Engineering Services

Rocking Test Procedure prev | next

For the Rocking Test Procedure, we provide the following services to determine “Bearing Permissible Wear.”

To assess the condition of the bearing, ABS/API procedures recommend that you first determine the initial clearance or normal wear rate first. The Bearing Wear can be measured based upon the “Tilting Clearance Method.”

Tilting Clearance Measurement (Initial or the normal):

  • In each case, the measurement is performed while the crane is in operation. Two cases are listed out from the load chart based upon the critical overturning moment observed.
  • Obtain the average value (Base Value) by subsequent repeat measurements. The measuring points should be marked around the circumference, as shown in the picture below.
  • The table below outlines the method for carrying out the test and capturing the values. The test determines if the average test values, as listed in the table, exceed the acceptable wear values.dial-gauge-mounting


The Permissible Bearing Clearance is recorded using the following format:


Note: NPCC only offers the Periodical Survey Procedure as an option for cranes built by our company. This procedure helps the crane owner to renew or update Cargo Certification after a certain period of time. The crane owner is responsible for the physical experimental test; NPCC provides customized procedures, according to varying load bearing technical parameters.