We often use the phrase “true vertical lift” when we describe the operations conducted through the use of overhead cranes. True vertical lift means that a hoist is able to lift a load straight up without involving any lateral swing. Vertical lift is facilitated through the use of equipment that works through double reeving. This is a type of configuration that involves two ropes coming out of a grooved drum from each end. When a load is lifted by an overhead crane, the ropes swirl around the grooved drum from the ends and towards the midpoint. This is what allows the load and the hook to remain aligned with the drum’s centreline, which, in turn, promotes a vertical lift.
Cranes that promote true vertical lifts can lift heavier loads in the 25-100 tonnes range. This is mainly because of the fact that the weight is equally shared by the two or four ropes. Cranes which facilitate true vertical lift are ideal for operations that may get disturbed due to a slightest side-to-side movement of the hook. This includes precision assembly operations and lifting operations in the aerospace industry.
Single reeving, in contrast, is one of the simplest and most commonly deployed reeving options, which works perfectly with lighter loads that weigh less than three tonnes. Hoists that are not used for precision lifting operations can be made to work well with single-reeving option. In a single-reeve setting, the wire rope twirls around the drum in a single layer and as the wire rope continues to rise, the hook gets raised too in a horizontal fashion.
Notably, chain hoists can facilitate better vertical lifts compared to wire rope hoists that move the load laterally to a certain extent during the lifting process. It is much more common to see a single fall chain hoist. However, this does not imply that wire rope hoists exhibit inferior lifting performance compared to chain hoists as in most cases, you will find the lateral motion to be negligible.
Electric Wire Hoists
Electric Wire Rope Hoists from leading manufacturers at leading prices. We advise from the most comprehensive range of technologically advanced Wire Rope Hoists based on your specifications. New or Used up to 50 Tonnes in Monorail, Low Headroom and Crab Unit models for single and double girder overhead cranes. We also offer installation and servicing on all types of hoists.Click here for more information
Inspection services from the experts, we offer testing, inspection, certification and reporting on all types of Overhead Cranes and associated Lifting Equipment.
Remember: Maintenance Prevents Breakdowns. All of our maintenance is carried out in accordance with LOLER requirements by fully competent and trained engineers. Call our Service Department Today!
Click here for more information
George Beardshaw -RMD Kwikform
We have just had new remote control gear fitted to our 5 ton crane. Great ...Click here for more testimonials
- Understanding True Vertical Lift19th January 2017 Vertical lift is achieved when there is no side-pulling action, it is recommended that all loads are lifted truly vertical and never to involve side loading as this has ...
- Understanding Load Sway And Tips To Prevent It3rd January 2017 Load sway can be a nightmare for crane operators, learn and understand more about load sway and how to tackle the problem in this article.
- A Brief Overview of Permanent Lifting Magnets and Electro-permanent ...25th October 2016 A lifting magnet is an electromagnetic device that is used to lift metal items in a safe and secure manner. Different industries undertake different applications that may demand ...