Materials Archives - Sheedy Crane

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August 16, 2019by elite0

What are Hoist Slings?

While requirements will vary depending on the site and the details of the job itself, one thing is certain, there are a couple of different types of rigging slings that are useful for different situations. Hoisting is a staple service for us at Sheedy Crane.

Before discussing that, there are a few important safety tips to consider

  • You should always determine the proper dimensions and style of the sling needed for your application purposes. Selecting the right sling for the job is crucial.
  • It is not advisable nor recommended to tie knots in slings.
  • Its all about load management, knowing the limitations of the lifting device is paramount to a successful pick.
  • Building on that last point, you must always find the center point of gravity before picking up a load.

Wire Rope

Wire rope is created by interthreading several individual wires to create a large, thick rope. This can be observed when you see wire rope that has become frayed, individual pieces of the rope become exposed. This is called birdcaging and If you spot this, you’re well overdue to replace your wire rope. One of the best ways to avoid cracking or breaking of your wire rope is to use proper blocking/padding to make sure the rope does not bend acutely. Instead, a wider bend can be created so that the rope only bends within its levels of flexibility.

There are several factors that determine the strength of a wire rope. The thickness of the rope is the most obvious factor. A thicker rope is a better rope in most cases. All ropes have a total load limit and many modern ropes have a design factor of 5, which means that whatever the total load strength of the rope is, it should be divided by 5 and that will be the maximum limit for the actual load used.

Fiber/Synthetic Rope Slings

Fiber rope is typically comprised of nylon, polyester, and sometimes propylene. They can hold a significant amount of weight and are highly malleable which means they adapt to many shapes. Synthetic slings also have a long life cycle even in heavy use scenarios. The catch? They are highly susceptible to chemical damage. Acid or any type of caustic substance can easily chew through fiber ropes much faster than any other type. The issue with this is that the very material becomes weak but it isn’t as immediately apparent as other sling types. The material type of sling will determine the resistant properties it possesses.

Bay Area Rigging Professionals

Sheedy Drayage Co. is a historic company that has been in business since 1925. We have decades of rigging experience with various types of rigging slings in the Bay Area. Whether it involves operating a crane, heavy rigging, shoring, or requiring precise engineering solutions, you can bet Sheedy can do the job like no other—we’ve been doing this for a long time, after all. Visit our contact page to get in touch with the location of your choice so that you can have your rigging work done in a timely and diligent manner.


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September 1, 2018by elite0

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Difficult lifting or jacking jobs are like puzzles for those of us in the industry. We thrive on helping businesses solve difficult lifting safely and efficiently.

What are some of the most puzzling types of jobs we’ve come across in our years of heavy lifting?

Foundation Replacement

One of the most diverse jobs in lifting and support is the need for propping up buildings. An unsurprisingly common need in San Francisco is seismic retrofitting. That is, jacking up older buildings to upgrade foundations for earthquake proofing. The foundation replacement requires specialized jacks, frames, and lifting equipment, alongside project design co-ordination to ensure everything goes smoothly.

Seismic retrofitting requires a difficult balancing act where support columns are jacked up with temporary support, while base isolators are installed. With our list of accomplishments including San Francisco City Hall and the Benicia-Martinez Bridge, among some of the largest seismic isolation projects in the world, no job is too big!

Overhanging Roofs

Where an overhang exists, it’s hard to get a crane in position. This is where a type of crane called a flying jib comes in handy.

The flying jib is a counter-weighted arm, which allows the load weight to hang at a distance from the crane pick-up point, therefore allowing the item to be placed under an overhanging roof easily.

A flying jib can also be a pivoted and weighted arm attached to a crane for more diverse angles.

Awkward Shapes and Sizes

When an item is regularly shaped, it’s easy to pick up with standard equipment. When there are irregular shapes, off-center weights, and difficult attachment points, the means of securing the load can become more complicated. The solution to this is simple. However, if one of our non-standard rigging solutions doesn’t suit the item, then a custom rigging solution can be designed to fit, which will make critical lift planning a breeze.

Extremely Heavy Items

While the cranes and hydraulic locking jacks at Sheedy Crane can handle up to 500 tons easily, it’s not as simple as just putting a crane on a truck and setting it up to lift your load.

Firstly, large cranes require special transport, which needs permits and coordination. Then, assembly and rigging need critical attention to ensure the equipment is secure, and that it is structurally and mechanically sound. The rigging for the actual lifting often requires expert design by our specialty engineering team.

Finally, all the strength and safety aspects of the lift need to be thoroughly checked and certified by qualified engineers, in accordance with engineering and safety regulations, an extremely heavy item can’t have any risk of failure.

Specialist Rigging Design

For difficult jobs, a specialist rigging design is required. For complex jobs, professional engineers use 3D CAD modeling to complete the design. 3D modeling enables all aspects of a lift to be considered, from all angles, before the job begins.

Difficult rigging and lifting jobs are the ones we thrive on, so ask us if you need help planning your next critical lift. Contact Sheedy Crane today!


415-648-7171