---
title: "Brake Master Cylinder"
industry: "Motor Vehicle Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:BRAKE_MASTER_CYLINDER"
  data_integrity_hash: "119c9da52c2eda882c04c690aea5762e"
  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:BRAKE_MASTER_CYLINDER"
  data_source_uri: "https://cnfx.com/llms/industry/motor-vehicle-manufacturing/product/brake-master-cylinder.md"
  official_resource_url: "https://cnfx.com/industry/motor-vehicle-manufacturing/product/brake-master-cylinder"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "2.0-20.0 MPa"
    unit: "mm"
engineering_limits:
  max_safe_operating_point:
    value: 25.0
    unit: "MPa"
    consequence: "Seal extrusion failure due to exceeding 25.0 MPa yield strength of EPDM rubber seals (Shore A 70 hardness)"
fmea_matrix_quantitative:
  - node_1:
      trigger: "Brake fluid moisture absorption exceeding 3.0% water content"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Anodized aluminum cylinder bore with 25 μm hardcoat layer (MIL-A-8625 Type III)"
  - node_2:
      trigger: "Repeated thermal cycling between -40°C and 150°C"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Fluoroelastomer (FKM) seals with 70 durometer rating and -40°C to 200°C operating range"
bom_nodes:
  piston-assembly:
    type: "part"
    urn: "URN:CNFX:ME:PISTON_ASSEMBLY"
    interface_type: "physical-logic-coupled"
  reservoir:
    type: "part"
    urn: "URN:CNFX:ME:RESERVOIR"
    interface_type: "physical-logic-coupled"
  pushrod:
    type: "component"
    urn: "URN:CNFX:ME:PUSHROD"
    interface_type: "physical-logic-coupled"
  seals-and-cups:
    type: "component"
    urn: "URN:CNFX:ME:SEALS_AND_CUPS"
    interface_type: "physical-logic-coupled"
  springs:
    type: "component"
    urn: "URN:CNFX:ME:SPRINGS"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
url: "https://cnfx.com/llms/industry/motor-vehicle-manufacturing/product/brake-master-cylinder.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "338d11d4fad3fabe36344f9688aa3decd4059e11f74b1510dac74518e66f7946"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Brake Master Cylinder

## 1. Technical Definition
Hydraulic pressure generator for brake systems

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **2.0-20.0 MPa**. Failure boundary: **25.0 MPa internal pressure causing permanent seal deformation**, Mechanism: **Seal extrusion failure due to exceeding 25.0 MPa yield strength of EPDM rubber seals (Shore A 70 hardness)**.

### 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 |
| :--- | :--- | :--- | :--- |
| Brake fluid moisture absorption exceeding 3.0% water content | 8 | Internal corrosion of aluminum cylinder bore (pitting depth &gt;0.5 mm) | Anodized aluminum cylinder bore with 25 μm hardcoat layer (MIL-A-8625 Type III) |
| Repeated thermal cycling between -40°C and 150°C | 8 | Seal hardening and cracking (Shore A hardness increase &gt;15 points) | Fluoroelastomer (FKM) seals with 70 durometer rating and -40°C to 200°C operating range |

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

## 4. System BOM & Knowledge Routing
### Core Components (Recursive Links)
- [Piston Assembly](https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/piston-assembly.md) `(Standalone System)`
- [Reservoir](https://cnfx.com/llms/industry/motor-vehicle-manufacturing/product/reservoir.md) `(Standalone System)`

### Industrial DNA Context (De-duplicated)
**Complementary Dependencies**: **Hydraulic Power Unit**, **CNC Machining Center**, **Automated Assembly Line**  
**Downstream Applications**: Passenger Vehicle Brake System, Commercial Vehicle Brake System, Motorcycle Brake System  

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

### Q: What are the main materials used in this brake master cylinder?
**A**: This brake master cylinder is constructed from high-quality aluminum alloy for the body, cast iron for durability in critical components, and steel for internal parts like the pushrod and springs, ensuring longevity and reliable performance.

### Q: How do I know if my brake master cylinder needs replacement?
**A**: Common signs include a spongy or sinking brake pedal, visible fluid leaks near the cylinder, contaminated brake fluid, or the brake warning light illuminating. Regular inspection of the reservoir fluid level and seal condition is recommended.

### Q: What is included in the BOM (Bill of Materials) for this brake master cylinder?
**A**: The BOM includes the piston assembly for pressure generation, reservoir for brake fluid storage, pushrod for actuation, seals and cups to prevent leaks, and springs for return motion, ensuring complete functionality in hydraulic brake systems.

## 6. Manufacturing Compliance

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### 🛠️ Engineering Resource Access
🔗 **[Full Specification: Brake Master Cylinder](https://cnfx.com/industry/motor-vehicle-manufacturing/product/brake-master-cylinder)**

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

> **Reference ID**: BRAKE_MASTER_CYLINDER | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: fdad01b8
