Archive for the ‘HUK – Discussion Topics’ Category

When does your hoist need an general overhaul or be replaced ?

Tuesday, February 23rd, 2016

Well that’s an interesting question… all hoists currently operating within the UK and European marketplace should be designed and manufactured in accordance with the Machinery Directive (2006/42/EC) and have an EC Declaration of Conformity by the Original Equipment Manufacturer (OEM).

Hoists are manufactured with 10 years of serviceable life before a major overhaul or replacement is required. The ten year service life may not necessarily be a physical ten years of operation, but may be used up more quickly or slowly based on how the machine is being operated during its working life.

In order to help evaluate the working life of a hoist you need to be able to calculate how much of the original manufacturers Safe Working Period exists after your lifting operations have occurred.

All hoists start off life with a 100% SWP and as they are used the percentage will reduce until its reaches 0%, whereby a General Overhaul (GO) is normally carried out by the manufacturer or their representative. If a general overhaul is not possible or financially viable then the unit should be replaced as the serviceable life has been exceeded.

When you are buying a new hoist you need to careful select a unit which has the correct duty rating for your particular lifting operations, so that you will have a machine which does not use its SWP too quickly and require replacement.

Safe and reliable load handling are a primary concern to ensuring and maintaining safety during all lifting operations. Wear and tear due to normal use can easily result in potential problems, if they are not addressed in good time, so  knowing your remaining SWP can help with early detection of hazards caused by material fatigue, can help with predictive maintenance and also give early notification of a required general overhaul or when replacement of the hoist should occur.

All users of hoists should be aware of the remaining SWP on all the hoists in their possession and it is recommended that a log book detailing all lifting operations is kept for each unit.

Keeping a log of all lifting operations is not something I have seen done by users of hoists in the past, but there are other methods available to help give an awareness of running / operating time on each of the hoist units.

Hours in service meters fitted to your hoist do help you to evaluate how long the hoist has been operating, but these types of devices only log the amount of time the mains contactor in the hoist has been energised and not how long the electric motor has been actually running to lift and lower the load.

Predictive maintenance devices which monitor all lifting operations and weigh the load lifted, running times and lots of other hoist parameters can be used and these are probably the most accurate way to understand the hoist status, as they constantly recalculate the remaining SWP. These devices are not normally fitted to equipment and could be a costly addition to your existing hoists or any new ones you are purchasing, plus its only normally electric wire rope hoists that have predictive maintenance devices fitted to them, so are not generally available for electric chain hoists.

In order to help a user evaluate their remaining Safe Working Period (SWP), we have developed SWP calculator utility which will help you try to predict when a hoist is at the end of its working / serviceable life and should undergo a General Overhaul (GO) or be replaced.

The utility is been produced specifically for users who do not have a log book of lifting operations available for the unit in question and there are no other methods of evaluating the SWP.

You also need to bear in mind that during the hoists serviceable lifetime, the unit should still undergo regular servicing in accordance with the manufacturers recommendations and also be thoroughly inspected on a regular based by a competent person under the Lifting Operations and Lifting Equipment Regulations (LOLER), in the United Kingdom.

Our SWP calculation utility can also be used to check if a hoist is suitable for particular application as buying an M3 / 1Bm duty rated hoist for an application which always lifts the maximum load or runs for a prolonged period may not be the best decision as the SWP will be used up quicker.

In order to check if a hoist is suitable, key in data of how you would like to use the machine in the future and adjust the duty factor variable to see the effect on the machine operating at that level for the period of time you want it to operate. From that output data you will know if the machine is suitable or not. If you haven’t already purchased the hoist, you will know the duty of the hoist you need to purchase do your lifting operations.

The SWP calculation utility has been designed to output a PDF document via email that can be printed for each hoist in your possession and updated periodically during the hoists lifetime to help predict your remaining SWP.

The indicative calculation of remaining serviceable life of the hoist can then be  held with the EC Declaration of Conformity, service reports, LOLER inspection reports and any other relevant health and safety documentation for the unit.

Click on the following link to use our free utility: SWP Hoist Calculation

Remember: Safety Above All