Grooved pins offer flexible fastening

Edited by the Engineeringtalk editorial team Aug 29, 2008

Tappex Thread Inserts also offers an extensive range of Grooved Pins.

Tappex Grooved Pins provide extremely flexible fastening systems that enable the designer to select the precise configuration to suit a particular application.

Tappex can offer 21 standard Grooved Pins, including three headed varieties, in steel, stainless steel, aluminium and brass.

The pins give high shear strength and good wear resistance.

They are strong, reusable, resistant to shock and vibration and easy to install.

Each pin incorporates three longitudinal grooves swaged or formed into a cylinder of material, which has the effect of increasing the diameter.

In the case of the unheaded pin this may be over part or all of its length and may be tapered or parallel.

The grooves are always parallel with headed pins.

Installation of each pin causes the grooves to compress, which produces outward pressure on the walls of the hole and in so doing secures location of the pin.

As resistance to withdrawal occurs wherever the grooved diameter is compressed, it can be over the whole length of the pin instead of just at one point as with traditional taper pins, plain pins, keys or locating pins.

Another major advantage with grooved pins is simple hole preparation and installation.

No reaming or threading of the hole prior to installation is required and there is no need for special and sophisticated installation equipment.

Because the pin is held in position under elastic tension it cannot easily be dislodged in harsh environments and is very resistant to shock and vibration.

When removed from the application the grooves recover their form and can be reused many times with only minimal reduction in pull out performance.

Three of the Tappex Grooved Pins - the S4, N4 and S50 demonstrate the versatility of the range.

The S4's half length reverse tapering grooves ease installation into blind drilled holes.

The half length plain portion can be used as a drive element stop pin or bearing, or as a handle on a tap replacing an expensive threaded fastener.

The headed N4 is ideal for fixing name plates, panels, linings, pipe clips or any additional component to an assembly.

It can be rapidly installed showing a cost saving over conventional screws.

The S50 has full-length parallel grooves.

A plain spigot at each end of the pin allows location in the component before assembly and removes any problem of orientation of the fastener.

According to Tappex's Marketing Manager, Peter Rush: "We encourage designers to take full advantage of the extensive technical advisory service provided by our team of applications engineers".

"The grooved pin is a good example of a solution looking for a problem".

"The number of applications is legion and very varied across many industries".

"As well as our standard range, we also have the facility to vary our pins to incorporate different groove lengths or special features if the nearest standard part does not meet requirements".

"One example which demonstrates this is a customer who was already using our pins for several mechanical applications in their range of precision electronic measuring equipment".

"They needed to reduce the effect of electromagnetic interference, which required good electrical conductivity between the various metal components".

"Using a standard pin with gold plating applied proved to give them a solution when pressed into adjacent metal components".

A comprehensive 32-page A4 brochure provides a detailed description of the Tappex Grooved Pins including typical applications and hints for designers.