Washer Head Bolts
A washer head bolt is a forged fastener that combines a square head and an integrated washer into a single piece. Rather than pairing a standard headed bolt with a separate washer, the washer is forged directly under the head, creating one continuous unit with a broad, flat bearing surface. This design increases the load-bearing footprint against the mating material and eliminates the need to source, stock, and install a separate washer. Washer head bolts are typically produced with a semi-cone point on the threaded end to make installation faster and easier.
Applications
Washer head bolts are used primarily in the pole line industry, where they secure crossarms and other pole line hardware. The integrated washer provides increased bearing surface against the crossarm, distributing load more evenly and reducing the risk of the head pulling through or crushing the wood. They are commonly paired with square nuts and are typically hot-dip galvanized to resist corrosion in the outdoor, exposed environments common to overhead power and utility construction. Because pole line fasteners require longer thread lengths than standard bolts, washer head bolts are supplied with these extended thread lengths to accommodate a range of assembly thicknesses.
Manufacturing
Portland Bolt manufactures washer head bolts from 1/2″ diameter through 7/8″ diameter. These bolts are produced to ASTM A307 Grade A and are available in plain black or hot-dip galvanized finish. Each bolt is forged with a square head and a large integrated washer surface beneath the head, then threaded and finished with a semi-cone point on the threaded end. All processes, including cutting, heading, threading, and hot-dip galvanizing, are performed in-house.
Washer Head Bolt Dimensions
| Bolt Diameter | D | H | W | B | C | F | |||
|---|---|---|---|---|---|---|---|---|---|
| Body Diameter | Height (Head) | Height (Washer) | Outside Diameter (Washer) | Width Across Corners (Head) | Width Across Flats (Head) | ||||
| Max | Min | Basic | Max | Min | |||||
| 1⁄2 | 0.515 | 0.290 | 0.130 | 1.40 | 1.061 | 0.995 | 3⁄4 | 0.750 | 0.725 |
| 5⁄8 | 0.642 | 0.420 | 0.125 | 1.80 | 1.326 | 1.244 | 15⁄16 | 0.938 | 0.906 |
| 3⁄4 | 0.768 | 0.490 | 0.110 | 2.20 | 1.591 | 1.494 | 11⁄8 | 1.125 | 1.088 |
| 7⁄8 | 0.895 | 0.640 | 0.180 | 2.60 | 1.856 | 1.742 | 15⁄16 | 1.312 | 1.269 |
FAQs
A washer head bolt is a forged bolt with a square head and an integrated washer formed as a single piece directly under the head. This eliminates the need for a separate washer and provides a larger bearing surface against the mating material.
Washer head bolts are used primarily in the pole line industry to fasten crossarms and pole line hardware. The integrated washer increases bearing surface and distributes load, and the bolts are commonly used with square nuts in outdoor utility construction.
Portland Bolt manufactures washer head bolts to ASTM A307 Grade A, a common carbon steel bolt specification suitable for general and pole line applications.
Portland Bolt manufactures washer head bolts from 1/2″ diameter through 7/8″ diameter.
Washer head bolts are available in plain black or hot-dip galvanized finish. Hot-dip galvanizing is commonly specified for the outdoor, corrosion-prone environments typical of pole line construction.
The integrated washer eliminates a separate part to source, stock, and install, and it provides a consistent, forged bearing surface. This simplifies assembly and ensures the washer cannot be omitted or lost during installation.
Washer head bolts are commonly used with square nuts, which are standard hardware in pole line and utility construction.
A semi-cone point is added to the threaded end to make installation easier by helping the bolt start into the nut or hole more readily.
Yes. Washer head bolts are available hot-dip galvanized, which is commonly specified to prevent corrosion in the outdoor environments where pole line hardware is used. All galvanizing is performed in-house at Portland Bolt.