---
title: "Tank Structure"
industry: "Other Transport Equipment Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:TANK_STRUCTURE"
  data_integrity_hash: "f8be5090fabcc0eadd475f45ebf9ae21"
  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:TANK_STRUCTURE"
  data_source_uri: "https://cnfx.com/llms/industry/other-transport-equipment-manufacturing/product/tank-structure.md"
  official_resource_url: "https://cnfx.com/industry/other-transport-equipment-manufacturing/product/tank-structure"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "0-0.3 bar (gauge pressure) for atmospheric ballast tanks, 0-2.0 bar for pressurized ballast systems"
    unit: "mm"
engineering_limits:
  max_safe_operating_point:
    value: 355
    unit: "MPa"
    consequence: "Stress corrosion cracking in seawater environment (chloride-induced), particularly at stress concentrations exceeding 0.6σ_y, combined with cyclic loading from wave-induced hull bending moments (typically 10^6-10^8 cycles over vessel lifespan)"
fmea_matrix_quantitative:
  - node_1:
      trigger: "Corrosion rate exceeding 0.1 mm/year in seawater due to inadequate cathodic protection (potential below -0.85V vs Ag/AgCl reference)"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Implementation of impressed current cathodic protection system maintaining -0.95 to -1.05V potential, combined with 3 mm corrosion allowance in structural design"
  - node_2:
      trigger: "Resonant vibration at natural frequency of tank structure (typically 8-15 Hz) matching main engine excitation frequencies"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Structural stiffener redesign to shift natural frequency above 20 Hz, combined with post-weld toe grinding to reduce stress concentration factors below 1.8"
bom_nodes:
  tank-shell-plates:
    type: "component"
    urn: "URN:CNFX:ME:TANK_SHELL_PLATES"
    interface_type: "physical-logic-coupled"
  stiffeners:
    type: "component"
    urn: "URN:CNFX:ME:STIFFENERS"
    interface_type: "physical-logic-coupled"
  welded-joints:
    type: "component"
    urn: "URN:CNFX:ME:WELDED_JOINTS"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
url: "https://cnfx.com/llms/industry/other-transport-equipment-manufacturing/product/tank-structure.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "3520d40e93bf3cc66aa2984fd743777658c4a46783ac22a2248d3574a1f9a019"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Tank Structure

## 1. Technical Definition
The structural framework and containment system of ballast tanks in marine vessels.

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **0-0.3 bar (gauge pressure) for atmospheric ballast tanks, 0-2.0 bar for pressurized ballast systems**. Failure boundary: **Yield stress of structural steel (typically 250-355 MPa) exceeded, or fatigue crack propagation reaching critical length (typically 25-40 mm in marine-grade steel)**, Mechanism: **Stress corrosion cracking in seawater environment (chloride-induced), particularly at stress concentrations exceeding 0.6σ_y, combined with cyclic loading from wave-induced hull bending moments (typically 10^6-10^8 cycles over vessel lifespan)**.

### 2.1 Analytical Physics Model
Governed by the **Thin-Wall Pressure Vessel Stress Analysis**:

> **Primary Equation**: $\sigma_h = \frac{P \cdot D}{2t}$  
> **Engineering Impact**: Determines the hoop stress boundary to prevent rupture.

| Symbol | Variable Definition | Localized Reference |
| :--- | :--- | :--- |
| P | Internal Pressure | Engineering Constant |
| D | Diameter | Engineering Constant |
| t | Wall Thickness | Engineering Constant |

### 2.2 FMEA (Failure Mode & Effects Analysis)
| Event Trigger | Severity | Failure Mode | Mitigation Strategy |
| :--- | :--- | :--- | :--- |
| Corrosion rate exceeding 0.1 mm/year in seawater due to inadequate cathodic protection (potential below -0.85V vs Ag/AgCl reference) | 8 | Localized wall thinning below minimum thickness requirement (typically 6-12 mm for marine steel plates), leading to structural buckling under hydrostatic load | Implementation of impressed current cathodic protection system maintaining -0.95 to -1.05V potential, combined with 3 mm corrosion allowance in structural design |
| Resonant vibration at natural frequency of tank structure (typically 8-15 Hz) matching main engine excitation frequencies | 8 | High-cycle fatigue failure initiating at weld toe locations where stress concentration factors exceed 2.5 | Structural stiffener redesign to shift natural frequency above 20 Hz, combined with post-weld toe grinding to reduce stress concentration factors below 1.8 |

## 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**: **Welding Positioner**, **Shot Blasting Machine**, **Coordinate Measuring Machine (CMM)**  
**Downstream Applications**: Ballast Tank System, Marine Vessel Hull Section, Integrated Ballast Water Management System  

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

### Q: What materials are used in tank structures for marine ballast systems?
**A**: Tank structures for marine ballast systems are constructed from marine-grade steel, which offers superior corrosion resistance and durability in harsh marine environments.

### Q: What components are included in the BOM for a ballast tank structure?
**A**: The bill of materials includes stiffeners for structural support, tank shell plates for containment, and welded joints to ensure watertight integrity and structural stability.

### Q: How do tank structures contribute to vessel stability and safety?
**A**: Tank structures provide the essential framework for ballast systems, allowing precise weight distribution to maintain vessel stability, trim, and safety during various operating conditions.

## 6. Manufacturing Compliance

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### 🛠️ Engineering Resource Access
🔗 **[Full Specification: Tank Structure](https://cnfx.com/industry/other-transport-equipment-manufacturing/product/tank-structure)**

### 🌐 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**: TANK_STRUCTURE | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: ecc25d32
