Crane Application - Documented Cost Saving

Crane Application - Documented Cost Saving

Great Cost Savings for Crane Application

A customer was experiencing regular wheel bearing failure and loss of grease from the bearings in an automated crane application, within a product distribution center. The customer had to change 40 wheel hub units over a 5 year period. NSK carried out a bearing failure analysis confirming that the wheel bearings were suffering from lubrication starvation and radial pre load. A solution were to come.


To overcome this, NSK recommended the use of pre-greased NSK Sealed Double Row Angular Contact Bearings with an increased radial internal clearance of C3. A trial of 8 wheels, using the modified crane wheel assemblies with NSK bearings, was carried out with no bearing failures reported over 12 months. The solution increased productivity and reduced maintenance costs resulting in a significant cost saving of 58.176 €.

Key Facts

• Material handling and warehousing

• Frequent bearing failure resulting in customer changing 40 wheel hubs every 5 years

• Bearing failure causing significant production down time and high costs

• Lubrication starvation & particle ingress

• Radial pre load problems

• Expensive OEM parts

• NSK Solution: pre-greased Sealed Double Row Angular Contact Bearings with C3 clearance

• Productivity improvement & cost saving generated


Background Information

• Sector: Material Handling

• Country: UK

• End-product: Boxed items for general sale

• Application: Crane Application in Distribution Centre

• Number of machines: 25

• Approx. Lifetime: 1 1/2 months

• Problem: Ingress of contamination, lubrication starvation and radial pre load


Value Proposals

• NSK engineering conducted an Application Review and a Bearing Failure Analysis showing lubrication starvation and radial pre load within the original bearings causing subsequent failure and lubrication fall out

• NSK engineering reviewed the original wheel design recommending the use of a pre-greased sealed NSK Angular Contact Bearing issuing modified wheel machining drawings and a fitting procedure for correct assembly

• A trial was agreed to modify 8 crane wheels with the use of pre loaded and sealed NSK Angular Contact Bearing

• The result of the trial was an increase of bearing life, reduction of maintenance costs and increase in productivity resulting in a large cost saving


Product Features

• Seals RSR: made of nitrile rubber reinforced with an embedded steel disc

• Contact seals providing excellent protection against the ingress of contamination, reducing wear on the raceways and ball surface, reduced noise, vibration and risk of lubricant failure

• Accommodate radial and axial forces in both directions