Safety Spotlight
By Todd Razor
Mastering Hoist Inspection Basics
Tips for Equipment Maintenance
24
Periodic inspections of planetary hoists, for the mechanical lifting of loads and personnel using a crane, must align with industry standards, adhere to manufacturer guidelines and be performed at proper intervals to ensure reliability and safety.
Ensuring safety and optimal machine performance requires regular inspections— ranging from daily and quarterly routines to annual checks and teardowns— both before placing a crane hoist into service and throughout its extended operation.
Taking shortcuts with inspection guidelines or putting off maintenance threatens to degrade operational capabilities, but it can also expose human life to greater risk.
Here are some key considerations for planetary hoist inspections that prioritize safety and machine performance:
Daily Inspection
Oil Level
A daily pre-use check should be performed for external oil leaks, repairing as necessary. Lubricant should be kept within the range indicated, ideally midway up the sight glass or at the base of the level plug port, depending on the equipment.
For hoist models with a sight glass, ensure it is clear and functional, then visually check the oil level daily. In a hoist with no sight glass, the oil level should be inspected monthly if no external leaks are detected.
Breather Valve
Located in the drum support on planetary hoists, the vent plug— also referred to as a breather valve or internal check valve— allows trapped gases inside the hoist to escape and should be inspected daily.
If there is visible damage or the vent plug does not appear to be working properly, replace the entire part. If oil is seen dripping from the vent plug, take the hoist out of service immediately and investigate the root cause.
Never paint over the vent plug or replace it with a grease fitting as this could cause air to be trapped in the drum, potentially causing drum seal leaks.
The Once Over
The daily inspection should also include visually looking at the hoist in its entirety for corroded, loose or missing bolts, pins or other fasteners, which should be tightened, repaired or replaced as necessary.
Check the hoist and drum, rotation indicator transmitters, anti-two-blocking switches and any other applicable safety equipment. Carefully inspect hydraulic hoses and fittings for chaffing, deterioration or corrosion, repairing or replacing them as needed.
If the hoist is equipped with a ratchet and pawl mechanism, inspect for proper operation and full, spring-force engagement of the pawl with the ratchet wheel.
Just Warming Up
A hoist warm-up procedure is recommended at each start. Run the crane at its lowest recommended revolutions per minute with the hydraulic hoist control valve in neutral for a sufficient time to warm up the system. This is essential at ambient temperatures below 40 degrees Fahrenheit( 4 degrees Celsius).
The hoist should then be operated at low speeds— forward and reverse— several times to prime all lines with warm hydraulic oil and to circulate gear oil through the planetary gear sets before being put to use.
Quarterly Inspection
Brake Check
Hydraulic planetary hoists are outfitted with a sprag clutch design. The spring-applied, hydraulically released, multiple-disc brake assemblies housed within the hoist enable controlled lifting.
This system permits rotation in the
Optional sight glass for an easy visual check to ensure oil level is properly maintained.
Critical brake system components such as friction discs are inspected and often replaced.
Proper installation and periodic testing of the sprag clutch prevent unintended lowering of loads.
February 2025 • www. cranehotline. com