Deciding which gantry crane to buy isn’t easy. There are many considerations and options.
To help you make the most beneficial and cost-effective choice for your business and application, we have provided some high-level and comparative product information and reference materials below. Then we pose six questions you will have to answer if you’d like us to prepare a price quote for you.
- First, there is a quick overview of crane terminology.
- Next, we summarize our gantry product mix and provide a side-by-side comparison of our six standard gantry products.
- Finally, there is a short list of industry reference materials and contact information.
If “standard” does not work for you, we also have an equally broad range of custom and semi-custom options to choose from.
As always, if you have questions, let us know.
Questions To Ask Yourself
To start to narrow your model options, it’s best to think through your answers to six questions:
The weight of the load you want to lift will determine the maximum lifting capacity of the crane models you can choose from. Wallace has gantry models with capacities ranging from one-quarter to 15 tons.
Always specify the maximum weight of the load you plan on lifting.
Contact or call us (610-647-1400) if you have questions. We’re here to help.
Bear in mind whether the load will have to be lifted over equipment on the shop floor or whether there are any overhead obstructions or ceiling restrictions as this will reduce the amount of space you have available to lift a load.
Then the crane itself has parts and pieces (discussed below) that will have to be factored into your calculations.
Stacking
Stacking is an important consideration when deciding how high you have to lift the load. Stacking includes everything underneath the I-beam that can effectively reduce the crane’s lifting height potential. Stacking includes the space needed for the trolley, sling usage, and hoist, examples of which are shown below.
Wheeled (Push) Trolley | Spreader or I-Beam |
---|---|
Wheeled Trolley Hoist | Electric Hoist |
It is imperative to understand that a hoist must be suspended with a hoist/trolley combination or at least a beam clamp. You should never attach a hoist to the I-beam with a sling. Slings are frequently used to pick up both bulk materials and delicate or oddly shaped objects. While convenient, slings can add substantially to the “headroom” and thereby reduce the amount of space you have available to lift a load.
This image clearly shows that sling height is close to the headroom of most hoists, so make sure you are factoring that in when you are deciding on the height of your crane.
Headroom Basics
We’ll first define some headroom terminology and then give an example of how to factor this into your height calculations.
- Hoist Headroom – Hook-to-Hook Distances
- Hook Height – Distance from the top of the crane to the hook. Subtract this distance from the Overall Crane Height to see if a given crane will “fit.”
- I-Beam Depth – For a given capacity and span, this number cannot be changed.
- Trolley Headroom – Distance from the bottom of the I-beam to the top of the hook.
The sketch above shows a “typical” trolley and hoist mounted on a 12” I-beam. As stated before, when you start to consider all the heights for the crane brackets, trolley hook height, I-beam depth, hoist “hook-to-hook,” the amount of available space “below” the hook decreases rapidly.
If you want help, Wallace sales staff are happy to help you choose the correct crane and hoist/trolley combination to meet your lifting requirements. Contact or call us (610-647-1400) if you have questions. We’re here to help.
The need to lift loads over equipment is important when considering the necessary crane width or span. Does the crane have to move over an object or does the object have to move over the crane?
If the crane must move over the object, the crane will need to be able to “span” it. The crane span is the length of the i-beam. Wallace cranes typically span 8 to 35 feet.
Clear Span and Brace Legs
Tri-Adjustable, Hippolift, and Mighty Mite cranes all have brace legs. These legs keep the frame rigid while moving and provide additional stability in the line of travel parallel to the I-beam.
The clear span is the distance between the brace legs and where they intersect with the i-beam.
Contact or call us (610-647-1400) if you have questions. We’re here to help.
Before buying, make sure the location is suitable for the crane.
Wallace Cranes are designed to move on smooth flat, concrete surfaces. While the proprietary four-bar linkage ensures the casters are all on the floor, you should avoid moving the crane over obstructions and debris.
There are a few cautions to be noted about concrete flooring. Because the load of the crane is transmitted to the floor through the casters (essentially a “line load”), the flooring beneath a crane should be 3,000 psi (pound-force per square inch) concrete at least 18” deep with one or more courses of rebar. The standard Wallace casters, in either phenolic or steel core with polyurethane tread, are fully capable of smoothly running the crane across the floor at full load.
An option is to have the crane track mounted. For these cranes, typically with an electric motor drive, the casters are replaced with V-groove steel, running on a track (angle iron mounted on a plate). Wallace builds this track in-house with three different capacities, 1-5 tons, 8-10 tons, and 15 tons. The track sections are available in standard 5 and 10-ft lengths, with male and female sections for smooth running. The track is held in place with a Wallace Track Clip (a cast iron part) bolted to the high-strength concrete floor. Wallace also makes track with end stops and a removable transition section for high-traffic areas.
Contact or call us (610-647-1400) if you have questions. We’re here to help.
Working with the hoist vendors, Wallace can provide “food-grade” hoists and trolleys for either clean-room or harsh environments (chemical or outdoors). However, in many cases, standard grade equipment (available at far lower cost) is used instead of the costly stainless-steel equipment with stainless-steel chains. You can often get several years of life even in adverse conditions.
One of the ironies is that a crane for use in a cleanroom is frequently used in wastewater treatment. In a clean room, the unpainted aluminum I-beam typically does not “shed” particulate matter. And the lubricants used in the hoist (and the hoist chains), trolley, and casters have minimal outgassing.
Because of the use of corrosives like chlorine compounds or the need to run the cranes outside, aluminum is often preferred for both lightweight and weather resistance. Lightweight is often a key consideration as our cranes are frequently shuffled between sites or within a single site where there are no continuous paths between various tanks or pump locations.
Contact or call us (610-647-1400) if you have questions. We’re here to help.
To answer that question, you’ll need to consider whether the hoist and trolley will be manual or electric. If the hoist is electric, you’ll also need to specify the required voltage when placing your order.
Hoists with capacities greater than 2 tons generally require 3-phase electricity.
Conclusion
For more information about gantry crane standards, regulations, and guidelines, please consider the following:
- American National Standard Institute (ANSI): http://ansi.org/
- American Society of Mechanical Engineers (ASME): https://www.asme.org/
- Occupational Safety & Health Administration (OSHA): https://www.osha.gov/.
Call (610-647-1400) or contact us if you have questions or would like additional information about any of our products and services. We would be more than happy to assist you.