Elevator Bolts

Product Category

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Bolt Type

Carriage bolts, or carriage screws, have a square neck that keeps them from turning once tightened. These bolts have domed heads. Use in square holes for wood-to-wood and wood-to-metal fastening.

Elevator bolts are similar to carriage bolts, except they have a flat head, which gives them low head clearance. Their square neck keeps them from turning once tightened.

Eyebolts have a looped head that can be forged with or without weld seams, closed or unclosed, and may have a shoulder to better support angled lifting. They are used for lifting, attachment, and for tie-downs.

Flange bolts have a flange under the head which distributes the clamping load over a greater area.

Hex bolts are hexagonal-shaped and feature a chamfered, or grooved, point to aid insertion into a tapped hole or nut.

Lag bolts are similar to wood screws; they have threads designed to bite into the surface and resist pull-out. Lag bolts are larger than wood screws and are usually used to hold two pieces of wood together.

T-slot bolts have heads designed to fit into machine table slots; these bolts won’t twist or jam and provide a larger bearing surface.

Toggle bolts have winged supports to anchor a bolt to a wall stud or ceiling joist. To insert, fold the toggle wings flush with the bolt, and push the bolt through a drilled opening until the wings pop open on the other side.

Fasteners
- Bolts
  - Elevator Bolts

Bolt Head Style

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Head Style

Button head bolts are similar to standard pan heads but have a curved top.

Fillister head bolts have a thick cylindrical head with a deep drive slot for higher levels of torque. The head is smaller than a round head.

Flange hex head bolts have an extra bearing surface between the top of the bolt head and the body that provides an additional gripping strength. This flange area resembles a flat washer, with its semi-flat disc shape.

Flat head bolts are designed to fit flush to the surface when used with countersunk holes.

Hex head bolts are hexagonal shaped with a flat bearing surface.

Large diameter round head (elevator) bolts are thin and flat, giving the bolt low head clearance.

Oval head bolts are tapered on the bottom like flat heads to fit flush in countersunk holes, but they have an oval top.

Round head bolts have a dome shape. They are considered an older style and are commonly replaced by other heads.

Socket cap bolts, also known as Allen head bolts, have a recessed drive, and are commonly used when there is not enough clearance for a conventional wrench or socket. They are fastened with an Allen wrench, which is also called a hex wrench or hex key.

Square head bolts have a square shaped, prominent head that is easy to access with a wrench or by hand, when more torque is needed.

Truss head bolts have an extra-wide lower-profile dome with a slightly rounded top.

Bolt Drive Style

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Bolt Drive Style

Combination Phillips-slotted drives are used with either a Phillips or standard slotted driver. The drive style is designed so that the driver will cam out, or slip out, under pressure to prevent over-tightening. These are often used to attach knobs to furniture.

External hex drives are six-sided, or hexagonal, and are driven by a crescent wrench, combination wrench, or sockets. They require minimal clearance above the fastener because they can be tightened or loosened from the side. External hex drives outperform external square drives in scenarios with limited fastener access, because smaller swing arcs may be used to rotate the fastener.

Internal hex drives, also known as hex-socket drives, are similar to hex drives, but have a hexagonal hole in the center that requires an Allen key, also known as a hex key or Allen wrench.

Not applicable defines a fastener that is either hand-driven, or held in place during use. Hand driven examples include knurled screws and spade screws. Since these are head styles, the drive style is not applicable. Carriage bolts, eye bolts, J bolts, and U bolts are all held in place during use while the nut is fed onto the threaded end of the fastener, tightening the bolt in place from the end rather than the head. The carriage bolt is held by its square neck, while eye, J, and U bolts are held in place by hand or with a tool.

Phillips drives have x-shaped slots with rounded corners and are driven with a Phillips screwdriver. The slot is designed so that the driver will cam-out, or slip out, under pressure to prevent over-tightening.

Slotted drives have a linear slot and are used with a flat-bladed screwdriver. These drives are commonly used in woodworking and are prone to slippage.

Spline drives have twelve splines, or rounded plateau-like ridges, on the fastener and tool. Spline drives resist cam out, so they are frequently used in high-torque applications, such as tamper-proof lug nuts.

Star drives, also called Torx drives, have 6-pointed indentations that provide more driving surface area. These drives resist cam-out better than Phillips drives or slotted drives. They are used with a Torx screwdriver.

Triple square drives, also known as XZN, drives have 12 equally spaced tips, each with an internal 90 degree angle. Three identical overlaid squares are rotated to form a pattern. Triple square drives are useful in higher torque applications, such as drive train components. Many German vehicle manufacturers use triple square fasteners on their automobiles.