Manufacturing Cranes in the USA for 50 plus Years             

CORRECTLY SPECIFYING A CRANE:  The three most important factors that need to be known:

   1.   How much weight will be lifted

   2.   How far out from the center of rotation is the load?

   3.   How often will the lift be made?

MAXIMUM CAPACITY : Advertised maximum capacity is a statement of the maximum winch capacity of the crane.  Liftmoore does not recommend purchasing a crane for use at its maximum lifting weight.  A cranes capacity at a particular load radius is determined by its Moment Rating. Understanding this is essential to getting the crane you need.

MOMENT RATING : Moment Rating is a mathematical equation determined by the WEIGHT times the LOAD RADIUS.

LOAD RADIUS: : This is a measurement from the center of the crane’s rotation axis to the center of the load in a horizontal plane.

WEIGHT:  The amount of weight to be lifted includes all rigging used, including the travel block, any chains or slings, and the hook.

        Example:

     A crane with a max lift capacity of 10,000 Lbs with a 72,000 Ft-Lb. Moment Rating.

     72,000 Ft.-Lbs. divided by 10,000 Lbs. equals 7.2 Ft.  This is the maximum load radius with this load.

     For a 12 Ft. radius the maximum load is:  72,000 divided by 12 equal 6,000 Lbs.  Note the rapid decline in capacity as the radius increases.

     At a 20 Ft. radius the capacity is only 3,600 Lbs.

CONTINUOUS ROTATION:  Many crane manufacturers claim to have continuous rotation, however, the rotation may be limited at 375 or 400 Degrees at which point the rotation will stop and must be reversed. This limitation must be considered when positioning the truck to perform the work at hand.

UNLIMITED ROTATION:  Liftmoore cranes typically have unlimited rotation. There is either an electric or electric and hydraulic swivel that allows this important feature. As a result there is no limitation by a mechanical or electrical stop on the crane’s rotation.

DUTY CYCLE:  Hydraulic crane duty cycles can be nearly continuous depending upon reservoir size and hoist operating temperature.  Electric crane duty cycles should be limited to 10 to 15% when heavy loads are being lifted. Auxiliary batteries are required by these cranes.

BATTERIES:  All 12V DC powered cranes will benefit by having a battery as large as possible located near the crane. Motor and Solenoid life will be extended if an additional battery is mounted near the crane. The two batteries under the hood of a Diesel engine truck are NOT adequate to power an electric crane. The DC voltage line loss increases dramatically as the length of wire is increased and the voltage at the crane can only be maintained with an additional battery near the crane.

POWER DISCONNECT:  Turning off power to the crane will increase the life of its electrical components. Electrolysis causes corrosion which will reduce component life and may cause intermittent electrical problems. All Liftmoore cranes are supplied with a master disconnect switch or a mecon quick disconnect for disconnecting the crane from its electrical power source.

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