---
title: "Rail Pipe"
industry: "Motor Vehicle Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:RAIL_PIPE"
  data_integrity_hash: "e1ff9a2ff1d2a5e42f96acac20b26ce2"
  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:RAIL_PIPE"
  data_source_uri: "https://cnfx.com/llms/industry/motor-vehicle-manufacturing/product/rail-pipe.md"
  official_resource_url: "https://cnfx.com/industry/motor-vehicle-manufacturing/product/rail-pipe"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "1500-2500 bar"
    unit: "mm"
engineering_limits:
  max_safe_operating_point:
    value: 2800
    unit: "bar"
    consequence: "High-cycle fatigue from pressure pulsations at 2-10 Hz frequency, combined with stress corrosion cracking from sulfur compounds in ULSD fuel"
fmea_matrix_quantitative:
  - node_1:
      trigger: "Resonant vibration at 120 Hz matching engine firing frequency"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Helical damping coil insert with 0.8 mm wire diameter and 12 mm pitch"
  - node_2:
      trigger: "Fuel temperature exceeding 130°C causing viscosity drop to 1.2 cSt"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Integral pulsation damper with 15 cm³ accumulator volume and 0.5 mm orifice"
bom_nodes:
  pipe-body:
    type: "component"
    urn: "URN:CNFX:ME:PIPE_BODY"
    interface_type: "physical-logic-coupled"
  connection-fittings:
    type: "part"
    urn: "URN:CNFX:ME:CONNECTION_FITTINGS"
    interface_type: "physical-logic-coupled"
  protective-coating:
    type: "component"
    urn: "URN:CNFX:ME:PROTECTIVE_COATING"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
  - standard: "ISO 9001:2015 - QUALITY MANAGEMENT SYSTEMS"
    scope: "Verified Engineering Specification"
  - standard: "EN 10219-1:2006 - COLD FORMED WELDED STRUCTURAL HOLLOW SECTIONS OF NON-ALLOY AND FINE GRAIN STEELS"
    scope: "Verified Engineering Specification"
url: "https://cnfx.com/llms/industry/motor-vehicle-manufacturing/product/rail-pipe.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "1a7daa1dd6cde85454dd4c090643a3aeed60af0a3705b7825e2e00ccb755faac"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Rail Pipe

## 1. Technical Definition
A high-pressure pipe that distributes fuel from the common rail to individual injectors in a diesel engine's fuel injection system.

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **1500-2500 bar**. Failure boundary: **2800 bar (yield strength of SAE 4140 steel at 150°C)**, Mechanism: **High-cycle fatigue from pressure pulsations at 2-10 Hz frequency, combined with stress corrosion cracking from sulfur compounds in ULSD fuel**.

### 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 |
| :--- | :--- | :--- | :--- |
| Resonant vibration at 120 Hz matching engine firing frequency | 8 | Fatigue crack initiation at pipe-to-fitting weld joint | Helical damping coil insert with 0.8 mm wire diameter and 12 mm pitch |
| Fuel temperature exceeding 130°C causing viscosity drop to 1.2 cSt | 8 | Hydraulic hammer pressure spikes reaching 3200 bar during injector closure | Integral pulsation damper with 15 cm³ accumulator volume and 0.5 mm orifice |

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

## 4. System BOM & Knowledge Routing
### Core Components (Recursive Links)
- [Connection fittings](https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/connection-fittings.md) `(Standalone System)`

### Industrial DNA Context (De-duplicated)
**Complementary Dependencies**: **High-Pressure Tube Bender**, **CNC Tube Cutting Machine**, **Automated Leak Testing System**  
**Downstream Applications**: Common Rail Fuel Injection System, Diesel Engine Assembly, Complete Motor Vehicle  

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

### Q: What is the primary function of a rail pipe in diesel engines?
**A**: The rail pipe distributes high-pressure fuel from the common rail to individual injectors, ensuring precise fuel delivery for optimal combustion in diesel engines.

### Q: Why is high-strength steel alloy used for rail pipes?
**A**: High-strength steel alloy withstands extreme pressures in diesel fuel injection systems, prevents leaks, and resists corrosion for long-term durability in motor vehicles.

### Q: How does the protective coating benefit the rail pipe?
**A**: The protective coating shields the steel alloy from environmental factors like moisture and chemicals, reducing wear and extending the pipe's service life in vehicle manufacturing.

## 6. Manufacturing Compliance
- ISO 9001:2015 - QUALITY MANAGEMENT SYSTEMS
- EN 10219-1:2006 - COLD FORMED WELDED STRUCTURAL HOLLOW SECTIONS OF NON-ALLOY AND FINE GRAIN STEELS

---
### 🛠️ Engineering Resource Access
🔗 **[Full Specification: Rail Pipe](https://cnfx.com/industry/motor-vehicle-manufacturing/product/rail-pipe)**

### 🌐 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**: RAIL_PIPE | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: b1949a88
