


In marine construction and heavy timber framing, joining large wooden beams with steel bolts presents a unique physical challenge: wood is relatively soft. When a heavy-duty structural bolt is tightened, a standard flat washer will easily crush into the timber, permanently damaging the wood fibers and causing the structural joint to loosen and fail over time.
Dock Washers are specifically engineered to solve this "pull-through" problem. Manufactured from extra-thick steel plates with a massive outer diameter (or wide square profile), dock washers drastically expand the bearing surface. This distributes the immense clamping load safely across a large area of the timber.
Because these washers are exclusively used in outdoor, high-moisture environments—such as marine docks, coastal bulkheads, and wooden bridges—Hotop Fasteners manufactures Heavy-Duty Hot Dip Galvanized (HDG) Dock Washers. The exceptionally thick, metallurgically bonded zinc-iron alloy coating ensures that these critical load-bearing components survive decades of brutal saltwater exposure and tidal shifts without rusting.

Our dock washers are stamped from thick carbon steel plates (typically 3/16", 1/4", or even 3/8" thick). This extreme thickness prevents the washer from bending or "dishing" under the high tension of structural bolts, ensuring the timber joint remains rigid.
Waterfront environments destroy standard electro-galvanized hardware within months. Our true hot dip galvanizing process applies a heavy zinc coating (typically >50μm to 85μm) that acts as a sacrificial anode, neutralizing the corrosive effects of seawater, sea spray, and wet soil.
Stamping thick steel leaves sharp metal burrs on the edges. If these edges are simply galvanized, they create sharp "zinc spikes" that can cut dock workers or damage marine ropes. We utilize heavy mechanical tumbling to completely deburr and round the edges of our dock washers before galvanizing, ensuring a smooth, safe, and uniform coating.

| Item | Technical Specification |
|---|---|
| Product Name | HDG Dock Washers / Heavy Timber Washers |
| Material Composition | Low Carbon Steel, Medium Carbon Steel (e.g., Q235, Q345) |
| Surface Treatment | Hot Dip Galvanized (HDG) strictly per ASTM A153 / ISO 1461 |
| Available Shapes | Square, Round, or Custom Profiles |
| Bolt Size Compatibility | 1/2", 5/8", 3/4", 7/8", 1", 1-1/4" / M12 to M30 |
| Outer Dimension (OD) | Typically 2" to 4" (50mm to 100mm) or Custom Stamped |
| Thickness | 3/16", 1/4", 5/16", 3/8" (4mm to 10mm) |
| Matching Components | HDG Carriage Bolts, HDG Hex Bolts, HDG Timber Bolts |
The primary application for dock washers. They are used in conjunction with HDG carriage bolts or timber bolts to secure heavy wooden pilings, cross-bracing, and decking in coastal and freshwater marina construction.
When building wooden seawalls or bulkheads to prevent soil erosion, HDG tie rods are used to anchor the wall to the ground. A heavy square dock washer is placed on the face of the wooden retaining wall to distribute the immense tension of the tie rod across the timber, preventing the nut from pulling through the wood.
Used in the construction of large-scale wooden structures, pavilions, and pedestrian timber bridges where aesthetic, heavy-duty, and rust-free hardware is required to secure the main structural beams.
Dock washers are heavy, solid steel components. Shipping them globally requires logistics designed for extreme weight and moisture protection.

Q: Should I use a Round or Square dock washer?
A: Both shapes effectively prevent wood crushing, but they have different structural advantages. Square dock washers provide a slightly larger surface area and are traditional in heavy timber framing because their straight edges visually align with the square wooden beams. Round dock washers are often used when aesthetic appearance is prioritized or in tighter spaces where sharp square corners might protrude.
Q: Do dock washers need to be overtapped like HDG nuts?
A: No. Because a washer is a clearance hole (not internally threaded), it does not need to be tapped. However, we engineer the initial stamping punch to be slightly oversized. This ensures that even after the thick zinc layer builds up inside the hole during the hot dip galvanizing process, a structural HDG bolt will still slide through perfectly.
Q: Can you manufacture custom dock washers with offset holes?
A: Yes. If your structural engineering drawing requires a square timber washer with an off-center hole (often used to clear adjacent hardware or edge joints), our in-house stamping facility can create custom tooling to manufacture dock washers to your exact specifications.
---
Protect your marine timber structures from crushing and severe saltwater corrosion. Partner with a direct manufacturer that understands heavy-tonnage stamping and strict hot dip galvanizing standards.
Get in touch for more information, pricing, or custom requirements.