---
title: "Manway"
industry: "Machinery and Equipment Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:MANWAY"
  data_integrity_hash: "a0ada16c7c1f770565530923b630e693"
  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:MANWAY"
  data_source_uri: "https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/manway.md"
  official_resource_url: "https://cnfx.com/industry/machinery-and-equipment-manufacturing/product/manway"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "0-25 bar differential pressure"
    unit: "mm"
engineering_limits:
  max_safe_operating_point:
    value: 35
    unit: "bar"
    consequence: "Bolted flange joint failure due to gasket relaxation and bolt creep under sustained pressure and thermal cycling, following ASME BPVC Section VIII Division 1 Appendix 2 flange design rules"
fmea_matrix_quantitative:
  - node_1:
      trigger: "Corrosive process fluid with chloride concentration exceeding 50 ppm at temperatures above 60°C"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Replace with duplex stainless steel UNS S32205 with PREN &gt;40 and implement cathodic protection system"
  - node_2:
      trigger: "Thermal cycling between 20°C and 180°C at frequency exceeding 3 cycles/hour"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Install flexible graphite spiral-wound gasket with Inconel 718 windings and torque monitoring system maintaining 70-80% of bolt yield strength"
bom_nodes:
  manway-cover:
    type: "component"
    urn: "URN:CNFX:ME:MANWAY_COVER"
    interface_type: "physical-logic-coupled"
  gasket:
    type: "component"
    urn: "URN:CNFX:ME:GASKET"
    interface_type: "physical-logic-coupled"
  hinge-or-hinges:
    type: "component"
    urn: "URN:CNFX:ME:HINGE_OR_HINGES"
    interface_type: "physical-logic-coupled"
  boltsnuts:
    type: "component"
    urn: "URN:CNFX:ME:BOLTSNUTS"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
  - standard: "ISO 9001:2015 QUALITY MANAGEMENT SYSTEMS"
    scope: "Verified Engineering Specification"
url: "https://cnfx.com/llms/industry/machinery-and-equipment-manufacturing/product/manway.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "70842856afab30a9700f19323cfd362f119b01f25c450b436e4a4f69ec2f582c"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Manway

## 1. Technical Definition
A sealed access opening in a pressure vessel for inspection, maintenance, and cleaning.

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **0-25 bar differential pressure**. Failure boundary: **35 bar differential pressure or 150°C temperature differential across sealing surfaces**, Mechanism: **Bolted flange joint failure due to gasket relaxation and bolt creep under sustained pressure and thermal cycling, following ASME BPVC Section VIII Division 1 Appendix 2 flange design rules**.

### 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 |
| :--- | :--- | :--- | :--- |
| Corrosive process fluid with chloride concentration exceeding 50 ppm at temperatures above 60°C | 8 | Stress corrosion cracking in 316L stainless steel flange material initiating at bolt holes | Replace with duplex stainless steel UNS S32205 with PREN &gt;40 and implement cathodic protection system |
| Thermal cycling between 20°C and 180°C at frequency exceeding 3 cycles/hour | 8 | Gasket compression loss due to differential thermal expansion between flange (carbon steel, α=11.7×10⁻⁶/°C) and bolts (alloy steel, α=13.0×10⁻⁶/°C) | Install flexible graphite spiral-wound gasket with Inconel 718 windings and torque monitoring system maintaining 70-80% of bolt yield strength |

## 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**: **Pressure Vessel**, **Gasket Sealing System**, **Bolting Torque Equipment**  
**Downstream Applications**: Chemical Reactors, Storage Tanks, Process Vessels  

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

### Q: What materials are available for industrial manways?
**A**: Our manways are manufactured in carbon steel, stainless steel, and alloy steel to suit various pressure vessel requirements and environmental conditions.

### Q: What components are included in a standard manway assembly?
**A**: A complete manway assembly typically includes the manway cover, bolts/nuts for secure fastening, a sealing gasket, and hinges for easy access during inspection and maintenance.

### Q: How do I select the right manway for my pressure vessel?
**A**: Selection depends on vessel pressure rating, operating temperature, material compatibility with contents, and required access size. Consult our specifications for pressure ratings and dimensional data.

## 6. Manufacturing Compliance
- ISO 9001:2015 QUALITY MANAGEMENT SYSTEMS

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

### 🌐 Knowledge Graph Topology
> **Node Status**: Verified Engineering Spec
> **Connectivity**: Linked to **4** standalone system nodes
> **Global Context**: Part of a 5,814 node industrial cluster within the CNFX Graph

> **Reference ID**: MANWAY | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: 8c442e67
