Classification method of working level M1~M8 of crane mechanism

The working level of the crane mechanism is an important parameter that characterizes the heavy workload of the crane mechanism. It is related to the busyness of the crane mechanism.

Table 1 Institutional Utilization Level

Institutional Utilization Level	Total service life (h)	Note
T0	200	Not often used
T1	400
T2	800
T3	1600
T4	3200	Frequently used leisurely
T5	6300	Use often and moderately
T6	12500	Not often busy
T7	25000	Busy use
T8	50000
T9	100000

Table 2 Mechanism load state and its nominal load spectrum coefficient

Load state	Nominal load spectrum coefficient (K m )	Note
L1-light	0.125	The mechanism often bears light loads and occasionally bears the highest loads
L2—Medium	0.25	The mechanism often bears medium loads and less bears the maximum load
L3-heavy	0.50	Mechanisms are often subjected to heavier loads and often the largest loads
L4—extra heavy	1.00	The mechanism often bears the highest loads

The work level of the organization is classified into M1～M8 level (Table 3) according to the utilization level of the organization (Table 1) and the load status of the organization (Table 2).

Table 3 Institutional work level

Load state	Nominal load spectrum coefficient (K m )	Institutional Utilization Level
		T0	T1	T2	T3	T4	T5	T6	T7	T8	T9
L1-light	0.125			M1	M3	M3	M4	M5	M6	M7	M8
L2—Medium	0.25		M1	M2	M3	M4	M5	M6	M7	M8
L3-heavy	0.50	M1	M2	M3	M4	M5	M6	M7	M8
L4—extra heavy	1.00	M2	M3	M4	M5	M6	M7	M8

Utilization level refers to the busyness of the organization’s work, and is divided into 10 levels from T0 to T9 according to the total number of hours each organization is in operation during the total design life of the organization. The total design life is defined as the total number of hours the mechanism is designed to operate. It is only used as the basis for the design of mechanism parts and cannot be regarded as the warranty period.

The load state of the mechanism indicates the degree of load on the mechanism. According to the nominal load spectrum coefficient, it is divided into four grades: light, medium, heavy and extra heavy. When the actual load change of the mechanism is known, the actual load spectrum coefficient is selected, and then the nominal load spectrum coefficient that is not less than but closest to it is selected according to Table 3, and the machine state level is obtained. When the actual load status of the mechanism is unknown, the appropriate load status level can be selected according to the content in the description column of Table 3

The working level of cranes and metal structures is different from the working level of institutions. For the same crane, due to the inconsistency of the load and the unequal time of each working mechanism, even for the same crane, the working level of different mechanisms is often inconsistent with the working level of the crane. This is in the parts of different mechanisms. Pay special attention when scrapping and updating.