What Is a Submerged Entry Nozzle?
A Submerged Entry Nozzle (SEN) is a refractory nozzle that connects the tundish with the mold during continuous casting.
The upper part of the SEN is connected to the tundish-side flow-control system, while the lower part extends into the mold and remains submerged below the surface of the molten steel and mold flux during casting.
The basic steel flow path is:
Ladle → Tundish → Submerged Entry Nozzle → Mold
The SEN provides a protected passage for molten steel and directs the steel stream into the mold through one or more outlet ports.
Because the nozzle geometry influences the direction and velocity of the steel jets entering the mold, SEN selection is closely related to the customer’s casting process and mold configuration.
What Does a Submerged Entry Nozzle Do?
For a continuous casting operation, the SEN has several important functions.
1. Protects the Molten Steel Stream
The SEN provides a refractory passage between the tundish and mold and keeps the steel stream below the surrounding atmosphere during normal submerged casting.
This helps reduce direct atmospheric exposure of the molten steel during transfer.
2. Directs Molten Steel into the Mold
The SEN controls where molten steel enters the mold through its outlet ports.
The number, size, position and angle of the ports can affect the resulting flow pattern inside the mold.
3. Influences Mold Flow Behavior
SEN geometry is an important factor in continuous casting flow behavior.
The outlet port design influences the direction and velocity of the steel jets entering the mold, which in turn affects the flow pattern and turbulence inside the mold.
For this reason, the SEN should be selected together with the mold size, casting speed and steelmaking process rather than treated as a generic refractory tube.
4. Supports Stable Continuous Casting
A suitable SEN design helps provide a controlled and consistent steel flow from the tundish to the mold.
The actual casting result depends on the complete system, including the tundish, flow-control components, SEN, mold and operating conditions.
Submerged Entry Nozzle for Continuous Casting
SENs are used in continuous casting systems where molten steel needs to be transferred from the tundish into the mold under protected conditions.
Typical applications may include:
The exact SEN design should be selected according to the customer’s casting machine and steelmaking conditions.
Different caster configurations may require different nozzle lengths, bore dimensions, outlet-port arrangements and connection designs.
Why SEN Design Matters
When purchasing a submerged entry nozzle, customers often focus first on the material and dimensions.
However, the internal flow geometry is equally important.
The SEN controls the path taken by molten steel as it leaves the tundish and enters the mold.
Important design factors can include:
Bore diameter
Bore geometry
Outlet-port number
Outlet-port angle
Outlet-port size
Port position
Nozzle length
Immersion depth
Connection dimensions
Slag-line configuration
Research has shown that SEN geometry has a significant influence on the flow field inside the continuous casting mold.
For customers, this means that simply replacing an SEN with a nozzle of similar external dimensions may not always provide the same casting behavior.
How to Choose the Right Submerged Entry Nozzle
The right SEN should be selected according to the complete casting application.
Before requesting a quotation, we recommend preparing the following information.
1. Casting Machine Type
Please tell us what type of continuous caster you are using.
For example:
This helps determine the general nozzle configuration.
2. Mold Dimensions
Mold dimensions are important when determining the appropriate SEN configuration.
Please provide, where applicable:
Mold width
Mold thickness
Mold section size
Mold type
Number of strands
For slab casting, the mold width and thickness can be particularly important when evaluating the nozzle port arrangement.
3. Casting Speed
Please provide the normal casting speed or operating range.
Casting speed affects the molten steel flow rate through the SEN and should be considered together with nozzle bore and outlet-port design.
4. Steel Grade
Please tell us the steel grades you are casting.
Different steel grades and steelmaking conditions can create different requirements for nozzle performance.
Useful information may include:
If you have several steel grades, please list the main grades for which the SEN will be used.
5. Existing SEN Dimensions
If you are replacing an existing SEN, please provide the current dimensions.
Useful measurements include:
A technical drawing is preferred if available.
SEN Port Design
The outlet ports are one of the most important parts of a submerged entry nozzle.
The ports determine how molten steel exits the nozzle and enters the mold.
Depending on the casting application, SENs may use different outlet configurations.
Possible design variables include:
The correct configuration should be determined from the customer’s casting parameters rather than selected only from a standard catalogue.
A change in port geometry can change the direction and characteristics of the steel jets entering the mold.
SEN for Slab Continuous Casting
Slab casting applications often require careful control of the steel flow entering the mold.
For slab casters, SEN design may consider:
Mold width
Mold thickness
Casting speed
Steel grade
Nozzle immersion depth
Outlet-port angle
Port configuration
Mold flow requirements
If you are replacing an existing slab SEN, providing the existing nozzle drawing is the best way to communicate the required configuration.
SEN for Bloom and Billet Casting
Bloom and billet casters can have different mold dimensions and flow requirements from slab casters.
The SEN should therefore be matched to the actual caster and section size.
For smaller-section casting applications, the nozzle geometry and outlet configuration may be different from those used on large slab casters.
For replacement orders, we recommend using the customer’s existing drawing, dimensions or sample as the primary reference.
SEN Replacement
If your current submerged entry nozzle is being replaced, you can send us the information from the existing product.
The most useful information includes:
If possible, please also provide a photograph of the SEN installed on the tundish and mold.
This helps our technical team understand the actual installation environment.
Can You Customize a Submerged Entry Nozzle?
Yes.
SENs are often customized according to the customer’s continuous casting equipment and operating conditions.
Customization can include:
If you have a technical drawing, please send it to us for evaluation.
For a new project, we can review the available casting information and confirm the product configuration before production.
SEN Material Selection
Material selection is an important consideration for submerged entry nozzles because the product is exposed to molten steel, mold flux and severe thermal conditions.
SENs are commonly manufactured using refractory systems designed to balance requirements such as thermal shock resistance, erosion resistance and corrosion resistance. Depending on the design, alumina-carbon and zirconia-containing refractory systems are among the materials used for SEN applications.
However, the appropriate material composition should be determined according to the actual product design and customer’s casting conditions.
For this reason, we do not recommend choosing a SEN based only on a generic material name.
Please provide the steel grade, casting conditions and current SEN specification so that the appropriate product configuration can be evaluated.
SEN Slag-Line Requirements
The slag-line region of a submerged entry nozzle can be exposed to interaction with mold flux during casting.
For demanding applications, customers may require a dedicated slag-line design or material configuration.
The appropriate solution depends on:
If you are experiencing excessive slag-line erosion, please provide information about the current nozzle and operating conditions.
This allows the problem to be evaluated from both the product and process perspectives.
SEN Anti-Clogging Considerations
Nozzle clogging can be an important concern in continuous casting, particularly when inclusions accumulate within the nozzle bore.
SEN research and industrial practice have examined nozzle geometry and specialized internal materials or liners as approaches to managing clogging behavior.
If your current SEN has experienced:
please provide photographs of the used nozzle and your current casting conditions.
This information can help identify whether the issue may be related to the nozzle configuration, material selection or operating conditions.
Quality Assurance
Submerged entry nozzles are functional refractory components used directly in the continuous casting process.
Dimensional accuracy, internal geometry and product consistency are therefore important when selecting a supplier.
Qingdao Zhongye focuses on manufacturing refractory products according to customer requirements and confirmed product specifications.
For customized SEN orders, key dimensions and technical details can be reviewed before production.
Customers can provide:
This provides a clear reference for manufacturing and helps reduce dimensional misunderstandings.
Manufacturing Experience
Qingdao Zhongye High Temperature Material Co., Ltd. was established in 2012 and operates manufacturing facilities covering approximately 36,000 square metres.
Our product range includes industrial crucibles for metal melting, continuous casting refractories and tundish refractory products.
Our continuous casting products include aluminium-magnesium-carbon refractory components such as integral plug bars, immersion nozzles, quick-change nozzles and long nozzles.
This broader manufacturing experience allows us to view the SEN as part of a complete continuous casting refractory system.
For customers, the objective is not simply to purchase a refractory nozzle. The nozzle needs to correspond with the tundish, mold, steel grade, casting speed and operating conditions.
Why Choose Zhongye for Submerged Entry Nozzles?
When purchasing SENs, customers need more than a standard product catalogue.
A suitable supplier should understand:
Qingdao Zhongye provides:
Submerged entry nozzle manufacturing
Customized SEN solutions
Replacement product support
Technical drawing review
Continuous casting refractory experience
International supply experience
Broader tundish and continuous casting refractory manufacturing capability
We focus on understanding the customer’s actual application before confirming the product configuration.
International Supply of SEN Refractories
Qingdao Zhongye supplies refractory products to customers in international markets, including Europe, the United States, Southeast Asia and the Middle East.
For overseas customers, we understand that technical information must be clear before a customized refractory product can be manufactured.
When requesting a quotation, customers can provide:
The more complete the application information, the easier it is to evaluate the appropriate SEN configuration.
Request a Submerged Entry Nozzle Quotation
Looking for a Submerged Entry Nozzle manufacturer or supplier for continuous casting?
Send us your existing SEN drawing, dimensions, sample or photographs.
If possible, also provide your casting machine type, steel grade, mold dimensions and casting speed.
Our team can review your requirements and help determine the appropriate SEN configuration, dimensions and customization requirements for your continuous casting application.
Contact Qingdao Zhongye for a Submerged Entry Nozzle quotation and customized continuous casting refractory solution.
