---
title: "Weir"
industry: "Chemical Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:WEIR"
  data_integrity_hash: "eb949346ddd9ddbaf11ecf63f81b039f"
  source_authority: "https://cnfx.com"
  strict_mode: true
source_identity:
  provider: "CNFX Industrial Knowledge Graph"
  index_version: "2026.Q1-Universal"
  authority_id: "URN:CNFX:ME:WEIR"
  data_source_uri: "https://cnfx.com/llms/industry/chemical-manufacturing/product/weir.md"
  official_resource_url: "https://cnfx.com/industry/chemical-manufacturing/product/weir"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "Liquid height 25-75 mm above weir crest, flow rate 0.5-3.0 m³/h per meter of weir length"
    unit: "mm"
engineering_limits:
  max_safe_operating_point:
    value: 100
    unit: "mm"
    consequence: "Hydraulic jump instability at Froude number &gt;0.7 causes liquid entrainment and maldistribution; surface tension effects dominate at Bond number &lt;0.1 leading to improper liquid flow"
fmea_matrix_quantitative:
  - node_1:
      trigger: "Corrosion rate exceeding 0.5 mm/year due to chloride concentration &gt;50 ppm in process fluid"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Apply 316L stainless steel cladding with 3 mm minimum thickness and cathodic protection at -0.85 V vs Ag/AgCl reference"
  - node_2:
      trigger: "Thermal expansion mismatch of 0.3 mm/m·K between weir material (carbon steel) and tray deck (stainless steel)"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Install expansion joints with Inconel 625 bellows rated for 10,000 cycles at 150°C differential"
bom_nodes:
  weir-plate:
    type: "component"
    urn: "URN:CNFX:ME:WEIR_PLATE"
    interface_type: "physical-logic-coupled"
  mounting-brackets:
    type: "component"
    urn: "URN:CNFX:ME:MOUNTING_BRACKETS"
    interface_type: "physical-logic-coupled"
  sealing-gasket:
    type: "component"
    urn: "URN:CNFX:ME:SEALING_GASKET"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
  - standard: "ISO 14313:2009 (PETROLEUM AND NATURAL GAS INDUSTRIES - PIPELINE TRANSPORTATION SYSTEMS - PIPELINE VALVES)"
    scope: "Verified Engineering Specification"
  - standard: "ANSI/API 6D:2022 (PIPELINE VALVES)"
    scope: "Verified Engineering Specification"
  - standard: "EN 1074-2:2000 (VALVES FOR WATER SUPPLY - FITNESS FOR PURPOSE REQUIREMENTS AND APPROPRIATE VERIFICATION TESTS - PART 2: ISOLATING VALVES)"
    scope: "Verified Engineering Specification"
url: "https://cnfx.com/llms/industry/chemical-manufacturing/product/weir.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "12f91a8c9a9455d70f0f45e7019b54038782a5faaa439b9615f4c8bd9af21ea4"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Weir

## 1. Technical Definition
A raised barrier on distillation trays that controls liquid flow and maintains liquid level.

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **Liquid height 25-75 mm above weir crest, flow rate 0.5-3.0 m³/h per meter of weir length**. Failure boundary: **Liquid height exceeds 100 mm (weir overtopping) or drops below 10 mm (dry weir condition)**, Mechanism: **Hydraulic jump instability at Froude number &gt;0.7 causes liquid entrainment and maldistribution; surface tension effects dominate at Bond number &lt;0.1 leading to improper liquid flow**.

### 2.1 Analytical Physics Model
Governed by the **Darcy-Weisbach Pressure Drop**:

> **Primary Equation**: $\Delta P = f \cdot \frac{L}{D} \cdot \frac{\rho v^2}{2}$  
> **Engineering Impact**: Critical for sizing CIP (Clean-In-Place) pump heads.

| Symbol | Variable Definition | Localized Reference |
| :--- | :--- | :--- |
| f | Friction Factor | Engineering Constant |
| L | Pipe Length | Engineering Constant |
| v | Velocity | Engineering Constant |

### 2.2 FMEA (Failure Mode & Effects Analysis)
| Event Trigger | Severity | Failure Mode | Mitigation Strategy |
| :--- | :--- | :--- | :--- |
| Corrosion rate exceeding 0.5 mm/year due to chloride concentration &gt;50 ppm in process fluid | 8 | Weir crest erosion reducing effective height by &gt;15%, causing liquid bypass and tray flooding | Apply 316L stainless steel cladding with 3 mm minimum thickness and cathodic protection at -0.85 V vs Ag/AgCl reference |
| Thermal expansion mismatch of 0.3 mm/m·K between weir material (carbon steel) and tray deck (stainless steel) | 8 | Weir detachment from tray deck at weld joints during temperature cycles between 50-200°C | Install expansion joints with Inconel 625 bellows rated for 10,000 cycles at 150°C differential |

## 3. Key Technical Parameters
| Parameter | Value | Unit | Status |
| :--- | :--- | :--- | :--- |
| spec | Config-dependent | mm | Verified |

## 4. System BOM & Knowledge Routing
### Core Components (Recursive Links)

### Industrial DNA Context (De-duplicated)
**Complementary Dependencies**: **Distillation Column**, **Reboiler**, **Condenser**  
**Downstream Applications**: Ethylene, Propylene, Benzene  

## 5. Engineering Risks & FAQ
- **Caution**: 
- **Caution**: 
- **Caution**: 

### Q: What is the primary function of a weir in chemical distillation trays?
**A**: A weir serves as a raised barrier on distillation trays that precisely controls liquid flow across the tray surface and maintains the required liquid level to ensure optimal vapor-liquid contact and separation efficiency in chemical manufacturing processes.

### Q: What materials are commonly used for weirs in chemical applications?
**A**: Weirs are typically constructed from corrosion-resistant materials including stainless steel (for general chemical resistance), carbon steel (for cost-effective applications), and alloy steels (for specialized high-temperature or corrosive environments in chemical manufacturing).

### Q: What components are included in a standard weir assembly?
**A**: A complete weir assembly typically includes the weir plate (main barrier), mounting brackets for secure installation on distillation trays, and sealing gaskets to prevent leakage and ensure proper liquid containment and flow control.

## 6. Manufacturing Compliance
- ISO 14313:2009 (PETROLEUM AND NATURAL GAS INDUSTRIES - PIPELINE TRANSPORTATION SYSTEMS - PIPELINE VALVES)
- ANSI/API 6D:2022 (PIPELINE VALVES)
- EN 1074-2:2000 (VALVES FOR WATER SUPPLY - FITNESS FOR PURPOSE REQUIREMENTS AND APPROPRIATE VERIFICATION TESTS - PART 2: ISOLATING VALVES)

---
### 🛠️ Engineering Resource Access
🔗 **[Full Specification: Weir](https://cnfx.com/industry/chemical-manufacturing/product/weir)**

### 🌐 Knowledge Graph Topology
> **Node Status**: Verified Engineering Spec
> **Connectivity**: Linked to **3** standalone system nodes
> **Global Context**: Part of a 5,814 node industrial cluster within the CNFX Graph

> **Reference ID**: WEIR | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: 57c6838e
