CAGE NUT (BN 3307)

CAGE NUT (BN 3307)
A cage nut or caged nut (also called a captive or clip nut) consists of a square nut in a spring steel cage which wraps around the nut.

The cage has two wings that when compressed allow the cage to be inserted into the square holes, for example, in the mounting rails of equipment racks. When the wings are released, they hold the nut in position behind the hole.

This design requires insertion tools to install the cage nut into the hole.

Newer designs featuring a squeeze-and-release tab allow for tool-less installation.
The square-hole cage nut can be used wherever a square hole can be punched.

Using cage nuts provides several benefits over threaded holes.
  • It permits a range of choice of nut and bolts size (e.g. metric vs imperial) in the field, long after the equipment has been manufactured.
  • If a screw is over-tightened, the nut can be replaced, unlike a pre-threaded hole, where a hole with stripped threads becomes unusable.
  • Cage nuts are easy to use on materials too thin or soft to be threaded.The nut is usually slightly loose in the cage to allow for minor adjustments in alignment. This reduces the likelihood that the threads will be stripped during equipment installation and removal. The dimensions of the spring steel clip determines thickness of the panel to which the nut may be clipped. In the case of square-hole cage nuts, the clip dimensions determine the range of hole sizes to which the clip will securely hold the nut. In the case of slide-on cage nuts, the clip dimensions determine the distance from the panel edge to the hole.

INTERNATIONAL STANDARDS

STANDARDS:
  • BN 3307
  • BN 80350
  • C 4800 SERIES

APPLICATIONS

A common use for cage nuts is to mount equipment in square-holed 19-inch racks (the most common type), with 0.375 inches (9.5 mm) square-hole size.

There are four common sizes:
  • UNF 10–32 and, to a lesser extent, UNC 12–24 are generally used in the United States;
  • M5 (5 mm outside diameter and 0.8 mm pitch) for light and medium equipment
  • M6 for heavier equipment, such as servers.
Although some modern rack-mount equipment has bolt-free mounting compatible with square-hole racks, many rack-mount components are generally mounted with cage nuts.

MATERIAL

 

Material Available:

  • LOW CARBON STEEL : C1006 - C1045
  • STAINLESS STEEL: SUS304, SUS316, SUS410
  • GRADE 8.8: C1018 - C1022, 10B21
  • MILD STEEL / MID CARBON STEEL: C1035 - C1045
  • ALLOY STEEL: SCM435 - SCM440 (Grade 10.9, Grade 12.9)
  •  │8│GRADE 1008K 1010 
  • 7 8 GRADE 1015(M<16) CH38F (M≥16)
  • 8 10 GRADE CH38F 1039 10B21 10B33
  • 9 12 GRADE 1039 10B21 10B33 10B38 
  • BRASS C2600, C2700, C2680
  • RED BRASS C1100
  • Phosphor Bronze C5191
  • Aluminum Alloy 1050, 5052, 6061
  • Material according to customer’s specifications

SIZE RANGE

STANDARD SIZES:
  • M3 - M12
  • 3/16 - 3/8
  • 8# , 10#, 12#

SURFACE TREATMENT

SURFACE TREATMENT TYPES:

  • HEAT TREATMENT
  • ZINC PLATED – WHITE ZINC / YELLOW ZINC / BLACK ZINC
  • Zinc trivalent coatings Cr3+ (Meet RoHS standards)
  • Zinc hexavalent zinc plating Cr6+
  • Nickel plating
  • Black Oxide
  • Hot Dip Galvanised
  • GEOMET® 500
  • DACROMET®
  • Passivation
  • All electro-plating, electro-coating and surface treatment specifications can meet customer's requirements.