True Torque Fluid Couplings Selection Guide Type HF
32Pages

N O I Protecting your system, enhancing component life, from beginning to end. T 521-110 H E F A L K C O R P O R A T True Torque™ Fluid Couplings

True Torque Fluid Couplings Economical soft starts, with smooth acceleration. Shock-load protection ™ From underground & overland belt conveyors to crusher and mixing applications, equipment professionals are constantly seeking better technology to protect critical production systems against the effects of damaging shock loads. And when it comes to eliminating sudden/jarring starts, or preventing system failure/deterioration due to overloads, nothing outperforms the system-saving capability of Falk True Torque fluid couplings. • Unmatched, cushioned soft start flexibility, at an economical...

• NEW Longer starting profiles and softer starts • For Sizes 1420HF & larger, adjustable metering orifices regulate the passage of fluid from the delay fill chamber into the working circuit, further softening the start. • For sophisticated belt conveyors, consider Type HFDD. The extended delay fill chamber permits initial start factor as low as 40% of the full load torque, dramatically reducing shock & stretch to the belt at startup. Use of the extended delay fill chamber (HFDD) is recommended for conveyors subjected to unloaded starts, those with concave sections, those with low inertia,...

Basic Types The non-delay fill option (HFN/HFR) provides soft start, including a short delay (example: 5-10 seconds) in the acceleration of the load, and is a good choice when overload protection or increased starting torque is a primary requirement. Complete drive systems from Falk But Falk’s capability isn’t limited to just selling a component, we sell drive systems incorporating the gear drives, couplings, backstops, brakes, guards & motors, all mounted on a bedplate, swing base or alignment free assembly. Plus, our ready availability keeps you producing… even in the most remote places...

Selection Guide 521-110 June 2004 Table of Contents Benefits of a Fluid Coupling . . . . . . . . . . . . . . . . 6-7 Mounting Arrangements . . . . . . . . . . . . . . . . . . . 8 Basic Types . . . . . . . . . . . . . . . . . . . . . . . . . 9 Principles of Operation . . . . . . . . . . . . . . . . . 10-11 Accessories . . . . . . . . . . . . . . . . . . . . . . 12-13 How to Select . . . . . . . . . . . . . . . . . . . . . . . 14 Fluid Coupling Identification . . . . . . . . . . . . . . . . 15 Availability Table . . . . . . . . . . . . . . . . . . . . . . 15 Quick Selection Tables . . . . . ....

F A L K Benefits of using a Falk fluid coupling Soft cushioned starts Without the fluid coupling, the motor instantly transmits its locked rotor torque (starting torque) to the driven machine (point A at right). Then, it quickly reaches and applies the breakdown torque (point B). For common applications, locked rotor and breakdown torque often approximates 200% or more, of the motor nameplate rating. Damage can result if the required break-away starting torque of the driven machine is significantly less, the machine will be abruptly accelerated to rated speed. With a fluid coupling...

Reduced current draw when starting The electric current draw at startup is dramatically reduced when a fluid coupling is present. The motor starts without any meaningful load yet applied by the driven machinery (point A, Figure 1). In the absence of load, the motor quickly accelerates to approximately 90% of its full load speed (point B, Figure 1). The result is that low current draw (point C, Figure 1) is achieved within several shaft revolutions. At this point the inertia of the motor has been accelerated, and the application of load from the driven machine will not cause subsequent...

Mounting Arrangements Gear Coupling Mount Type HF20 (Exposed Bolt) • Most Economical • Drop-in/drop-out servicing (no need to move connected • Readily shipped from stock components Steelflex/Hollow Shaft Mount Type HF31 (Setscrew Retention) Type HF32 (Keeper Plate Retention) • For limited shaft gaps/Steelflex grid coupling at driving end • Hollow shaft bored to the order • Type HF31/available Sizes 320-1 480/secured to driven shaft with (2) setscrews/allow clearance for setscrew wrench driven shaft with keeper plate & retention fastener/drill & tap driven shaft end for retention fastener •...

Basic Types Non Delay Fill (HFN) and Inactive Delay Fill (HFR) l l l l l l Delay Fill (HFD) l Soft, cushioned start with a short delay in the acceleration of the load (Example: 5 seconds) Satisfactory soft start for many common applications Best choice for overload protection (Page 6) Good choice for increased starting torque (Page 6) All fluid remains in the working circuit HFR (plugged delay fill chamber) furnished when HFN not available RUNNER l l l l Softer, more cushioned start with longer delay in the acceleration of the load (Example: 12 seconds) Excellent choice for belt conveyors,...

F A L K } CASING Principles of Operation RUNNER WORKING CIRCUIT IMPELLER Introduction The working circuit is defined by the Casing, Impeller, and Runner. A conical baffle is attached to the Impeller, and a flat baffle is attached to the Runner. The Impeller and Runner each represent half of a hollow torus, each with flat radial vanes. Torque transfer takes place as follow. Driving End (Input) mechanically transfers torque to the Casing. Casing mechanically transfers toque to the Impeller. Impeller transfers torque, via the Fluid, to the Runner. Runner mechanically transfers torque to the...

Overload – stall Should the load torque increase, the slip will increase, which causes the runner to drop in speed. The coil of fluid circulating between the impeller and runner will expand to provide additional torque. The extent to which this coil can expand is limited by the flat baffle on the runner. Consequently fluid couplings provide inherent overload protection. If the increase in torque causes the fluid in the working circuit to expand to the point of contacting the baffle, the coupling will stall and slip will be 100%. This continuous high slip generates heat and the fluid...