More Than a "Stopgap": Intermediate Sleeves Ensure Safe Clamping and Precision

They appear to be unimposing - but they are located at a decisive interface in the chain of the metal cutting process. Between toolholder and workpiece, the intermediate sleeves influence reliability and precision of the clamping operation. The thin-walled, mostly slotted precision sleeves cover the difference between the clamping diameter of the toolholder, and the workpiece which has to be clamped. Functioning like reduction inserts, they multiply the fields of application of the toolholders or arbors, compensate tolerances, and ensure safe and gentle clamping of gear wheels. The newest sleeve design can do even more. Intermediate sleeves with nozzle effect extend the tool service life and increase the volume machining.
 
From the technical point of view, these flexible accessories have highly sophisticated features. They evenly transfer the clamping force via their whole wall, radial to the toolholder onto the workpiece, or onto the tool shank. Thereby the complete clamping force acts on them. Eroded slots in the wall provide the necessary flexibility to the intermediate sleeve, and leave enough space for the coolant supply. Since they are an additional interface, they have a great influence on the achievable run-out and repeat accuracy. In case of intermediate sleeves for precision toolholders, it is lower than 0.003 mm.
 
Intermediate sleeves are mainly used in toolholding systems for covering the clamping diameters. Various clamping diameters can be reliably clamped in one mounting, which increases the user‘s flexibility, and in turn, saves the user money. They can be used in hydraulic expansion toolholders, but also for tool mountings with polygonal clamping technology, or in toolholders with elastomer technology. There are two considerable restrictions: due to the thermal effects, intermediate sleeves cannot be used in heat shrinking toolholders, whereby the flexibility of the mountings is significantly reduced. However in collet chucks, mechanical collets are used. They also cover various clamping diameters and thus replace the intermediate sleeves. But their run-out accuracy is not efficient for most of the precision applications, which differentiates from toolholders where intermediate sleeves are used. 

Comments

Post a Comment

Popular posts from this blog

What is Class I Division 2?

Image
A Class I Division 2 is a location: (1) In which volatile flammable gases, flammable liquid-produced vapors, or combustible liquid-produced vapors are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems or in case of abnormal operation of equipment, or (2) In which ignitable concentrations of flammable gases, flammable liquid-produced vapors, or combustible liquid-produced vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operation of the ventilating equipment. Class I Division 2 Classification Class I Division 2 refers to the ANSI/ISA 12.12.01 standard. This standard was previously UL1604 until UL recommended the newer ANSI/ISA standard be used and that all hazardous location products be certified under this standa
Read more

FUSE SIZING CONSIDERATIONS FOR HIGHER EFFICIENCY MOTORS

Image
When selecting the proper fuse for short circuit protection in motor starting applications, it is important to not only ensure that the fuse will not nuisance open during motor start up times, but also that the fuse will coordinate as required with overload relays. When sizing fuses between 125% and 150% of the motor nameplate current, several advantages, including ease of coordination with an overload device, a smaller disconnect, and increased short circuit protection from a lower fuse rating, can be achieved. However, if sizing at this level prevents the motor from starting, it may then be necessary to increase the fuse ampere rating and it then becomes important to know the NEC sizing limitations. As of June 1, 2016, the US Department of Energy has mandated that newly manufactured electric motors will need to meet NEMA Premium® efficiency standards. As motor efficiencies increase, motor locked rotor currents can also be expected to increase. In addition to this, with across-the-lin
Read more

7/8 16UN Connectors that Provide 600 Volts and 15 Amps

TURCK announces new A-Size 3 and 4-pin 7/8 16UN powerfast™ connectors that provide up to 600 Volts and 15 Amps of power. These IP67 rated connectors provide a modular wiring system designed to handle high current applications for machine power distribution, while providing resistance to vibration commonly associated with conveyors, motors and material handling applications. The cordsets are available with a tray rated, exposed run PVC flexlife ® cable, with or without STOOW rating, and 14 AWG wires that allow you to replace hard wiring with a robust, quick disconnect system that saves the time and money spent installing a conduit system. The A-Size powerfast line offers male and female, straight connectors, standard and custom lengths, and pigtails or extensions. To make the system complete, fully encapsulated mating receptacles, with 1/2”-14 NPT mounting threads are available.
Read more