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What's the difference between supplying a new crane vs supplying second hand?

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(@edwin)
Anggota Terkemuka
Joined: 2 tahun ago
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I saw a friend in the forum asking how to buy a used crane. From this, it occurred to me that besides being cheaper than a new crane, there might be other differences between the two. So I googled and found another article explaining the difference in the supply chain between new and used cranes. I am posting this article for your reference. I think that existence is reasonable. Although I am skeptical about buying second-hand cranes, I believe there must be a way to take into account both cheap and easy-to-use cranes.

WHAT'S THE REASON FOR THIS ARTICLE?

Before we start, it's worthwhile pointing out that this is in no way meant to be a put down of the purchase of second hand cranes. When done correctly, purchasing a second hand crane is completely fine, so long as you are provided with all of the required documentation and that the supplier is actually doing everything that they should be from their side.

There are lots of reputable second hand crane suppliers out there, that without a doubt will supply you equipment that is technically correct and safe however like every industry, there’s companies who cut corners and don't have all of the required documentation to back up the equipment so you just need to be careful and do your due diligence before going ahead with a purchase.

HOW CAN I MAKE SURE THAT MY SUPPLIER IS REPUTABLE?

The Lifting Equipment Engineers Association (LEEA) is established across the world as the leading trade association for all those involved in the lifting equipment industry and by using a Full LEEA member you can be confident that the equipment you are being supplied is compliant with current legislation.

You can check if your lifting equipment provider is a Full LEEA member by searching on the membership database.

WHAT’S INVOLVED IN THE SUPPLY OF A NEW OVERHEAD CRANE?

In the section below, we've outlined the steps that are carried out when you purchase a new overhead crane from Hoist Inggris.

You'll notice that the steps are tailored so that we can ensure that you are getting a piece of equipment that is designed specifically to suit your application and that the necessary technical information and guidance is provided to ensure that there are no issues when it comes to the installation and commissioning of the crane on your site.

  • Review of requirements with the customer (site visit may be required)
  • Quoting stage and confirmation of specification.
  • Submission of full design and technical package, consisting of calculated wheel loads imposed by the crane, general arrangement drawings and imposed loadings to the supporting structures (floors, walls, ceilings etc.)
  • Formalised sign off of drawing approval package by the customer (site visit may be required at this stage if not completed at quote stage).
  • Issuing manufacturing drawings to our production department.
  • Ordering of crane kit components (hoist, travel motors, crane panel etc.)
  • Ordering of raw materials (if required) such as I-beams, sheets, flat bars, or hollow sections.
  • Cutting down of materials and fabrication of the crane.
  • Quality check and dimensional check to ensure that crane and end carriages are square. (If the end carriages aren’t square then the long travel wheels will wear frequently and this is not normally a part that needs to be changed at regular intervals).
  • Painting of the crane components. This is generally a wet paint finish or a powder coated finish depending on the overall size of the equipment and operating environment.
  • Assembly and testing of the crane. The crane is then built up in our workshop by our LEEA accredited engineers and tested prior to dispatch.
  • Compilation of the technical file, consisting of design calculations, general arrangement and manufacturing drawings, full material traceability certificates, manufacturing records from our coded welders, job sheets and test certificates from our LEEA accredited engineers and quality control log prior to shipment.
  • Delivery of the equipment to site.
  • Installation and commissioning of the crane, including load tests as required.
  • Basic system familiarity training with operatives on site in the safe use of the equipment.
  • Issuing of required owner's documentation to the client such as EC declaration of conformity, O&M manual and reports from install.

WHAT’S INVOLVED IN THE SUPPLY OF A SECOND HAND OVERHEAD CRANE?

Now, this is where it gets a little more complicated as the requirements for the supply of a second hand crane completely depend on the circumstances of the supply.

For ease, we’ve split this into the following 3 categories:

  • Supplying a second hand crane without any modifications
  • Supplying a second hand crane with "minor" modifications
  • Supplying a second hand crane with "major" modifications

UPPLYING A SECOND HAND CRANE WITHOUT ANY MODIFICATIONS

Let’s say for example that a second hand crane and accompanying gantry steelwork have been purchased and removed from one customer’s location and is being re-supplied for installation at a new customer’s site.

If the equipment remains within its original operational parameters; (eg. the SWL, span, height of lift, hoisting and travel speeds all remain the same) and the crane was supplied after introduction of the Machinery Directive and is CE marked, then the supplier of this equipment can still use the original EC declaration of conformity.

Overheadcrane

The imposed load case on the supporting structure from the overhead crane and gantry steelwork should remain the same as the original supply however, if this information is not available additional design work may be required as this should be submitted so that the customer can validate that the floor is adequate for these loadings (generally this will be done by a structural engineer).

If the information is not available, then the second hand crane supplier will need to almost “reverse engineer” the crane design to find out crucial information such as spans, wheelbases, component weights, section sizes, steel grades etc. so that the required calculations can be carried out correctly.

Once installed at the new site/location, a thorough examination must be carried out by a competent person prior to the crane being allowed to re-enter service and as part of the test, a load test should be carried out.

SUPPLYING A SECOND HAND CRANE WITH “MINOR” MODIFICATIONS

Let’s say for example that a second hand crane and accompanying gantry steelwork have been purchased and removed from one customer’s location and is being re-supplied for installation at a new customer’s site. However, whilst some of the original parameters remain the same (eg. the SWL and the hoisting and travel speeds), modifications need to be carried out.

Like the previous example, the crane was supplied after introduction of the Machinery Directive and is CE marked.

The modifications could be one or more of the following:

  • Reduction of the span.
  • Modification of the control system (eg. fitting the crane with a radio control system).
  • Replacement of worn components with new items of similar specification.
  • Replacement of hoist unit with one of the same SWL and maximum hoist speed.

Overheadcrane

Regulation 10 of PUWER requires the user to ensure that any item of work equipment that was first provided for use in the workplace after 5th December 1998 is designed and constructed in compliance with the EHSRs of the Machinery Directive relevant at time of supply. Even considering the modifications above the supplier may use the original EC Declaration and CE marking as evidence that the crane met the EHSR’s at time of supply. A new assessment against the EHSR’s is not required, however due to the modifications above the following additional documentation should be provided:

  • A statement of the changes made to the original crane including the reference of any standards or other specifications relevant to the changes. This should be backed up by a technical file.
  • Confirmation from a structural engineer that any reduction in span or change to the mounting arrangement will not have any detrimental effect on the crane.
  • New or revised wiring diagram (where appropriate).
  • New or revised instructions for use and maintenance (where appropriate).

Like the previous example, the imposed load case on the supporting structure from the overhead crane and gantry steelwork should remain the same as the original supply however, if this information is not available or not valid anymore due to the modifications carried out, then additional design work may be required as this should be submitted so that the customer can validate that the floor is adequate for these loadings (generally this will be done by a structural engineer).

If the information is not available, then the second hand crane supplier will need to almost “reverse engineer” the crane design to find out crucial information such as spans, wheelbases, component weights, section sizes, steel grades etc. so that the required calculations can be carried out correctly.

Once installed at the new site/location, a thorough examination must be carried out by a competent person prior to the crane being allowed to re-enter service and as part of the test, a load test should be carried out.

SUPPLYING A SECOND HAND CRANE WITH “MAJOR” MODIFICATIONS

Let’s say for example that a second hand crane and accompanying gantry steelwork have been purchased and removed from one customer’s location and is being re-supplied for installation at a new customer’s site. However, most of the original parameters have been changed.

Like the previous example, the crane was supplied after introduction of the Machinery Directive and is CE marked.

The modifications could be one or more of the following:

  • Increase of the span.
  • Increase of rated capacity.
  • Alteration of the connection between the bridge girder(s) and the end carriages.
  • Changes affecting ratio of end carriage wheel centres to span.
  • Hoist is modified from two speed/single speed to variable speed drive (Inverter)
  • Hoist or crab unit is to be modified, such as the number of falls, modification to drum length or hoisting speeds.
  • Fitting of multiple hoists instead of a single hoist.
  • Replacement of independently controlled multiple hoists. (e.g. replacing the hoists for a single hoist with a lifting capacity equal to that of the multiple hoists)

Overheadcrane

The modifications are such that the crane would now need to be considered as a new piece of equipment and therefore the original EC declaration of conformity is no longer valid. The second hand crane supplier is now classified as the manufacturer and as the crane needs to comply with the Machinery Directive, a new technical file should be prepared.

This should include an assessment against the Essential Health and Safety Requirements of the Machinery Directive and on completion an EC Declaration of Conformity should be prepared and placed in the technical file. The CE mark should be affixed, and the owner of the equipment be provided with a copy of the EC declaration.

The assessment must cover the whole design of the crane and should not be just limited to the parts affected by the modifications.

There are some additional questions that come with these sorts of modifications:

  • When carrying out the above modifications, how do you validate that the section size used is still adequate for the increased capacity and/or increased span?
  • When increasing the span of the crane, how does one verify the method used is suitable (should the bridge beam be replaced completely as 1 section or are fish plates/welding plates in between 2 parts adequate for the safe operation of the crane?
  • When increasing the span, how does one confirm that the end carriages and wheelbase ratio are not going to be affected by this change as these are normally designed to suit and the additional weight would not have been considered in the original wheel loadings?

As you can see, there are so many unknown variables and by the time that all of these points are satisfied to the level of which they SHOULD be (through structural analysis and design validation), it would likely be more economical to just start from scratch with a PURPOSE BUILT CRANE for the specific application.

Unlike the previous examples, the imposed load case on the supporting structure from the overhead crane and gantry steelwork will completely differ from the original supply and therefore additional design work will be required as this should be submitted so that the customer can validate that the floor is adequate for these loadings (generally this will be done by a structural engineer).

Once installed at the new site/location, a thorough examination must be carried out by a competent person prior to the crane being allowed to re-enter service and as part of the test, a load test should be carried out.

You as the owner of the equipment are responsible for making sure you get a copy of the EC declaration of conformity for the new crane, from the person who is selling it to you. Not the documents from what appear to be the original manufacturer as they are no longer the manufacturer once the modifications have been carried out.


   
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