Flange nut
Encyclopedia
A flange nut has a wide flange
Flange
A flange is an external or internal ridge, or rim , for strength, as the flange of an iron beam such as an I-beam or a T-beam; or for attachment to another object, as the flange on the end of a pipe, steam cylinder, etc., or on the lens mount of a camera; or for a flange of a rail car or tram wheel...

 at one end that acts as an integrated, non-spinning washer. This serves to distribute the pressure of the nut over the part being secured, reducing the chance of damage to the part and making it less likely to loosen as a result of an uneven fastening surface.
MATERIAL USED:
These nuts are mostly hexagonal in shape and are made up of hardened steel and coated with zinc.

The flange may be serrated to provide a locking action
Locknut
A locknut, also known as a lock nut, locking nut, prevailing torque nut, stiff nut or elastic stop nut, is a nut that resists loosening under vibrations and torque. Elastic stop nuts and prevailing torque nuts are of the particular type where some portion of the nut deforms elastically to provide a...

. The serrations are angled such that they keep the nut from rotating in the direction that would loosen the nut. Because of the serrations they cannot be used with a washer or on surfaces that cannot be scratched.The serrations help in avoiding vibration of nut and increase the holding power of nut.

The flange nuts are sometimes provided with a swivel flange which helps in creating a more stable structure without affecting finished product like a serrated flange nut.Swivel flange nuts are mostly used in joining wood and plastic.
Sometimes both faces of the nut are serrated, permitting either side to lock.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK