Air expanding shafts by AMAL-SHAFT®

AMAL-SHAFT® is the original. The shaft was invented here in Åmål in the fifties and the concept has been world leading ever since. The concept is developed continuously so we can offer you the optimal solution.
PDF: Maintenance, PDF: User instructions

You’ll find our standard collection below

Download our questionnaire for Core Shafts & Chucks.
E-mail to info@hofpartner.se

S&T – Solid or Tube section, milled grooves

Very strong
Minimal deflection
For core diameter: Ø18mm to Ø600mm
Groove widths 9, 16, 20 and 33 mm
Number of grooves varies according to application

TPPC – Thin Profile Pitch Centring

Carbon fibre reinforced aluminium profile
Light and strong
Durable
For cores: Ø70mm and Ø76mm (3”)
Groove width 20 mm

TPC – Thin Profile Centring

Ultra light weight aluminium profile
Weight optimized profile
For cores: Ø70mm and Ø76mm (3”)
Groove width 20 mm

PC – Profile Centring

Solid aluminium profile
Very cost effective
For cores: Ø70mm and Ø76mm (3”)
Groove width 20 mm

PTC 150 – Profile Tube Centring

Light weight
Available as ultra light weight (middle)
Optimized profile
For cores: Ø150mm and Ø152,4mm (6”)
Centring ledges adaptable for Ø148,5 – Ø153mm
Groove width 20 mm

Browse our air shaft and chucks broschure

AMAL-SHAFT® OPTIONS

Here is a selection of options for our expanding air axes

Multi Body

Extended Life Bearing (XLB) is standard
Easy maintenance
Active centring as option

Together with our customers we have developed a unique concept for rewinding multiple rolls on long slim expanding shafts with two or more bodies. Our concept is both robust and easy-maintenance.

This type of shaft is used mainly in plastic foil industries.
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Extended Life Bearing – XLB

Standard on Hofpartners Multi Body-applications.
Maximum production with minimum maintenance. Doubles the production and increases the life span of the bearing tenfold.

“We implemented XLB and doubled our production”

Testimony of a satisfied customer

Activated pneumatically
Inverted expansion as option (for added safety)
Sawtooth modelled expanding element in metal or rubber
Dimensions according to your wishes

Differential air shafts

Friction or differential shafts are used when winding multiple webs or rolls. They have the characteristic of taking up the differences in length that occur across the width of the web. Without a friction shaft, some of the webs will get slack which can result in rolls that have to be discarded.

The shaft rotates at a few percent higher speed and the rolls “slip” on the shaft. There are many different principles for how this works. On the simpler variants, the roller’s sleeve slips against the expander elements on the friction shaft. On the sophisticated variants, sleeves slide on the shaft itself.

We are developing a new and unique concept for frictions shafts. Our aim is to introduce it to the market in the beginning of Q2 2022.

Centring

If optimum centring of the core on the shaft is required, we can offer both passive and active centring.

Passive centring requires that you always use the same core diameter, as the shaft is adapted to this. If you desire a perfect centring regardless of the inner diameter of the sleeve, we also offer our mechanical shaft Schlumpf SF.

Active centring

Perfect centring
The expanding elements return after releasing the pressure
Expanding elements are adapted to the inner diameter of the core
Very easy to mount and demount the cores

Passive centring

The “peaks” of the body center the core
The shape of the body makes it easy to mount and demount the cores despite the tight fit
The “peaks” of the body are adapted to the inner diameter of the core

Safety valve – eliminate downtime

To eliminate expensive downtime, we have a system of separate valves for each expanding groove in the shaft. A special air nozzle is required. This nozzle has a shuttle that determines whether the roller shaft will be inflated or deflated. See picture below.
We have been delivering this system to satisfied customers for over 30 years.