PFB | PRB Thread locking with jamming action Polyamide patch coating/ Polyamide complete coating

The torque values are based on a test of a thread without preload with a nut thread 6H at room temperature. For PFB and thread lenghts l0 < l2, l2 is reduced in such a way that one to two thread turns are not coated at the end of the thread.

Description
The polyamide patch coating PFB is a process whereby an elastic plastic material (Polyamide) is applied to a part of thread which creates a jamming action during the tightening of a nut. The coating can be produced either as a patch or complete coating. The axial play between the bolts and nut thread is taken up by the polyamide thus ensuring maximum surface pressure between the opposite uncoated thread flanks. This process counteracts the loosening and unscrewing on their own. There is no cure time required, the thread contact is instantaneous resilient. The typical spray edge zone of the polyamide deposit prevents shear blasting.

Features
– High thread locking action, shakeproof. Excellent convenient for adjusting bolts.
– The locking system is a captive component of the standard part, which eliminates the fitting of additional belay.
– Temperature resistant from – 60 °C up to 120 °C
– Approval for food areas
– High chemical stability
– Use is also possible, for instance, in oil-contaminated threaded holes
– Multi use is possible whereby the jamming effect after the 5th removal is around 50 % of its original strength.

Information
Polyamide patch coating is offered for GN 615.3 (see page 840) spring plungers. A blue coating indicates type K or KN, green indicates type KS or KSN (high spring load). Polyamide complete coating is available for GN 252 and GN 252.5 blanking plugs (see page 1685) as a type.