The Ultimate Guide To Screw Head Locator Pins

screw head locator pin

Locating pins, also known as workholding bolts or headed dowels, are used to position workpieces onto a fixture. They are used in semi-to-fully automated manufacturing to quickly and accurately position workpieces before processing. Locating pins are used in combination with hardened locating bushes to enable exact, low-wear, and fast changes of the workpiece. They come in a range of shapes, including flat, tapered, round tapered, taper radius, spherical, ball end, and bullet nose.

Characteristics Values
Use Locating and positioning workpieces onto a fixture
Industry Semi-to-fully automated manufacturing
Examples Automotive welding assembly lines, sheet metal stamping die presses, scanning and labeling packaging machines, and semiconductor pick-and-place assembly
Design features One uniquely shaped end machined to a precision tolerance, referred to as the 'head', and mounting features machined into the other end, referred to as the 'shank', and an optional shoulder in the middle
Head-style shapes Flat, Tapered, Round Tapered, Taper Radius, Spherical, Ball End, Bullet Nose
Shank style Straight (Press-fit), Threaded, Tapped
Material Steel, Stainless Steel, Tool Steel, Bearing Steel

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Locating pins with ball-end Form A

The ball-end form minimises the tendency to jam, which can be caused by the locating hole not being at right angles to the pin or by the pushing force not being parallel to the pin axis. This is achieved by the inclined setup of the join part, which keeps the clamping inclination to a minimum.

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Locating pins with internal thread

There are two styles of locating pins with internal threads: style B, which is a cylindrical pin, and style C, which is a rhomboid pin. Versions D1 = 5 and D1 = 6 do not have an internal thread.

Locating pins are used for fine tolerance positioning of a workpiece. They can be used by themselves or in combination with a bushing or pin holder. They are often used in semi-to-fully automated manufacturing, where workpieces must be positioned quickly and accurately before processing.

For example, to constrain a workpiece's degrees of freedom for a simple drop-down fixture, designers can combine a round head pin with a diamond head pin. The round head pin will constrain the workpiece in all directions, while the diamond head pin offers additional clearance in two directions to reduce the risk of binding.

Other styles of locating pins include tapered, tapered radius, spherical, bullet nose, and triangle-shaped.

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Locating pins with screw mount hole

The screw mount shape allows for a bolt to secure the locating pin in place from the top face, providing stability and eliminating the need for tapped screws. This feature makes them ideal for use in areas where tapped screws cannot be utilised.

The pins are available in various materials, including steel, stainless steel, and hardened steel, each offering unique advantages depending on the application requirements. For instance, stainless steel pins provide corrosion resistance, while hardened steel pins offer increased durability.

When installing locating pins with screw mount holes, it is crucial to align the pin with the hole or bushing and gently insert it until it is secure. Ensuring a snug fit is essential, as excessive protrusion can affect performance. Additionally, adhering to the manufacturer's guidelines and specifications will help achieve optimal results.

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Socket pin-in-hex flat head cap screw

These screws are known for their chemical resistance and heat resistance, making them easy to remove during maintenance. They can also be treated with anti-loosening solutions in advance.

In addition to the standard version, there are also undercut and countersunk head variations available.

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Locating pins with flattened ball-end

The flattened ball-end design minimises the tendency to jam, which can be caused by the locating hole not being at right angles to the pin or by the pushing force not being parallel to the pin axis. This is achieved by the inclined setup of the join part.

Locating pins are used for fine tolerance positioning of a workpiece. They can be used by themselves or in combination with a bushing or pin holder.

There are several other types of locating pins, including:

  • Flat-head pins: used for radially locating parts, but not recommended for drop-down vertical locating.
  • Tapered pins: the large flat taper on the head reduces the risk of binding and corrects slight axial misalignment during vertical drop-down and removal actions.
  • Round tapered pins: these reduce the risk of damage to the pin and workpiece by rounding out sharp angles. They also correct slight axial misalignment.
  • Taper radius pins: these further reduce the risk of binding and correct axial misalignment by extending the flat taper to a rounded point.
  • Spherical pins: these reduce the risk of binding and damage to the pin and workpiece by rounding out the top of the pin.
  • Bullet nose pins: these are good at correcting axial misalignment by using a long radiused taper with a rounded point. They also help to prevent binding and facilitate the insertion and removal of workpieces.

Frequently asked questions

Locating pins, also known as workholding bolts or headed dowels, are specialised fasteners used for locating and positioning workpieces onto a fixture. They are used in semi-to-fully automated manufacturing where workpieces must be positioned quickly and accurately before processing.

Screw head locator pins are used for fine tolerance positioning of a workpiece. They can be used by themselves or in combination with a bushing or pin holder.

There are several types of screw head locator pins, including:

- Large head locating pin

- Small head locating pin

- Shoulder locating pin

- Flanged locating pin

- Tapered, flanged, spring-loaded locating pin

- Straight locating pin

Screw head locator pins offer several benefits, including:

- Quick and accurate positioning of workpieces

- Reduced risk of binding

- Correction of axial misalignment

- Reduced damage to the pin and workpiece

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