According to different standards, crane service can be divided into different classifications. Usually, the most frequently used standards are ASME, CMAA, HMI, ISO, CEN EN, FEM and OSHA. In the following paragraph, it will put in length on crane service classifications based on CMAA (Crane Manufacturers Association of America), HMI (Hoist Manufacturer’s Institute), FEM (Federation Europeenne de la Manutention), and AISE Crane Service Classifications, and their comparisons for your sake to select the proper crane machine for your application.
CMAA classifies crane services into six classes: A, B, C, D, E, and F, shown in the following paragraphs:
Class A Infrequent Service
Crane comes into class A has the features:
Class B Light Service
Crane comes into class B has the features:
Class C Moderate Service
Class D Heavy Service
Crane comes into class D has the features:
Class E Severe Service
Crane comes into class E has the features:
Class F Continuous Servers Service
Crane comes into class F has the features:
According to FEM standards, crane services can be grouped in the classes of Light, Medium, Heavy, and Very Heavy.
Factors determines the crane services group based on FEM standards are:
1. Load spectrum, which presents the frequency of loads with maximum and smaller lifting capacity during examined time.
2. Number of hoisting cycles during the lifetime of crane.
Example of different load spectrums:
AISE also gives its method to calculate the crane services class, which is generally described in as follows:
Further AISE describe the different Load Classes as:
The crane services class of a crane is determined as the following diagram based on the above load classes and load cycles.
HMI also provides a method based on the relative significance of duty cycle ratings for different types of electric hoists. HMI hoist service classifications is provided in the following table:
Note: It requires various additional information of the hoist application conditions to determine the duty cycle.
Different crane service classifications are given based on different standards. In order to give you a better understanding to the different crane service classifications, the comparison on CMAA, FEM, ISO, and HMI crane service classification are shown in the following table:
Various crane service classifications based on different standards are various ways to help you to select the proper crane or hoist for you application. Do remember when choose the crane or hoist for your application, you have to consider the following factors which need to confirm with your crane or hoist manufacturer:
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