HSK Collet Adaptors



  • Conforming to DIN 69893
  • Manufactured from Case hardening steel
  • Duly tempered and hardened to 58±2 HRC
  • Available in forms A,B,C,E,F
  • Balancing:
    • Standard G6.3@20000 RPM
    • G2.5@25000 RPM on request
  • Dual contact provides higher radial and axial stiffness and accuracy
  • Suitable for high speed applications
HSK Collet Adaptors
HSK Collet Adaptors

G6.3@20000RPM

58±2º

Case Hardening Steel

DIN 69893

0.005 mm


Collet adaptor

Collet adaptors transfer the machine spindle's motion to the cutting tool. The tapered body of the adaptor attaches to the spindle by means of a pull stud and thus rotates along the spindle. The cutting tool is held by the collet which is further mounted onto the adaptor by means of the collet nut. The collet adaptor is capable of accomodating a wide range of collets thus allowing the use of a single adaptor across a number of tool sizes.

What is a Hollow Shank Adaptor?

HSK or Hollow Shank Adaptors have a short shank and a shallow taper of 1 : 10 as compared to 7 : 24 ratio of a BT adaptor. The HSK holders were designed to facilitate high speed machining without compromising the quality.

The machine spindle envelopes the taper shank of the adaptor while the drawbar along with the collet sleeve is pushed inside the hollow shank. As the drawbar retracts, the collet fingers are pushed against the inner surface of the adaptor thus engaging it with the drawbar. 

Advantages of HSK adaptors over Steep taper adaptors

The steep tapers are mounted onto machine spindles with the help of retention knobs or pull studs. The collet fingers wrap around these retention knobs screwed into the adaptors. As the spindle's speed increase the centrifugal forces acting on the spindle and the collet causes them to expand. The shank of the adaptor being stiff expands at a lower rate. The constant pull from the drawbar causes the adaptor to sink deeper into the spindle, causing a shift along the Z axis and hampering accuracy of the part.

In case of HSK adaptors however the expansion of the collet causes the fingers to further push into the adaptor thus increasing the clamping forces.The thin and flexible walls of the adaptors are subjected to thermal expansion at higher rates than the spindle leading to a firm contact between the two. Furthermore the flange contact of the adaptor with the machine's spindle prohibits any axial movement thus maintaing accuracy even at high RPMs.

Akros HSK Adaptors come pre-balanced at G6.3@20000RPM, fine balacing of G2.5@25000RPM is available on request.

Types of HSK tool holders

FORM A

  • Standard Type for machining centers and milling machines.
  • Facilitates Automatic Tool Changing (ATC)
  • Coolant is supplied through the centre
  • Drive Keys at the end of the HSK taper
  • Side holes for manual tool change (can be used as form C)

FORM B

  • For machining centers, milling and turning machines.
  • Facilitates Automatic Tool Changing (ATC)
  • Larger flange provides higher rigidity
  • Coolant is supplied through the flange
  • Drive Keys at the flange

 

FORM C

  • For transfer lines, SPMS and modular tooling
  • Manual Tool Change
  • Coolant is supplied through the centre
  • Drive Keys at the end of the HSK taper

FORM D

  • For SPMS
  • Manual Tool Change
  • Larger flange provides higher rigidity
  • Coolant is supplied through the flange
  • Drive Keys at the flange

 

FORM E

  • For high speed applications
  • Facilitates Automatic Tool Changing (ATC)
  • Coolant is supplied through the centre
  • Drive keys are removed to provide higher symmetry

FORM F

  • For high speed applications
  • Facilitates Automatic Tool Changing (ATC)
  • Coolant is supplied through the centre
  • Larger flange for provides higher rigidity
  • Drive keys are removed to provide higher symmetry

 

C.no DESCRIPTION Collet Type action
Shank

L

CA-ER-HA50L80 A50 80 ER-16,20,25,32
CA-ER-HA63L80 A63 80 ER-16,20,25,32
CA-ER-HA63L100 A63 100 ER-40
CA-ER-HA63L160 A63 160 ER-16,20,25,32,40
CA-ER-HA100L100 A100 100 ER-16,20,25,32,40
CA-ER-HA100L120 A100 120 ER-50
CA-ER-HA100L160 A100 160 ER-16,20,25,32,40