Lug and Leaf Type Air Shaft Technical Information
What is an Air Shaft?
Air Shafts are used in the manufacturing processes for fitting into a core onto which materials such as paper, card and plastic film are wound. An Air Shaft is designed so that, on fitting into a core, it can be readily expanded, thereby achieving a quick and firm attachment, it may also be easily deflated to facilitate easy withdrawal of the shaft after winding of product is complete. Their efficient design makes them ideal for mounting onto bearing housings to enable the winding or unwinding of rolls of stock material with the minimum of equipment down time. The advantage of using an Air Shaft is its ability to grip the core, without damage, whilst providing a positive interface to control the web via motors & brakes. Air Shafts are available as either Lug Type (with bladder down the centre) or Strip Type (bladders on the periphery of the shaft)
Lug Type Air Shafts
Lug type Air Shafts are the most popular and versatile of the types of Air Shafts. They are available in sizes ranging from 1.5"mm to 6", manufactured in Aluminium, Steel and Carbon Fibre where applicable. Shafts are bespoke and manufactured to the customer’s requirements to suit new or existing machinery. They are economical to repair and maintain, with a wide range of spares held on-site for immediate despatch.
Air Shaft Applications
Applications for Air Shafts generally fall into the following uses:-
Continuous Core |
Cantilever Air Shaft |
Multi-Slit Air Shaft |
For standard unwinding & rewinding applications. Lugs are spread apart, symmetrically along the length of the Air Shaft body | Ideal for Narrow slitting or single cores. Makes handling of reels easier on changeover. | Overlapping/meeting lugs are used to supply continuous gripping for multi-slitting applications |
Duplex Slitting | ||
A pair of shafts employed in tandem winding reel alternatively. Load on shafts are reduced by 50%, eliminating interleaving |
Construction of Lug shaft| key type air shaft
A Lug type Air Shaft can be best explained as metal tube with slots cut out of it with a sealed rubber tube inside which expands to push out Rubber or metal lugs which grip the core. The journals are fitted in each end of the tube to suit the machine dimensions. The diagram below shows the general parts used in a Lugshaft:-
This Leaf shaft can also used for coreless applications where there is a requirement to wind the material directly on to the shaft. The standard leaf shaft design is modified to incorporate a bar along the length of the shaft to trap the web.