Tundish Weir Wall & Dam Block Supplier | Corundum Flow Control

Tundish Weir Wall & Dam Block — Corundum Flow-Control Refractory for Inclusion Flotation

A tundish does more than hold steel between the ladle and the mould — it's the last place in the continuous casting process where a non-metallic inclusion has any real opportunity to float out before it ends up cast into the strand. Whether that flotation occurs depends on fluid flow geometry rather than theoretical residence time. A tundish without flow-control barriers allows molten steel to short-circuit directly from the pour box to the nearest outlet. Working in tandem with an engineered tundish cover castable system to prevent thermal loss and secondary air reoxidation, the precast corundum weir wall and dam block physically forces the flow path upward. Engineered with angled through-holes matched to your tundish geometry, our blocks optimize steel cleanliness for demanding automotive, bearing, and SBQ grades before liquid steel discharges through anti-clogging zirconia-core metering nozzles.

Why Flow Pattern — Not Average Residence Time — Decides Inclusion Count

Short-Circuit Flow From Pour Box to Outlet

Without a physical barrier, the shortest path from the incoming ladle stream to the nearest nozzle gets a disproportionate share of total throughput, especially on multi-strand tundishes where one outlet sits closer to the pour box than the others. Steel taking that path gets a fraction of the nominal residence time, and it's exactly that fraction of steel that shows up as inclusion-related defects at the mill's quality inspection, not the bulk average.

Turbulence at the Impact Zone Re-Entraining Slag

The point where the ladle stream strikes the tundish steel surface is turbulent enough to pull covering slag droplets down into the steel flow — an effect that gets worse whenever flow conditions change, such as during ladle exchanges. In a tundish without an effective barrier, that entrained slag has a clear path toward the outlets. Working together with our tundish impact pad and turbulence inhibitor assembly, a weir wall isolates that turbulence within the pour box and gives the steel an upward flow vector that encourages slag droplets and inclusions to float back to the surface before reaching the casting zone.

Heat-to-Heat Flow Inconsistency

Tundish bath level changes during sequence casting, and with each change the flow pattern shifts if there's no fixed flow-control structure to stabilize it. A properly designed weir wall maintains a consistent flow geometry across the full range of operational bath depths, giving each heat comparable opportunity for inclusion separation rather than leaving cleanliness to vary with operating conditions.

What a Weir Wall / Dam Block Actually Does Inside the Flow Path

Separating Pour Zone From Outlet Zone

The weir wall spans the width of the tundish, creating a physical division between the high-turbulence pour box and the calm casting zone where the outlets sit. Steel cannot travel in a straight line from the ladle shroud to the nozzles; it must pass through the engineered apertures in the block, which breaks up large eddies and converts chaotic turbulence into a controlled, forward-moving flow field.

Metered Flow Through Engineered Holes

Rather than simply damming the flow and forcing steel over the top — which can pull slag down with it — our blocks incorporate angled through-holes positioned to direct emerging steel upward toward the covering powder. The hole diameter, angle, and layout are calculated to maintain the required mass flow rate while ensuring the upward velocity component is sufficient to drive inclusion flotation across all operational casting speeds.

Reinforced Precast Construction for Installation Strength

A weir wall that cracks during installation or develops through-thickness fractures during preheat is worse than no wall at all — it leaks steel unpredictably and sheds refractory debris directly into the flow path. Our weir wall blocks are manufactured from low-cement corundum castable with cast-in stainless steel reinforcement, engineered to withstand crane handling, thermal shock during tundish preheating, and the mechanical forces of continuous steel flow.

Tundish flow section diagram with corundum weir wall dam block, angled flow holes, and steel inclusion flotation zone

Tundish flow section diagram with corundum weir wall dam block, angled flow holes, and steel inclusion flotation zone.

Corundum Grade — Why High-Alumina Chemistry at This Location

The dam wall sees a combination that most other tundish components don't: constant steel-flow impingement directly through the holes, plus the thermal cycling of every ladle change, at a component thickness too thin to rely on mass alone for thermal buffering the way a thick working lining can. A standard low/medium-alumina castable erodes at the hole edges faster than it wears on the flat faces, which widens the holes over the campaign and changes the metered flow pattern you designed for in the first place.

High-Velocity Orifice Erosion & Dimensional Retention

Corundum-grade castable (Al₂O₃ ≥ 85%) holds hole geometry and face dimension through the full campaign far better than lower-grade alternatives, which is why it's the grade we specify for this component even on tundish designs that use a more economical magnesia dry vibrating mix for the main working lining.

Thermal Cycling & Cold Crushing Strength under Thermal Shock

With cold crushing strengths exceeding 60 MPa after drying and 100 MPa after 1500°C firing, our dense corundum matrix exhibits exceptional mechanical rigidity. It prevents micro-cracking around hole perimeters under repetitive thermal shocks when molten steel levels fluctuate during ladle changeovers.

Precast Construction We Supply — Matched to Your Tundish Geometry

Dimensions and Hole Pattern Engineered to Your Flow Model

We don't sell off-the-shelf dam walls — each project starts from your tundish drawings, throughput rates, and strand count. If you have CFD flow modeling data, we build to that; if you don't, our engineering team will propose a hole pattern based on your tundish geometry and target steel grades.

Free Samples for Trial Before Volume Order

For qualified steel plants evaluating a supplier switch or designing a new tundish lining package, we supply sample blocks for hot-trial verification in your active casting sequence. You can verify fit, installation behavior, and post-campaign residual thickness before committing to volume procurement.

On-Site Engineer Support for Installation and Setting

Our technical service team can assist on-site during initial trial installations, advising your refractories crew on positioning, joint mortar application, and preheating ramp rates to ensure the block achieves its designed service life from the first sequence.

Technical Data Sheet — Corundum Weir Wall / Dam Block Castable

Indicative industry reference range — confirm exact figures against the mill test certificate/COA for your specific order.

Property Typical Value
Al₂O₃ Content ≥ 85%
SiO₂ Content ≤ 8%
CaO (Low-Cement Binder System) ≤ 2%
Bulk Density (110°C) ≥ 2.95 g/cm³
Bulk Density (1500°C) ≥ 3.05 g/cm³
Cold Crushing Strength (110°C) ≥ 60 MPa
Cold Crushing Strength (1500°C) ≥ 100 MPa
Apparent Porosity (1500°C) ≤ 18%
Linear Change (1500°C × 3h) ± 0.5%
Maximum Service Temperature 1750°C

Technical Procurement Specification Checklist for Continuous Casting Mills

Tundish Geometry & Casting Operational Parameters

Key Physical & Chemical Specification Matrix:

Standard Metallurgical Acceptance Checkpoints:
  • Tundish Flow Layout: Tundish drawing with pour box, outlet, and current flow-control layout (if any).
  • Throughput & Sequence: Tundish capacity, casting rate, and sequence length.
  • Steel Cleanliness Requirements: Steel grades cast and any grade-specific cleanliness requirements.
  • Nozzle Configuration: Number and position of outlet nozzles relative to the pour box.
  • Existing Design Parameters: Existing dam/weir design (if replacing) — dimensions, hole pattern, material grade.
  • Handling & Rigging: Installation method and lifting equipment available on-site.
  • Quality & Testing: Required TDS/COA confirmation format per batch or per shipment.

Frequently Asked Questions: Continuous Casting Refractory Teams (FAQ)

What is the difference between a weir wall and a dam block?

In practice the terms are often used for the same function — a flow-control barrier between the pour and outlet zones of the tundish. Some designs use a solid dam plus a separate weir to force an S-shaped flow path; the perforated single-wall design shown on this page achieves a similar flow-control effect through its angled hole pattern in one precast component.

How do tundish weir walls work together with impact pads and turbulence inhibitors?

Fluid control in a continuous casting tundish functions as a two-stage system: the tundish impact pad and turbulence inhibitor absorbs vertical kinetic energy at the pour box, redirecting flow upward and preventing slag entrainment at the source. The downstream perforated corundum weir wall then meters the horizontal flow velocity and forces steel toward the surface for non-metallic inclusion separation. Operating both components as a matched set provides optimal flow conditioning across all casting strands.

How do tundish weir walls work together with tundish covers and nozzles to improve steel cleanliness?

A weir wall directs liquid steel upward so non-metallic inclusions can float into the covering slag layer. However, if the tundish roof lacks an airtight thermal seal, atmospheric oxygen and nitrogen are drawn in, generating secondary reoxidation inclusions that undermine flotation gains. Installing our four-zone tundish cover castables eliminates air aspiration. Downstream, installing zirconia-core anti-clogging nozzles prevents residual alumina deposition, maintaining steady casting speed and ensuring clean steel flows into the continuous casting mold.

Can you match the dam wall to our existing tundish without a full redesign?

Yes — if you can share your current tundish drawing and the dimensions of any existing flow-control device, we can engineer a replacement to the same footprint or propose an improved hole pattern within the same installation envelope.

Why corundum instead of a standard castable for just this one component?

The holes are the highest-wear feature on the block — they see direct flow impingement rather than the general erosion a flat wall surface experiences. Corundum-grade castable holds hole geometry significantly longer, which matters because the flow-control benefit depends on the holes staying close to their designed dimension.

Do you supply the anchor loops and mortar, or just the precast block?

We can supply the complete installation package — precast block, cast-in anchors, and matched setting mortar — or the block alone if you're sourcing mortar locally.

How long does a corundum dam wall typically last?

Service life depends on your casting rate, steel grade, and sequence length — send us your working data and we'll give you a realistic estimate based on comparable installations rather than a generic figure.

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Request a Custom Tundish Weir Wall & Dam Block Proposal

Contact YK Chanshine technical engineers for custom hole pattern engineering, CFD flow recommendations, sample trial blocks, and comprehensive continuous casting turnaround quotations. Send your tundish capacity, throughput, and strand layout.

Direct Engineering Email: sales@ykchanshine.com | Plant Line: +86-139-9807-2158