During any lift plan, there are many things that need consideration, from the best piece of equipment to complete the task to the headroom available to complete the lift. Determining how much headroom your equipment is going to take up depends upon what type of equipment you will be using. We will take a look through determining the required headroom from the simplest calculations to the more complex.
Headroom comes in play on every project from indoor lifts with a gantry or fixed steel beam to a crawler crane set up on site.
For this week, we will focus on an indoor lift. For this example, we will assume the use of a steel gantry set at maximum height being used to hoist a boiler. A steel gantry from LGH carries a maximum height under the beam of 15’10” that will be used to lift a steam boiler with a shipping weight of 12,400 lbs and dimensions of 6.5’W x 12’L x 13’H.
In this scenario, you would require the use of two 5-ton steel setup gantries to accommodate the length and can get away with, assuming a perfectly balanced center-of-gravity (CG). Given the max height listed above, this means that we have just under three feet (34 inches) of available space above the unit for our rigging to fit within. Sounds like a lot, right? Let’s take a look at the headroom requirements of some of the options for this lift starting from the beam down.
- Beam Clamps: Given the weight and the equal CG, we can divide the shipping weight in half to 6,200 lbs and assume that is the weight seen on each gantry. Dividing that by the two clamps required means each clamp must handle 3,100 lbs so a 2-ton clamp is sufficient. Using a Riley 2-ton Superclamp model S1A rated for 4,480 lbs, this would eat up roughly 10 inches of headroom. Exactly two feet of headroom is now left above your boiler.
- Hand Chain Hoist: Using the same figures as above and needing your hoist to handle only 3,100 lbs, the most likely choice would be your 2-ton Coffing hand chain hoist that eats up another 15-inches of headroom. This leaves you with 9 inches of headroom left above the boiler or 9 inches of available lift. Keep in mind, the manpower to pull the chain makes this one of the more labor-intensive options.
- Electric Chain Hoist: An electric chain hoist will drastically cut down on time and labor but comes at a cost. To use a 2-ton Harrington SNER020L hoist, headroom required would come in at 22.6” which, when paired with the clamp, leaves you with only 1.5” of available space above the boiler unit.
- Air Chain Hoist: Much like the electric hoist, the convenience of using the air hoist comes at the expense of headroom. The 2-ton JDN Profi (NS) Series 2TI model eats up 19.6” of headroom so, while it leaves a bit more space, you are left with only 4.4” of available headroom/lift for the boiler.
- Low-Headroom or Ultra-low Headroom Trolley Hoists: This option may appeal if precision is required in the lift and you need to raise the boiler more than 9 inches, but it would be prudent to add end stops on the beam for safety if using this setup. Your beam should always be plumb and level to avoid unwanted trolley travel. By incorporating the trolley into the hoist unit, the required headroom is cut down to 16.5” on the low headroom model or 6.5” on the ultra-low hoist. This leaves a substantial 17.5” or 27.5” of remaining headroom, respectively. There is a caveat to these hoists, however. Beyond the potential for undesired travel of the trolley, the low headroom hoist weighs in at a somewhat manageable 107 pounds while the ultra-low hoist comes in at 395 pounds when fully chained up, which may likely affect which option is chosen.
Having looked through the options above, the clear winner is the hand-chain hoist for providing the greatest degree of portability combined with remaining space. If the gantry remains perfectly plumb and level throughout the lift and the weight of the trolley hoists is negligible, those options are best for remaining headroom/lift space. It may also be a great time to look into whether a skate system – whether air or mechanical – may make more sense if the unit doesn’t need to clear any obstacles.
As you can see, headroom requirements can add up rather quickly on any lift plan. For that reason, it is important to know how to calculate your headroom before starting a lift to ensure you have the space available. Not factoring, or even factoring incorrectly, any of the above values can stop a lift in its tracks.
For more information and assistance in selecting the best tool for any job, you can always reach out to your local representative at LGH, chat with our support staff at rentlgh.com or give us a call at (800) 878-7305 to speak with one of our rental desk representatives.