A digital crane scale, while ruggedly constructed to perform heavy lifting and weighing functions, is also a precision instrument that must be maintained on a regular basis. While maintenance is important for any weighing instrument from an accuracy standpoint, heavy-duty crane scales must be checked regularly to avoid a mechanical failure that could cause a load to drop with potential disastrous results.
Crane scale manufacturers such as Kern, whose products are offered by Tovatech, provide maintenance instructions as part of their operations manuals. We’ll use here as an example the Kern HTS industrial hanging scale available in four models with maximum weight capacities from 1500 to 10,000 kg (~3,300 to 22,000 pounds) The scale is powered by a rechargeable battery and is shipped with an infrared, battery-powered remote control with a range of approximately 25 feet.
Crane Scale Maintenance Guidelines
Key lifting components on crane scales include shackles, hooks and anchor eyelets. Maintenance checks on these components involve comparing “as new” dimensions against dimensions measured at designated periods during the equipment’s service life.
For the HTS crane scale measurements are taken at initial start-up, every three months after commissioning or definitely after a designated number of weighing processes. In this case measurements are taken every three months or after accumulated weighing processes starting with 12,500 and proceeding at 12,500 cycle intervals (12,500, 25,000, 37,500…etc.). This model has a 10 year service life (500,000 weighing processes) after which it should be replaced.
Additional maintenance requirements:
Start up and every 3 months or 12,500 cycles:
- A dimension check-list (see below)
- Check for wearing or cracks
- Hook safety brackets
- Tighten shackle pin and nut
Every 12 months or 50,000 cycles
The maintenance should be performed by an authorized Kern service provider available via Tovatech and includes checking for gaps or cracks using magnetic powder.
At 5 years or 250,000 cycles
Replace load-carrying parts via authorized Kern customer service.
Maximum permissible variations from “as new” are provided and range from 0% (no change) to 5% on shackle components, 5 to 10% on hooks and with a maximum permissible 10⁰ hook deflection, and 1% on anchor eyelets.
A service log is kept detailing the results of the inspections. Parts replaced are similarly recorded and both documents require names and signatures of personnel performing the activity.
Full details on maintaining crane scales are provided in the operations manual. For additional information on using these devices we invite you to check our post on crane scale safety tips. And please contact our technical experts for assistance in selecting the model that best fits your requirements.