Marine Foundation Bolt & Engine Hold-down Bolt

sinofastener supplies marine foundation boltsandengine hold-down bolts for the installation of main engines, auxiliary generators, pump sets, compressors, and other critical rotating equipment aboard ships and offshore platforms. Our foundation bolts are manufactured in accordance with ASTM F1554 (Standard Specification for Anchor Bolts), ASTM A36 (Standard Specification for Carbon Structural Steel), and ASTM A193 (Alloy-Steel Bolting for High Temperature or High Pressure Service), covering sizes from M24 to M64 with lengths up to 3000mm. Products are manufactured to meet the material and mechanical requirements specified by classification society rules including ABS, DNV, LR, and CCS. EN 10204 3.1 material certificates are provided as standard, and third-party inspection can be coordinated upon request.

What Is a Marine Foundation Bolt?

Amarine foundation bolt (also referred to as an engine hold-down boltormarine anchor bolt) is a high-strength steel fastener used to secure heavy marine machinery to the ship's structural foundation. Per ASTM F1554, anchor bolts are defined as"steel bolts intended for anchoring structural supports and other objects to concrete foundations."In marine applications, these bolts are cast into or grouted within concrete or steel foundations, providing a permanent, vibration-resistant anchor point for equipment mounting.

The bolt assembly typically consists of a threaded rod with a bent end (L-shape or J-hook per ASTM F1554 Section 4.2) or a forged anchor head, paired with a base plate,leveling nuts, and washers. The upper threaded portion engages with the equipment mounting flange, while the lower anchor portion transfers tensile and shear loads into the foundation structure.

Marine Applications

Note: The bolt size and grade recommendations below are based on typical industry practice for marine engine room installations. Actual selection shall be determined by the equipment manufacturer's specification and the classification society requirements applicable to the vessel.

Specifications & Materials

Why Choose sinofastener for Marine Foundation Bolts?

Standards Reference

• ASTM F1554 - Standard Specification for Anchor Bolts, Steel, 36, 55, and 105-Ksi Yield Strength
• ASTM A36/A36M - Standard Specification for Carbon Structural Steel
• ASTM A193/A193M - Standard Specification for Alloy-Steel and Stainless Steel Bolting for High Temperature or High Pressure Service
• ASTM A194/A194M - Standard Specification for Carbon and Alloy Steel Nuts for Bolts for High Pressure or High Temperature Service
• ISO 898-1 - Mechanical Properties of Fasteners Made of Carbon Steel and Alloy Steel - Part 1: Bolts, Screws and Studs
• ISO 1461 - Hot Dip Galvanized Coatings on Fabricated Iron and Steel Articles - Specifications and Test Methods
• ISO 4014 - Hex Head Bolts - Product Grades A and B
• ISO 4017 - Hex Head Screws - Product Grades A and B
• EN 10204:2004 - Metallic Products - Types of Inspection Documents

FAQ

What is the difference between a foundation bolt and a stud bolt?

Afoundation bolt is defined per ASTM F1554 as an anchor bolt designed to be embedded in concrete or grouted into steel foundations, featuring an anchor end (L-bend, J-hook, or forged head). A stud bolt is a fully threaded fastener used for flange connections per ASME B16.5. Foundation bolts resist pull-out and shear forces from equipment vibration; stud bolts resist internal pressure on flange joints.

Which ASTM F1554 grade should I choose for my marine engine installation?

Grade selection depends on the equipment manufacturer's specification and the classification society requirements. As a general guideline: Grade 36 (yield 250 MPa) is suitable for pump sets and light auxiliary equipment; Grade 55 (yield 380 MPa) covers generator sets and medium-duty machinery; Grade 105 (yield 725 MPa) is specified for main propulsion engines and high-load applications. ASTM A193 B7 (tensile min. 860 MPa) is required for high-temperature areas such as exhaust systems and steam lines.

Can sinofastener arrange third-party inspection for foundation bolts?

Yes. Our foundation bolts are manufactured to meet the material and mechanical requirements of ABS, DNV, LR, and CCS classification society rules. EN 10204 3.1 material certificates are provided as standard. For projects requiring independent verification, we can coordinate third-party surveyor inspections (e.g., DNV or ABS surveyor witness of tensile testing and dimensional inspection) upon request.

What surface treatment is suitable for engine room foundation bolts?

For typical engine room environments, hot-dip galvanizing (HDG) per ISO 1461 is the standard choice, providing zinc coating for corrosion protection. Per ISO 1461 Table 1, minimum coating thickness varies by bolt diameter and material thickness. For areas with higher corrosion risk (bilge area, seawater exposure), Dacromet coating or A4-80 (316) stainless steel offers enhanced resistance.