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Accreditations Northern Precision Ltd operate a quality management system in accordance with ISO 9001. The ISO 9001 standard is recognised worldwide and you can be assured of the benefits of working with a certified company knowing that our management systems are constantly assessed and improved.
Registered in England & Wales Company number 3275391
V.A.T Registration number GB 684 1384 17
Specialist Fasteners for Sheet Metal
+44 (0) 1302 836010
+44 (0) 1302 831555
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Performance & Testing Method
All performance figures are averages obtained over a range of installations and should be used as an indicator only. Panel material, hole preparation, installation tooling and method can affect part performance. We always recommend that you carry out your own tests in the actual application. Please call our sales team and we will be happy to provide you with samples as well as offering technical assistance.
Push-out (N)
Installation (kN)
Push-out (N)
Installation (kN)
Steel test panel
Aluminium test panel
Hardened bushing with sufficient wall thickness to withstand applied compression load.
Head Dia. + 1.6mm
Test panel.
Applied Load from compression gauge.
Load should be applied to the shank of the fastener only.
Compression rig base.
Push-out testing of Self-Clinching Plunger Assemblies should be performed by the gradual application of a load as shown above. Bushing height should be sufficient to allow free downward movement of the fastener during testing. The bushing bore must be centred on the body of the fastener.
Anvil Dimensions
B ±0.5
A ±0.05
Pin Dia. +2.0mm
Max. pin extension
First punch or drill the correct size hole. Do not deburr or chamfer the hole prior to installation as this will remove material required during the clinching process. It is preferable to install the fastener from the punch side of the panel.   Place the fastener in the recessed anvil with the shank facing up like in the diagram above. Locate the panel mounting hole over the shank ensuring the panel is held level.   Apply a parallel squeezing force until the body shoulder is seated against the panel with no serrations visible. Do not over squeeze the fastener into the panel as this will result in panel deformation.   When installing Self-Clinching fasteners, please pay attention to the minimum hole centreline to edge and parent material hardness limitations.
√  X
Do not remove any extra material or chamfer the hole as this could result in improper installation or reduced performance.
HRB (ROCKWELL HARDNESS B SCALE) Ensure that you are installing into a panel that is ductile and at or below the published maximum recommended hardness for the fastener.
Ensure that attention is paid to the minimum hole centreline to edge dimension for each fastener. Installing too close to an edge or bend could result in improper installation or reduced performance. Minimum centreline to edge dimensions shown for each fastener apply to one edge only. If this distance is applied on multiple sides there will be significant panel distortion unless the panel edges are supported during installation.
X  √  Min C/L to Edge Min C/L to Edge
Material & Finish
Electro Nickel plated Carbon Steel (CN) parts are suitable for installation in ductile panels with a maximum recommended hardness of 80 HRB.
Part Number Examples
Part number is made up as follows: (Type)-(Plunger code)-(Material/Finish Code) For example: NTL2-04-4-CN (Locking Plunger Assembly-1.53mm minimum sheet thickness-electro nickel plated steel) NSL2-04-4-CN (Non-Locking Plunger Assembly-1.53mm minimum sheet thickness-electro nickel plated steel)
Self-Clinching Plunger Assemblies provide a captivated spring loaded positioning pin for use in thin sheet metal components such as draw slides and consoles. When fully retracted the plunger pin sits below the underside of the panel and features a twist to lockout design (type NTL2), so the plunger pin can be locked in a fully retracted position. It can also be supplied without the lockout feature (type NSL2). Utilising a special proven clinch feature, this fastener has excellent pull-out and push-out characteristics whilst providing a flush finish on the underside of the panel. Like all self clinching fasteners they are installed using a parallel squeezing action, so require access to both sides of the panel.   Self-Clinching Plunger Assemblies are manufactured from electro nickel plated carbon steel and are suitable for installation in ductile panels with a recommended maximum hardness of 80 HRB.
Self Clinching Plunger Assembly
Type NTL2|NSL2
self-clinching plunger assembly ANVIL PUNCH ANVIL PUNCH