Extracted from the April issue of HOIST magazine
Manual Power
In a world full of automation and tech, it's the simplest solutions that are often the best. Two companies - one manufacturer and one rental firm - make the case for manual chain hoists. Tony Rock reports.
LGH is a UK-based lifting equipment rental company, with more than 50 years of experience and operations in North America and Europe, while Tiger Lifting manufactures and provides a full range of hoisting and winching products globally. In the following Q&A Phil Smith, European asset manager, and Andrew Williams, group safety, health. environment and quality co-ordinator, both of LGH, and Alice Inglis, director at Tiger Lifting, discuss why manual chain hoists remain an important tool within the lifting industry.
WHY WOULD SOMEONE CHOOSE A MANUAL CHAIN HOIST OVER AN ELECTRIC ALTERNATIVE?
Phil Smith: It's the cheapest option. The purchase price is significantly lower than an electric hoist. For the sort of brands we've got in the fleet... for a one-tonne electric hoist we would probably pay approaching £3,000. But we would buy [a manual chain hoist] for £90 to £100. That will be reflected in the sale rate and the rental rate as well. So it's a much cheaper option.
Alice Inglis: In the current climate, budget is a significant factor in project planning and the manual hoist will be cheaper than an electric or pneumatic [air]-hoist of the same capacity. In general, manual hoists will do what electric and pneumatic hoists do but are likely to be a more cost-effective option.
PS: Generally speaking, they're lighter too, size for size. You've not got a big heavy electric motor in there. Obviously, you don't need power, so that makes them more versatile- you haven't got to plug them in anywhere or rely on a power supply.
Andrew Williams: It's a versatile hoist because it's lightweight. It's something you can move from A to B very, very quickly.
Al: [They are] easier for the operator to manoeuvre and position, which can be an important factor in the planning and implementation phase for a lifting operation.
PS: You can also fleet' with them. So, with certain models, you can transfer loads from one hoist to another, effectively bringing the load out at an angle to meet another hoist. You generally can't do that with electric hoists. You'd normally see that maybe in a ship, where they're lifting something in a boiler room, and they will transfer it from one end to the other by using this 'fleeting' operation.
Al: Tiger Lifting's Professional range of manual hoists are perfect for projects where fleeting loads is critical, whether that be in tight headroom spaces or open ground where a power supply is not available. These hoists have our patent protected Quad Cam brake system and have undergone a full and comprehensive testing regime that was drawn up by industry specialists and Tiger's mechanical engineers to provide evidence that these units can be safely used for fleeting and cross-hauling applications up to 45 degrees without de-rating [operating at less than its rated maximum capability].
AW: One of the key elements to a chain block [another name for a manual chain hoist] that is not focused on these days is it's precision. From a lifting point of view, where you are using an electric hoist and pressing a button, you're relying on waiting for that motor to cut out. Now it takes a millisecond or whatever for the motor to stop, but that can [equate to] a couple of millimetres going down, and if you're trying to land a load on a precise place - maybe over a shaft or over some fixing bolts - the manual hoist, because it's slower and you've got more control over it, is more precise in lowering the load down, rather than with a clunk, if you will, that an electric hoist can potentially give you.
On some of the more expensive electric hoists, mainly used with overhead cranes. you can buy items that are controlled and precise, but when looking at the rental market, a manual chain will be much more precise.
IN WHAT ENVIRONMENTS IS IT BETTER TO USE A MANUAL CHAIN HOIST?
PS: With electric, of course, you can't use that in areas where there's any risk of spark whereas with hand chain hoists you don't have the same risk.
Al: They can be used in environments that might not be suitable for other types of hoists, or when no electrical power nor air supply are readily available at the operation site. Spark-resistant chain blocks and lever hoists [a type of manual chain hoist] are built for use in potentially dangerous areas - environments which may be explosive or highly volatile, where an electric chain hoist wouldn't be suitable. At Tiger Lifting we have a full range of hoisting and lifting equipment that meets the requirements of the ATEX Directive 2014/34/EU, with third-party verification. This includes upgrades to hooks, internal components and chain where required to minimise the potential for explosion. Using hoists specifically engineered for extreme environments is a key benefit of these types of manual hoists.
AW: Where there is a shutdown on a major industrial site - say, a petrochemical site - they would want something that they would be able to bring in for short or long-term rental. We would obviously have serviced it, examined it, supplied it with all the current paperwork and legislation that it would need on that particular site. The company can go out and use the equipment - take valves out, gearboxes, whatever it may be for refurbishment. They can then take the chain block down from where it's hung and take it to another part of the plant to do another piece of work with it etc, and at the end of the shutdown send it back up to us, and we do all the refurbishments on the equipment, making it safe to use on the next rental.
It's very much 'get it in use it, put it away, send it back, and [repeat for] the next shutdown. The company would bring in a brand new set of chain blocks - nice and fresh- and start all over again.
Al: in an offshore environment. Tiger Lifting Specialist manual hoists have thousands of hours of evidence of comfortably withstanding the harshest of environments including subsea and multi-immersion applications. We have a history of hoists that have been working in marine environments for more than ten years that are still in the field today and performing to the highest of standards. It is very much dependant on the manufacturing quality and finish of a manual hoist as to how it will stand up in a demanding environment.
WHAT ARE THE DISADVANTAGES OF A MANUAL CHAIN HOIST?
PS: Blinking hard work! Every user would obviously prefer the powered option - we all want the easy way of life. don't we? They're labour-intensive and obviously quite slow as well. Because of the way the gearbox works with the mechanical advantage [a measure of the force amplification achieved] there's a lot of pulling the chain around to move the load a small distance. It's quite a strenuous process.
Al: An electric or pneumatic hoist will generally lift a load much more quickly than a manual hoist, and at the press of a button, whereas the manual hoist requires human effort. So speed and human fatigue may be considered to be the negatives of using manual hoists.
AW: If you had to do the same lift four, five, six times during the course of a day, you wouldn't want to have a hand chain block because it's slow. The manpower that you would need to use it would be getting tired and no doubt ratty. You'd obviously have to look then for a powered option. Repetition is the key: if you're doing the same lift day in and day out, hour in hour out, then you want to be looking at a powered option But as for disadvantages, it's a very short list because you can do so much else with chain blocks. There are many more pros than cons
PS: Another point is the excess chain can get in the way. What you traditionally find with most powered hoists, particularly electric, is they have a chain collecting bag And although they are available on manual hoists, you don't see them very often, so you will have all this excess chain often hanging down and around the working area. That can be a little bit of a negative.
IS THAT A SAFETY CONCERN?
AW: It can be. You might be stood on the ground floor level, taking the hoist, the load, down a hole or shaft, so you could actually get a surplus chain on the floor level where you're stood. But again, in terms of disadvantages, it's a very, very small point.
WHAT DIFFERENTIATES ONE MANUAL CHAIN HOIST FROM ANOTHER PRODUCT?
PS: Generally speaking, the basic design is the same. The mechanical advantage is very, very similar, distance of travel, the effort required. They're all very similar.
AW: In relation to the pinion shaft, load sheave, ratchet system etc. they're all pretty much of a muchness.
PS: The principles are the same.
AW: Unless you're talking about the 3605.
PS: Yale, or Columbus McKinnon, manufacture a product called the Yale 360. With the traditional hand chain block you would tend to operate it from directly below the load or you can stand away from it, so you're at a slight angle. These 360s can be operated from any position. If you were on top of a mezzanine, you could theoretically still operate the hoist [above the load].
In terms of brands, there's Tiger, Nitchi, Yale, Tractel, Planeta... There are probably a few Chinese ones we could add to that as well. A lot of the parts originate in the Far East anyway, so they are probably all Chinese or Japanese or Taiwanese at some point in their life.
Brand isn't that important... with rental: customers just see it as a tool they're going to have for a few days, a few weeks, then hand back. But from our point of view, it's important that our equipment is of the right brand and right quality, for longevity of service. There are people in the rental industry that will literally buy a 10-ton hoist for £30 to £40 and throw it away at the end of the year. We'll probably pay £100 or more with the view to keep it running for five to seven years, maybe longer depending on, the utilisation.
Customers don't normally specify [a brand], but that's not to say it never happens - you will get some customers that will say 'I want to rent 100 hoists, but they must be Tiger, which, to be honest, is pretty much the standard in the UK.
That's not to say there aren't any other hoists available - of course, there are - but most of the big rental companies offer Tiger as the leading brand.
In Europe, we stock a lot of the Nitchi. It's a Japanese hoist, which, is like a Swiss watch - in cost and the way it works. The functionalities are exactly the same [as a Tiger] - it won't pick up any more or any less, but the actual mechanics of it, when you're operating it, you can hardly hear it.
AW: It should be said that even though there are a lot of different brands out there, even though the principles of the units are the same, you can't interchange parts from one to the other. It's not like a Ford car, where you could nip down to Halfords and get Halfords own brand to change the spark plugs. You would have to put Tiger products in a Tiger hoist, Nitchi products in a Nitchi hoist.
WHAT IS YOUR MOST POPULAR TYPE OF PRODUCT?
PS: The 1.0-tonne hand chain hoist, probably at 6m height of lift. That's where most of the action is - 3m and 6m because that covers most eventualities.
AW: I think it's safe to say it's always been called the 'bread and butter'.
PS: If you look at our fleet across the UK and Europe, we've got just over 3,000 hand chain hoists and probably 15-20% of those are 1.0-tonne 6m because that is the most popular hoist. There's probably 500 or 600 in the system across the 3,000, so it's definitely the most popular.
WITH THE WORLD EMBRACING MORE TECHNOLOGY, SUCH AS AUTOMATION, HAVEN'T YOU SEEN A DROP IN DEMAND FOR SIMPLER SOLUTIONS, SUCH AS MANUAL CHAIN HOISTS?
PS: I don't think so. Over the years there's probably been a subtle move towards powered hoists, but not in a major way.
AW: From a from a financial point of view, it's cheaper in the long run, if you've got a permanent fix, to put up an electric hoist because you're not constantly pulling the chains out, but from a rental point of view I think the demand is still there.
PS: Across our European fleet, 82% are hand chain blocks. This is the volume, not the value. Electric is only 6% and air hoists are 12%.
Al: It is difficult to foresee a time where manual hoisting is considered obsolete as budget will always play its part with industries continuing to look at ways of operating in a lean and sustainable way. For the renewables sector, manual hoisting plays a key role and will continue to do so as the sector continues to play a prominent role in the future of green energy, whether that be utilising manual hoists in the construction of offshore wind farms, or the ongoing maintenance activities currently in place throughout the green sector.
Manual hoisting plays a predominant role in all spheres of industry - renewables, construction, aviation, entertainment, oil and gas exploration, overhead transmission lines, mining and so on. It is hard to envisage a time where there will be no requirement for manual hoisting.
