ASME Hoist Duty Classification

ASME Hoist Duty Classification

Shupper-Brickle Equipment Co12/ 1/18

What is hoist duty? The ASME Hoist Duty Classification is a rating system to make sure a hoist is suitable for the application. It’s based on a combination of how often the hoist is used and how much of its capacity is used.

Find a listing of ASME Duty Classes here and below, including service descriptions and a table of usage times.

Most hoists purchased for commercial or industrial use have an H3 or H4 duty rating. If you need an H5 rated hoist, please contact us about your application.

Read our blog post: What's the toughest duty for a hoist? See also: The Top Hoist Purchasing Mistakes to Avoid

  

ASME standards specify the Duty Class of a hoist:
 

ASME Duty Classes

 

 

Service Classification

 

 

Description

 

 

H1

 

 

Infrequent or Standby

 

 

Idle 1-6 months, used for installation and/or maintenance

 

 

H2

 

 

Light

 

 

Light maintenance, fabrication; capacity loads infrequently handled; randomly distributed loads; low running time

 

 

H3

 

 

Standard

 

 

General machining; randomly distributed loads; total running time ≤ 25% of working period

 

 

H4

 

 

Heavy

 

 

High volume handling of heavy loads near rated capacity; steel warehousing, machining, foundries; total running time ≤ 50% of working period

 

 

H5

 

 

Severe

 

 

Bulk material handling with attachments; approach continuous operation

 

 

 

Hoist Class

Hoist Bearing life at K=0.65 (hours)

Uniformly Distributed Work Periods

Infrequent Heavy Work Periods

Max. On Time Minutes Per hour

Max. No. Of Starts Per Hour

Minutes

Starts

H1

1,250

7.5

75

15

100

H2

2,500

7.5

75

15

100

H3

5,000

15

150

30

200

H4

10,000

30

300

30

300

H5

20,000

60

600

N/A

N/A