HAFA Conical rotor electric wire rope hoists are manufactured in compliance to Class II duty of IS 3938 / 1983.
The failsafe conical brake, which does not require any brake coil or electric circuitry makes these hoists most reliable, robust and ideal for heavy duty applications.
1. MOTOR :- The motor used in HAFA hoist is a conical rotor construction, 3 phase Squirrel Cage induction type. The motor is specially designed for Hoist & Crane duty. It has class 'F' insulation and the starting and stalling torques of this motor is 220 % and 290 % respectively of the full load torque. The motor is rated at 40 % CDF.
2. BRAKE :- Motors of conical rotor construction have an axial movement of the rotor, when started. The characteristic is taken advantage of in actuation of brake. When the motor is started, the rotor is pulled axially into the magnetic center of the stator field and the conical brake mounted on the rotor shaft, thus gets released. If the motor is put off or the power should fail, the rotor is moved back axially by the spring provided in the spring housing, and the brake is applied. The braking torque is 100 % above the motor torque at rated load. This safe and simple braking arrangement which does not require additional coil or electric circuitry has proved itself to be very reliable and foolproof, and it needs very little or almost no maintenance.
3. GEAR BOX :-The gear box is made of High grade Cast Iron. The precision spur gears are machined from alloy steel, and gear box is greased filled, Ball / needle roller bearings are used to mount the gears.
4. ROPE DRUM :- The rope drum is rolled & fabricated from tested quality plates and machined accurately. It is driven through an internal gear ring and is supported by large diameter roller bearing at both ends. Machined rope grooves and drum diameter confirming is IS 3938 ensures the best possible working conditions for the rope.
5. ROPE GUIDE :- The rope guide is made of S. G. iron castings base and is accurately machined to suit the grooves of the rope drum. This rope guide moves on the rope drum like a nut on the screw and prevents the rope from overriding and loosening. It also operates the limit switches provided in the hoist to limit the over hoisting and over lowering of the hook. The rope tighter moving along the rope guide ensures proper tensioning of the rope.
6. MAIN BEARING HOUSING PLATES :- All part of the hoist unit are mounted on bearing housing, plates thus forming an integral unit.
7. CONTROL :- The hoist is controlled by a pendant push button station. Supply to the pendant push button is of 110 volts as per IS specifications.
8. MICRO-SPEED :- All hoists can be fitted with a separate micro-speed motor, giving an additional lifting speeds of 1/14th, 1/10th, or 1/7th of normal speeds independent of load. |