Martin F9SK Martin-Flex Coupling Flange Assembly.
Martin F9SK Martin-Flex Coupling Flange Assembly is a component of Martin’s Martin-Flex disc-style flexible coupling line.
| Bore Dia. [Min] | 1/2 in |
| Coupling Size | 9 |
| Bushing Series | SK |
| Bushing Type | QD |
| Required per Coupling | 2 |
| RPM [Max] | 2800 rpm |
| Input Bore Range | 1/2 to 2 5/8″ |
| Torque Rating [Max] | 4349 in lb |
| Bore Dia. [Max] | 2 5/8 in |
| Outside Dia. | 9.25 in |
| Style | Bushed From Hub Side |
| Weight | 8.6 LB |
| EAN or UPC | 697950081601 |
Martin-Flex is Martin’s disc-style flexible flange coupling — two hubs, each bolted to a flanged disc pack, connect the driving and driven shafts. The disc pack flexes slightly to absorb misalignment and shock without the wear-prone elastomeric insert a jaw or Quadraflex coupling relies on, trading a moderate amount of extra cost for a design with fewer parts that wear out in normal service.
Confirm bore size and keyway on both hubs, and check the flange size and bolt pattern against your existing hardware if you’re replacing only the flange assembly rather than the complete coupling. Check the torque rating against your application’s peak load and note the maximum allowable misalignment before installing — as with other flexible couplings, it’s not meant to correct a poorly aligned shaft, only to tolerate a small amount of normal operating misalignment.
Martin-Flex couplings are used in general industrial power transmission where a maintenance-free flexible connection is preferred over a lubricated design like a grid or chain coupling — pumps, fans, compressors, and similar equipment running at moderate torque and speed.
This is the F9SK size Martin-Flex component — confirm the flange bolt pattern and bore against your existing hardware before ordering, since sizes aren’t visually interchangeable at a glance.
