Understanding the different parts of a boat is essential for anyone involved in marine design, construction, or maintenance. From the bow and stern to the hatches and propulsion systems, every component plays a role in performance, safety, and reliability. Together, these parts create a system built to handle the demanding conditions of the sea.
In marine engineering, reliability depends on precision. Springs, pressings, and anti-vibration mounts are used throughout vessels to control movement, manage load, and enhance comfort. From gas springs in hatches to torsion springs in cabin hinges, these components make operation smoother and more secure.
In this guide, we’ll explore the main boat components and their functions, highlight how Lesjöfors’ spring technology supports marine applications, and share real-world examples of our products in action with leading boatbuilders and rescue organizations.
Parts of a boat: boat components
Hull and exterior structure
The hull and exterior structure form the foundation of a vessel, shaping stability, buoyancy, and strength.
1. Hull
The hull is the body of the boat, which determines how the vessel moves through water and withstands external forces. Hull types vary from displacement and planing to semi-displacement, and each is suited to different speeds and sea conditions. Common construction materials include steel, aluminum, and fiberglass.
2. Bow
The bow is the front section of the boat, designed to cut through waves and reduce drag. Its shape influences performance and handling, especially in rough seas.
3. Stern
Located at the rear, the stern of a boat supports the propulsion and steering systems. It must absorb vibration and load from the engine and propeller. Anti-vibration mounts and compression springs in this area help minimize mechanical wear and noise.
4. Keel
Running along the underside of the hull, the keel provides structural strength and balance. In sailing vessels, it also stabilizes the boat against wind forces.
5. Beam
The beam is the boat’s widest point, affecting both stability and space. A wider beam improves steadiness, while a narrower one enhances speed and maneuverability.
6. Deck
The deck is the upper floor of the boat, supporting fittings such as cleats, winches, and hatches. Gas springs are often installed in deck lockers and panels to control lifting and prevent slamming.
7. Gunwale
The gunwale is the reinforced upper edge of the boat’s hull. It adds rigidity and provides mounting points for handrails, fenders, or safety lines.
Openings and access points
Access points such as hatches and companionways provide entry while remaining watertight and secure. Marine-grade springs, hinges, and locks are essential to their performance.
8. Hatch
A hatch gives access to storage areas, cabins, or engine rooms. Built to handle constant movement and exposure, hatches must seal tightly and open smoothly.
Parts of a boat hatch
A standard hatch includes a frame, lid, hinges, locks, and a seal. Stainless steel or anodized aluminum frames resist corrosion, while durable seals keep water out.
Gas springs used in hatches
Gas springs counterbalance the weight of hatch lids, ensuring a controlled open/close motion and preventing sudden drops. Lesjöfors manufactures marine-grade gas springs from corrosion-resistant stainless steel, with customizable pressure, fittings, and locking features.
9. Porthole
A porthole allows light and air into the interior while maintaining watertight integrity. Compression gas springs are used in latches to ensure safe operation, providing controlled lifting and secure closure under pressure. This not only prevents accidental slamming or overextension but also enhances the reliability of the seal in demanding conditions.
10. Companionway
The companionway connects the deck and cabin. Smooth operation is key to safety and comfort. Compression gas springs and hinge systems from Lesjöfors support companionway hatches to operate reliably in all sea conditions.
Propulsion and navigation
Propulsion and steering systems convert energy into movement and direction. Springs and anti-vibration mounts ensure precision and reduce wear in these mechanical systems.
11. Engine
The engine powers the vessel through the water. Marine engines are designed for torque, efficiency, and endurance.
Marine engine components and springs
Compression and tension springs are used in valves, injectors, and throttle systems. Anti-vibration mounts protect the hull and reduce noise, improving comfort and extending component life.
12. Propeller
The propeller transfers power from the engine into thrust. Shock-absorbing springs and bushings inside the hub help protect the drivetrain from load spikes.
13. Rudder
The rudder steers the vessel by redirecting water flow. It’s built to handle constant pressure and movement.
Tension springs in propellers and rudders
Tension springs in steering systems maintain consistent feedback and help the rudder return to center. Lesjöfors tension springs are engineered for high-cycle performance and corrosion resistance.
14. Tiller or wheel
The tiller or wheel controls the rudder. Springs are often used in linkage assemblies for smooth, responsive steering.
15. Mast and boom
On sailing boats, the mast and boom hold the sails and rigging. Springs and locking components allow controlled tensioning and easy adjustment under load.
16. Sails
Sails harness wind power. Spring mechanisms in furling systems, cleats, and winches maintain line tension and control sail deployment.
Interior and compartments
Below deck, springs and metal fittings ensure safe, controlled movement in confined spaces. These boat components combine durability with comfort.
17. Cabin
The cabin is the enclosed living or working area. Hinges, locks, and springs help fixtures move safely despite vibration and motion.
Torsion springs in cabin hinges
Torsion springs provide balanced rotation in doors, tables, and seating systems, preventing sudden movement.
18. Berth
A berth is a sleeping area. Folding bunks often use gas springs for controlled adjustment.
19. Galley
The galley, or onboard kitchen, requires secure fittings. Gas springs in drawers and cabinet latches prevent accidental opening, and ensure safety whilst cooking.
20. Head (bathroom)
Marine bathrooms use compact components resistant to moisture and movement. Spring-loaded valves and latches ensure reliable operation.
21. Salon
The salon is the main living space, featuring tables, seating, and storage.
Extension springs in cabinets
Extension springs in cabinet doors and lids control opening force, reducing wear and preventing unintended movement.
How boat components impact applications
Every part of a boat contributes to its strength, comfort, and functionality. Quality components reduce vibration, improve handling, and extend service life. Lesjöfors’ precision-engineered springs and mounts help vessels perform reliably in saltwater environments, where durability and corrosion resistance are critical.
Gas spring case studies – marine applications
Lesjöfors components are trusted by leading shipbuilders and marine organizations worldwide.
Sargo’s award-winning boats
Lesjöfors has been supplying Sargo Boats with gas springs for nearly 25 years. Our products ensure the smooth operation and exceptional reliability of deck hatches, doors, and storage systems, even in freezing Nordic conditions.
Swedish Sea Rescue Society
Lesjöfors supplies stainless steel gas springs for the Swedish Sea Rescue Society’s Victoria Class vessels. Our components have proven reliable in extreme Nordic conditions and are now trusted as part of their life-saving marine fleet.
Why choose Lesjöfors for gas springs and components in the marine industry?
Lesjöfors offers one of the most comprehensive ranges of springs and pressings for marine applications, supplying everything from gas springs and hinges to anti-vibration mounts. With decades of experience and a global manufacturing network, Lesjöfors delivers dependable component solutions for shipyards, rescue services, and leisure craft manufacturers.
Marine-grade, corrosion-resistant stainless steel
Stainless steel AISI 316
When engineering components for the boat industry, Lesjöfors uses stainless steel AISI 316. This is the preferred marine-grade alloy because of its exceptional resistance to corrosion and pitting in saltwater environments. Its molybdenum content gives it superior performance compared to AISI 304, maintaining strength and integrity even after prolonged exposure to seawater and humidity. Durable, formable, and reliable, AISI 316 ensures Lesjöfors components perform safely and consistently in the toughest marine conditions.
Meet us at upcoming marine trade fairs
Lesjöfors will be attending several leading international events for shipbuilding, design, and marine technology, meeting customers and partners to discuss the latest spring and component solutions for the marine industry – we hope to see you there.
If you’d like to arrange a meeting with one of our representatives during the events to discuss our marine-grade components in more detail, get in touch with us today.
METSTRADE | Amsterdam (18–20 November 2025)
Dedicated to ship equipment, systems, and components, METSTRADE is the world’s largest marine trade exhibition.
Boot Düsseldorf | Düsseldorf (17–25 January 2026)
Europe’s leading event for yachts, marine leisure, and water sports, Boot Düsseldorf attracts the global boating community.
FAQs
The main parts of a boat include the hull, bow, stern, keel, deck, and beam, which form its structure and stability. Other important components are hatches, portholes, engines, propellers, rudders, and interior fittings, each designed to perform a specific function in propulsion, control, or access.
Boats use a range of gas, compression, tension, and torsion springs, as well as anti-vibration mounts and precision pressings. These components support hatches, doors, and storage systems, stabilize engines, and absorb vibration to improve comfort and performance on board.
Marine environments expose components to saltwater, humidity, and high mechanical stress. Corrosion-resistant materials such as stainless steel AISI 316 prevent rust and pitting, ensuring long service life and consistent performance, even under continuous exposure to harsh conditions.