Forks with ISO suspension

Product features ISO forks

ISO forks
ISO forks
  • Current standard for the suspension for forks
  • Suspension is made by fork hooks slided onto the fork carrier
  • Characteristic is a 20° bevelling at the fork hook / profile of fork carrier
  • With OptimaForkHeel for up to triple operating life
  • Produced out of VETTER special fork steel

Norms ISO forks

  • Connection measures according to ISO 2328
  • Production according to ISO 2330:
    • Minimum triple static load without permanent deformation
    • Minimum 1,000,000 stress cylcles with 25 % overload

Connection measures ISO suspension

Today, the ISO suspension is world-wide the most common way of connecting forks to the lift-truck.

According to the rated truck capacity the ISO standard consists of 5 classes, each of them having a form "A" and "B" (e.g. class "2A" or "2B"). The difference in the forms "A" and "B" ist the fork drop (clearance lower hook to floor).

All measures are defined in the international standard ISO 2328. In the table below, the most important measures are listed.

Connection measures ISO 2328
Class Capacity (kg) LC (mm) Drop a = mm b (mm) c1 (mm) c2 (mm) h1 (mm) h2 (mm) k1 min. (mm) k2 (mm) m1 max. (mm) RH (mm)
ISO 1A 0 - 999 400 + 600 a) 76 331 16,5 16 394 306 14 13 31 475
ISO 1B 0 - 999 400 + 600 a) 114 331 16,5 16 432 306 14 13 31 510
ISO 2A 1.000 - 2.500 500 + 600 b) 76 407 16,5 16 470 382 14 13 31 550
ISO 2B 1.000 - 2.500 500 + 600 b) 152 407 16,5 16 546 382 14 13 31 625
ISO 3A 2.501 - 4.999 500 + 600 76 508 22 21,5 568 477 17 16 40 655
ISO 3B 2.501 - 4.999 500 + 600 203 508 22 21,5 695 477 17 16 40 780
ISO 4A 5.000 - 10.000 600 127 635 26 25,5 743 598 20 19 47 845
ISO 4B 5.000 - 10.000 600 254 635 26 25,5 870 598 20 19 47 970
ISO 5A 8.001 - 10.999 600 127 728 35 34 830 680 26 25 65 930
ISO 5B 8.001 - 10.999 600 257 728 35 34 960 680 26 25 65 1060

Note:

ISO 1 + 2:  Tolerance + 1 mm
ISO 3, 4, + 5: Tolerance + 1,5 mm

ISO 5 is introduced in 2003 and still unusual in Europe. The capacity range of 5,000 - 10,000 kg is still mainly covered by ISO 4.

a) 600 mm is used in the USA
b) 600 mm is used in the USA, Asia, Australia