Matterson M20’s - at KOMATSU plant


Matterson hoists and crabs are designed to BS.466:1984 standards which facilitates the ready selection of the most economic lifting unit from a serialised range of products based upon lifting capacity and anticipated duty of the equipment. Knowing the safe working load and range of lift required the next stage in choosing the correct hoist for any application is to establish its Group Classification for which two factors are required:


1) Average time the lifting unit will be in operation. By referring to Table A the class of Utilisation ‘T’ can be obtained against the average utilisation time.

Table A

Class of
Assumed average daily
Utilisation time (hours)
Service life
of hoist (hours)
T1 ≤ 0.25 400
T2 >0.25 and ≤ 0.5 800
T3 >0.5 and ≤ 1 1600
T4 >1 and ≤ 2 3200
T5 >2 and ≤ 4 6400
T6 >4 and ≤ 8 12500
T7 >8 and ≤ 16 25000
T8 >16 50000
T9 >16 >50000


2) Type of duty on which the uplifting unit will be employed. From Table B select the most appropriate type of duty and determine the State of Loading ‘L’.

Table B

State of Loading Type of duty
L1 Hoists subjected very rarely to their maximum load and normally to very light loads.
L2 Hoists occasionally subjected to their maximum load but normally to rather light loads.
L3 Hoists frequently subjected to their maximum load but normally loads of medium magnitude.
L4 Hoists regularly subjected to their maximum loads.


3) With the two factors from Tables A and B the British Standard Classification ‘M’ of the lifting unit can be determined from table C.

Table C

State of Loading
(Table B)
Class of Utilisation (Table A)
T1 T3 T3 T4 T5 T6 T7 T8 T9
L1 M3 M3 M3 M3 M4 M5 M6 M7 M8
L2 M3 M3 M3 M4 M5 M6 M7 M8 M8
L3 M3 M3 M4 M5 M6 M7 M8 M8 M8
L4 M3 M4 M5 M6 M7 M8 M8 M8 M8

Duty class to F.E.M. standards
Corresponding to 1.S.O. standards

Average daily operating
time in hours
≤05 ≤1 ≤2 ≤4 8 16
Class of Duty V0,25 T2 V0,5 T3 V1 T4 V3 T6 V3 T6 V4 T7
type of
1 L1 Light     1Bm M3 1Am M4 2 m M5 3 m M6
2 L2 Medium   1Bm M3 1Am M4 2 m M5 3 m M6  
3 L3 Heavy 1Bm M3 1Am M4 2 m M5 3 m M6    
4 L4 Very Heavy 1Am M4 2 m M5 3 m M6      

GROUP 1Bm M3 1Am M4 2 m M5 3 m M6
Duty factor * 25% 30% 40% 50%
No of starts per hour 150 180 240 300

* Duty Factor = load lifting time + load lowering time / lifting time + idle time + lowering time + idle time

Illustrations and specifications may be changed without notice and are intended for guidance only. Please consult us for current product details.