you need to check on the requirements because manufacturers have different grate bars made up of different materials. We have almost all high-quality material grate bars.

Although customization is also available, you can choose your material type and size. However, we have a wide range of available bars that 95% of clients get their needed bars from our stock. For repairing, purposes get the pictures and sizes of your bars and we will help you out to fix them.

How If We Have Special Requests For Raw Materials?

For generations, our corporation has been producing and creating these castings to meet the needs of clients all over the world. We work with OEMs as well as end consumers regularly for the Iron Ore Pelletizing processes, which provides us with the necessary experience to build the perfect products.

Our engineers and experts use a range of materials to start creating grate bars, including cast iron fire bars, malleable steel, gray iron (HT150, HT200), ductile iron (RTSi5, RQTSi5), and cast steel.

While aluminum is a relatively light material, it is well-known for its toughness and reliability. We produce these grate bars with various size spaces between the bars based on the specific needs of our customers so that they can be used for a variety of applications. Our grate bars can also be ordered in a variety of thicknesses.

Heat-Resistant Cast Iron Raw Materials Types

Thermal tubing is available in a variety of very adaptable materials, strongly heat resistant, elevated, increased temperature adaptable, chemical-resistant pipes. It is mostly quite suitable for applications requiring high liquid as well as chemical resistance.

Material Hardness Temperature Working Condition


150 ~200 150°C Heat resistant temperature to 150°C


170~220 200°C Well-suited for applications that need higher chemical resistance.



228~302 700°C – 800°C In the air, furnace gas, heat-resistant temperature to 800°C


160~270 700°C – 800°C In the air, heat-resistant, furnace gas

temperature to 700°C




189~288 500°C-600°C In the air, heat-resistant, furnace gas

temperature to 550°C




400~405 800°C- 900°C In the air, furnace gas, heat-resistant temperature to 900°C. Abrasion is resistant at room temperature and resistant to corrosion.

Pinhole Passive grate bars

Chemical Composition Of Heat-Resistant Cast Iron

CODE Chemical Content Of Different Cast Iron Bars
C Si Mn P s Cr A1
Less than
RTCr 3. 0—3. 8 1. 5〜2. 5 1.0 0.20 0.12 0. 50~ 1. 00 ——
RTCr2 3. 0—3. 8 2. 0〜3一 0 1.0 0.20 0.12 >1. 00- 2. 00 ——
RTCrl6 L6~2-4 1. 5—2. 2 1.0 0.10 0.05 15. 00~ 18. 00 ——
RTS i5 2. 4—3.2 4. 5 — 5. 5 0.8 0.20 0.12 0. 50~ 1. 00 ——
RQTS14 2. 4—3.2 3. 5 〜4. 5 0.7 0.10 0.03 ——
RQTSi4Mo 2.7—3. 5 3. 5 〜4. 5 0.5 0.10 0.03 Mo 0.3~ 0. 7 ——
RQTSi5 2. 4—3.2 >4. 5~ 5. 5 0.7 0.10 0.03 ——
RQTA14Si4 2. 5—3.0 3. 5 〜4. 5 0.5 0.10 0.02 4. 0~5. 0
RQTA15Si5 2. 3—2. 8 >4. 5~ 5.2 0.5 0.10 0.02 >5. 0~ 5. 8
RQTA122 L6~2-2 1. 0〜2. 0 0.7 0.10 0.03 20. 0~ 24. 0

Room Temperature Mechanical Properties Of Heat Resistant Cast Iron

Cast Iron Code Minimum tensile Strength AB Hardness HB
N/mm2 (kgf/mm2)
RTCr 200 (20.40) 189—288
RTCr2 150 (15.30) 207 — 288
RTCr16 340 (34.70) 400—450
RTSi5 140 14.30 160—270
RQTSi4 480 (49.00) 187〜269
RQTSi4Mo 540 (55.10) 197 — 280
RQTSi5 370 (37.80) 228—302
RQTA14S14 250 (25.50) 285 — 341
RQTA15S15 200 (20.40) 302 — 363
RQTA122 300 (30.60) 241-364

High-Temperature Short Time Tensile Strength Of Heat Resistant Cast Iron Bars

CODE Tensile strength at the following temperatures (℃) 6 b/MPa
500 600 700 800 900
RTCr 225 144
RTCr2 243 166
RTCr 16 144 88
RTSi5 41 27
RTQSi4 75 35
CODE Tensile strength at the following temperatures (℃) 6 b/MPa
500 600 700 800 900
RTQSi4Mo 101 46
RTQSi5 67 30
RTQA14S14 82 32
RTQA15S15 167 75
RTQA122 130 77

What Code Of Grate Bars Should I Choose According To My Temperature?

Code Using conditions of different code
RTCr Heat resistant up to 550℃ in air furnace gas
RTCr2 In the air furnace gas, heat-resistant temperature up to 600 ℃
RTCr6 Heat-resistant to 900℃ in air furnace gas, anti-abrasive in greenhouse and high temperature, resistant to nitric acid white and corrosion.
RTSi5 In the air furnace gas, heat-resistant temperature up to 700 ℃
RQTSi4 In the air furnace gas heat-resistant temperature up to 650 ℃, its Si-containing upper limit to 750 ℃, mechanical properties, anti-cracking properties than RATSi5
RQTSi5 Heat-resistant to 800°C in air furnace gas, and up to 900’C with the upper limit of silicon content
RQTAl4Si4 Heat resistant to 900°C in air furnace gas

Chemical Composition Of Commonly Used Heat-Resistant Cast Iron Grate Bars

  • High silicon heat-resistant cast iron: containing 5-6% silicon, its working temperature can be stabilized at 850 degrees, but its mechanical properties are low, can only be manufactured by the lower force of heat-resistant parts.
    The composition of the following table.
Name Code Chemical Composition%
C Si Mn P S Cr
Medium Silicon Heat Resistant Casting Iron RTSi-5. 5 2. 2-3. 0 5. 0-6. 0 <1.0 <0.2 <0. 12 0. 5-0 .9
Heat-resistant cast iron with chromium RTCr-0. 8 2. 8-3. 6 1. 5-2. 5 <1.0 <0.3 <0. 12 0. 5-1 .1
Heat-resistant cast iron with chromium RTCr-1. 5 2. 8-3. 6 1. 7-2. 7 <1.0 <0.3 <0. 12 1.2-1 .9
  • High alumina heat-resistant cast iron: high alumina but good heat resistance (900 degrees), can make a variety of heating furnace bottom plates.
    But the mechanical properties are very poor, and aluminum is easy to oxidation and the formation of slag.
    The composition of the following table.
Name Chemical Composition%
C Si Mn P S AL
Alcoa heat resistant cast iron 2. 5-3. 2 1. 6-2. 3 0. 6-0. 8 5. 5-7. 0
High alumina heat resistant cast iron 1. 2-2. 0 1. 3-2. 0 <0. 7 <0.4 <0. 03 20-24
  •  High chromium heat-resistant cast iron: in general, the amount of chromium added to 0.5-2%.The higher the working temperature, the higher the amount of chromium added should be, when the amount of chromium is 26-30%, the heat-resistant temperature is 1000 degrees.When the amount of chromium is 32-36%, the heat-resistant temperature is 1150 degrees, and the mechanical properties remain high.
Name Chemical Composition%
C Si Mn P S Cr
High chromium heat-resistant cast iron RTCr16 1.6-2. 4 1. 5-2. 2 <1.0 <0. 10 <0. 05 15-18
High-chromium heat-resistant cast iron RTCr28 0. 5-1.0 0. 5-1.3 0. 5-0. 8 <0. 10 <0. 08 26-30

Grate Bars Technical Advantages

All grate bars are cast inside the boiler in a boiler that is fueled by biomass. To improve strength and cooling, we can create custom shapes. At your location, we adapt the metal structure according to the fuel conditions. We also have an engineering team to perform assessment and safety checks.

Thermal Process Growth can help with regulation work for air license testing, better firing, ignition system refurbishments, and upgrades.

How Do You Make Grate Bars Quality Control?

With the effectiveness of organizational structure, we create a series of grating bars investigation for quality assurance all through manufacturing. Furthermore, before dispatch, we will re-inspect the items to ensure that they are eligible and in fine shape when our clients receive them. The following are the inspection items:

  • Visual Examination

To ensure a visually appealing and incorporated exterior, each grate bar is individually checked. If there are any flaws, they will be identified and supplanted with qualified products.

  • Sizing Examination

They will be thoroughly checked with meter rods, Vernier calipers, micrometers, and other highly qualified assessment methods, regardless of layer thickness, carrying bar and crossbar size, or overall width, length, and height. All sizes must adhere to the tolerances of International Standards as well as the demand of the clients.

  • Performance evaluation

The load effectiveness of the steel grating will be sampled and checked following customer requirements and global standards. In addition, the test result will be produced with the steel bar products.

  • Package Examination

The grate bar is commonly stuffed in steel belts or wooden frame pallets. The specific scenario and the demand of the clients should determine the amount and weight of each bundle. To accommodate the pressure impact all through transportation, the entire package should be solid and restrictive.

  • Label Examination

Before dispatch, the bars will be labeled. The label will include the following information: brands, company, specific requirements, volume, and norms. Other information will be tailored to the customer’s needs.

  • Inspection For Quality Standards

Products are delivered with quality certification. The credential will include inspection results, such as shape and effectiveness evaluations. Furthermore, mill certification of raw resources can be delivered concurrently based on the needs of the client.

Here, Yongxing produces them with established procedures and rules. We will make your grate bar as the following process:

  • Open mold/ or use existing mold
  • Chemical composition analysis
  • Melt
  • Pour
  • Make it clean
  • Machining
  • Dimension inspect
  • Tensile strength test
  • Hardness test

In these chemical compositions, our most commonly used materials are cast iron fire bars, like HT150, HT200, HT250, RTSi5, QTSi5, etc.

Take our RTSi5 material, for example. Once you need a fire grate bar that can bear high temperatures up to 1200℃, this kind of material is the best option.

Some customers may need a temperature higher than 1200℃ or need them to work more long lifetime. They are welcome to choose our alloy steel grate bar, with materials of ZG35Cr24Ni4SiN. The side plate also uses ZG35Cr24Ni4SiN. Endplate use QTRSi5.

How We Sure We Buy The Right Quality From You?

If your quantity is enough, then we will make the test report for you. And we ever have test with our alloy grate bars. That is an excellent appearance. Check to follow pictures.

High quality alloy steel grate bar
High-quality alloy steel grate bar

Do You Grate Bar Foundry Yourself?

Yes, we have our own cooperation grate bar foundry.

Possessing our foundry enables us to offer the highest quality command and guarantees the customer that the grate bar from the YongXing boiler factory will last a long period with minimum disruption for maintenance and upkeep.

We can customize your boiler’s existing grate bars based on YongXing’s consolidated biomass combustion insights and thermal process development.

Don’t hesitate to cooperate with us, we will always support you with the best fire grate bars. Send inquiry right now.

fire grate bar for back boiler
fire grate bars size 24#
Welcome To Your Visit Of Grate Bars

Different shapes of grate bars viewed in video

Yongxing Grate Bars Quality Control

Grate Bars, Cast Iron Fire Grate Bars For Coal Stoker Parts
48mm drive bars for shipping
Flake chain grate bars chain grate stoker


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