---
title: "Hydraulic Cylinders"
industry: "Machinery and Equipment Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:HYDRAULIC_CYLINDERS"
  data_integrity_hash: "0ef8d027fa80a4f2b387abeb3cbc6859"
  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:HYDRAULIC_CYLINDERS"
  data_source_uri: "https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/hydraulic-cylinders.md"
  official_resource_url: "https://cnfx.com/industry/machinery-and-equipment-manufacturing/product/hydraulic-cylinders"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "1.5-350 MPa (15-3500 bar)"
    unit: "mm"
engineering_limits:
  max_safe_operating_point:
    value: 1.2
    unit: "x"
    consequence: "Seal extrusion failure occurs when fluid pressure exceeds seal material's extrusion resistance modulus (typically 0.8-1.2 GPa for polyurethane), causing material flow into clearance gaps. Piston rod buckling follows Euler's formula: F_critical = (π²EI)/(KL)² where E=210 GPa for steel, I=πd⁴/64, K=2 for fixed-free end conditions. Barrel yield occurs when hoop stress σ_θ = (p·D)/(2t) exceeds material yield strength (typically 250-550 MPa for steel cylinders)."
fmea_matrix_quantitative:
  - node_1:
      trigger: "Fluid contamination exceeding ISO 4406 18/16/13 cleanliness level"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Install 3 μm absolute filtration with β₃≥200 rating and implement real-time particle counting with automatic bypass at 22/20/17 contamination level"
  - node_2:
      trigger: "Hydraulic fluid temperature exceeding 82°C for mineral oil or 135°C for synthetic ester"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Integrate PID-controlled cooling system with thermal cutoff at 75°C (mineral) or 120°C (synthetic), using NTC thermistors with ±0.5°C accuracy"
bom_nodes:
  cylinder-barrel:
    type: "part"
    urn: "URN:CNFX:ME:CYLINDER_BARREL"
    interface_type: "physical-logic-coupled"
  piston:
    type: "part"
    urn: "URN:CNFX:ME:PISTON"
    interface_type: "physical-logic-coupled"
  piston-rod:
    type: "component"
    urn: "URN:CNFX:ME:PISTON_ROD"
    interface_type: "physical-logic-coupled"
  end-caps:
    type: "component"
    urn: "URN:CNFX:ME:END_CAPS"
    interface_type: "physical-logic-coupled"
  seals:
    type: "component"
    urn: "URN:CNFX:ME:SEALS"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
url: "https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/hydraulic-cylinders.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "74836e665f24d9ecdddedb9726b47a8aa71eb0245e069c53920b7edb569a7400"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Hydraulic Cylinders

## 1. Technical Definition
Hydraulic actuators that convert fluid pressure into linear mechanical force and motion.

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **1.5-350 MPa (15-3500 bar)**. Failure boundary: **Seal extrusion at 1.2x maximum rated pressure (e.g., 420 MPa for 350 MPa rated cylinder), piston rod buckling at 0.8x Euler critical load, cylinder barrel yield at 1.5x yield strength**, Mechanism: **Seal extrusion failure occurs when fluid pressure exceeds seal material's extrusion resistance modulus (typically 0.8-1.2 GPa for polyurethane), causing material flow into clearance gaps. Piston rod buckling follows Euler's formula: F_critical = (π²EI)/(KL)² where E=210 GPa for steel, I=πd⁴/64, K=2 for fixed-free end conditions. Barrel yield occurs when hoop stress σ_θ = (p·D)/(2t) exceeds material yield strength (typically 250-550 MPa for steel cylinders).**.

### 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 |
| :--- | :--- | :--- | :--- |
| Fluid contamination exceeding ISO 4406 18/16/13 cleanliness level | 8 | Seal abrasive wear causing internal leakage exceeding 5% of rated flow | Install 3 μm absolute filtration with β₃≥200 rating and implement real-time particle counting with automatic bypass at 22/20/17 contamination level |
| Hydraulic fluid temperature exceeding 82°C for mineral oil or 135°C for synthetic ester | 8 | Seal material degradation (hardness change &gt;10 Shore A) leading to extrusion failure at 85% rated pressure | Integrate PID-controlled cooling system with thermal cutoff at 75°C (mineral) or 120°C (synthetic), using NTC thermistors with ±0.5°C accuracy |

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

## 4. System BOM & Knowledge Routing
### Core Components (Recursive Links)
- [Cylinder Barrel](https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/cylinder-barrel.md) `(Standalone System)`
- [Piston](https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/piston.md) `(Standalone System)`

### Industrial DNA Context (De-duplicated)
**Complementary Dependencies**: **Hydraulic Power Unit**, **Hydraulic Fluid Filtration System**, **Pressure Control Valves**  
**Downstream Applications**: Excavators, Industrial Presses, Aircraft Landing Gear  

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

### Q: What materials are used in your hydraulic cylinders for maximum durability?
**A**: Our hydraulic cylinders are constructed from high-strength alloy steel barrels, chromium-plated steel rods for corrosion resistance, and polyurethane seals for optimal performance in demanding industrial environments.

### Q: How do I determine the right hydraulic cylinder specifications for my machinery?
**A**: Key specifications include bore size, stroke length, operating pressure, and mounting style. We recommend consulting with our engineering team to match cylinder specs to your specific application requirements and load conditions.

### Q: What maintenance is required for hydraulic cylinders in manufacturing equipment?
**A**: Regular maintenance includes inspecting seals for wear, checking rod surfaces for damage, monitoring fluid cleanliness, and ensuring proper alignment. Our cylinders are designed with replaceable components like seals and end caps for easy servicing.

## 6. Manufacturing Compliance

---
### 🛠️ Engineering Resource Access
🔗 **[Full Specification: Hydraulic Cylinders](https://cnfx.com/industry/machinery-and-equipment-manufacturing/product/hydraulic-cylinders)**

### 🌐 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**: HYDRAULIC_CYLINDERS | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: 14f3de3f
