Flange Bolts - Pumps, Valves, Piping and Fittings
Flange bolts are hexagon-head fasteners with an integral flange that distributes clamping load over a wider area. In marine pumps, valves, piping and fittings, they are selected by diameter, thread, strength grade, material, coating and corrosion environment.
ProShipWorks provides end-to-end support to source and supply Flange Bolts for marine vessels, ship operators, industrial facilities, maintenance teams and procurement departments.
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Product Information
| Product Name | Flange Bolts |
|---|---|
| Product Category | Pumps, Valves, Piping and Fittings |
| Product Reference | 644 |
| Brands / Manufacturers | Würth, Bossard, Unbrako |
| Unit of Measure | Piece |
Key Features
| Key Feature |
|---|
| 1. Integral washer-like flange under the bolt head |
| 2. Available in metric and imperial thread sizes |
| 3. Common strength grades include ISO 898-1 classes 8.8 and 10.9 |
| 4. Stainless steel, galvanized and coated steel options |
| 5. Suitable for bolted pump, valve, pipe and fitting connections |
Applications of Flange Bolts
| Application |
|---|
| 1. Mounting and securing marine pumps and pump accessories |
| 2. Bolted connections for valves, pipe flanges and fittings |
| 3. Equipment foundations, brackets and machinery support assemblies |
Models & Manufacturers
| Model | Manufacturer |
|---|---|
| Hexagon flange bolt, ISO 4162 | Various qualified fastener manufacturers |
| Hexagon flange bolt, DIN 6921 | Various qualified fastener manufacturers |
Technical Specifications
| Model | Specification | Value | Unit |
|---|---|---|---|
| ISO 4162 flange bolt | Strength class | 8.8, 10.9 or as specified | — |
| ISO 4162 flange bolt | Material | Carbon steel, alloy steel or stainless steel | — |
| ISO 4162 flange bolt | Thread | Metric coarse thread, typically M6 to M24 | — |
| ISO 4162 flange bolt | Surface protection | Zinc plated, hot-dip galvanized, marine coating or plain | — |
| ISO 4162 flange bolt | Stainless material grades | A2-70 or A4-70/A4-80 where specified | — |
Standards, Certifications & Class Approval
Review the available standards and approval information relevant to the product. Actual certification, material traceability, inspection and classification requirements depend on the product type, intended application and purchasing specification.
| Applicable Standards & Certification | Common dimensional standards include ISO 4162 and DIN 6921. Mechanical properties may comply with ISO 898-1 for carbon and alloy steel fasteners. Stainless fasteners may comply with ISO 3506-1. Material certificates such as EN 10204 3.1 may be required for critical marine installations. |
|---|---|
| Class Approval | Individual flange bolts do not normally carry separate type approval. For classed vessels, fasteners may require material certification, traceability and compliance with the applicable DNV, ABS, Lloyd's Register, Bureau Veritas or other classification-society rules. |
Installation, Maintenance & Safety Information
| Installation Notes | Verify diameter, thread, length, grade, material and coating against the equipment drawing and flange specification. Use compatible nuts and washers where required. Clean mating threads and tighten in the specified cross-pattern and torque sequence using a calibrated tool. |
|---|---|
| Maintenance Tips | Inspect for corrosion, looseness, damaged threads and loss of coating during planned maintenance. Check critical bolted joints for correct torque according to the maker's procedure. Replace bolts showing deformation, severe corrosion or damaged threads; do not mix incompatible stainless and carbon-steel hardware without corrosion controls. |
| Safety Notes | Use only the specified strength grade and material. Do not substitute ordinary bolts for pressure-boundary or machinery fasteners. Depressurize, drain and isolate piping or equipment before loosening bolts. Follow approved torque values and use suitable personal protective equipment. |
Request a Quote for Flange Bolts
Contact ProShipWorks for marine or industrial product sourcing, quotations and delivery.
- Vessel name and IMO number
- ETA / vessel schedule
- Berth or vessel location
- Required quantity
- Preferred delivery window
- Shipping agent contact details
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