Общий каталог Yamawa 2022 - 2023 - страница 1230

Selecting different tap holder combinations by machine feed system 23. Selecting different tap holder combinations by machine feed system

The function of machine feed systems

Fully synchronous feed (Rigid) tapping system

Spindle revolution and machine feed are synchronized, a perfect thread lead and feed per revolution are realized.

Feed by lead screws A better-feed condition is realized because the tap is fed by a master lead screw shaft that has the same thread lead as this tap.

Feed by gear

The tap is fed at the same thread lead by a combinations of gears. This creates a better-feed to thread lead condition.

Characteristics of tap self-guiding behavior

Holders aspects

r=tap’s radius, s=thread relief, t=margin width Eccentric thread relief (no width of margin)

Compression Tension Spring direction

Completely rigid holder type Tap characteristics ; high cutting performance and machin- The tap is held with no axial or radial ing performance, with little to no self-guiding features. adjustment in the collet and holder. Operation ; A fully synchronous machining system with fixed rigid holder is needed. Example : "High speed tapping" and "fully synchronous tapping."

Con-eccentric thread relief (margin and thread relief)

Asynchronous feed system Best used when the spindle rotation and the machine feed are set independently, especially, if the machine feed value cannot be accurately predicted to be that of the tap thread lead.

Hydraulic or Pneumatic pressure feed system

Feed is controlled by a pressure regulation system which normally results in an inaccurate feed per revolution compared to the tap thread lead.

Adjustable spring floating holder (Tension & Compression) Tap ; High level of self-guidance due to suitable tap diameter margin and thread relief. The combination of nice portion of Machine feed and tap's thread lead margin and chamfer relief helps to make appropriate tap guidance. errors are corrected by two types of spring system in the holder, the axial tension direction of the tap and the Concentric (No relief) axial compression direction of the tap.

Manual feed Feed is controlled by operator which is difficult to keep a stable amount of feed per revolution. Technical Inf

Tap ; A full thread land stays in contact with the thread major diameter at all times. Tap has no thread relief on major diameter, creating a high level of self-guidance even with unbalanced feeding conditions.