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Overhead Lifting, Hoists and Cranes
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| H.M. Cross has been providing effective solutions to customers handling problems for many years. Our policy has been to provide the complete system to effectively handle the load, including the support structure, i.e. bridge crane, monorail, jib, gantry, or manipulator; the lifting device, i.e. hoist, trolley, balancer, servo lift, etc.; and the below the hook tool, i.e. sling, grab, vacuum tool, strong bar, etc. |
| Overhead lifting equipment has application from loads weighting as little as 20 lbs. all the way up to many tons. |
| A survey conducted a few years ago found that 85% of all lifting applications were under 200 lbs. With the new OSHA standards for lifting currently in use, we have been applying overhead equipment to assist in the lifting of considerably lighter loads. |
| Some of the manufacturers we recommend are: |
- Spanco: Workstation bridge cranes and monorails, jib and gantry cranes.
- CM: Broad spectrum of chain and wire rope hoists and accessories. We especially recommend rugged Coffing Hoists.
- J.D. Neuhaus: High quality air hoists for high cycle or hazardous area applications.
- Caldwell: A huge selection of lifting beams, tongs, grabs, vacuum lifters, special slings and special lifting devices.
- Lift All: An enormous range of web, chain, and wire rope slings.
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Selection of lifting equipment should be very application specific. Some things to consider are:
- Controlling the load is the critical thing. Some hoists have an extra mechanical brake, some don’t. What would you want, lifting a heavy load over machinery?
- How often the lifting equipment will be used is also a critical factor in selecting the hoist or crane. Simplified crane and hoist duty service classifications are as follows (normally they are separated, which doesn’t make a lot of sense to us):
| HMI Hoist Class |
Normal Work Periods for Hoist |
CMAA Crane Class |
| Hoist Duty |
Typical Areas of Application |
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Max. No. Starts/Hr |
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| H1 |
Powerhouse and Utilities, infrequent handling, Hoists used primarily to install and service heavy equipment, loads frequently approach capacity and hoist idle for long periods between use. |
7.5 min |
75 |
Class A |
Standby or Infrequent Service |
| H2 |
General machine shop fabricating, assembly, storage, and warehousing; loads and utilization randomly distributed. Total running time not over 25% of work period. |
7.5 min |
75 |
Class B |
Light Service |
| H3 |
General machine shop fabricating, assembly, storage, and warehousing; loads and utilization randomly distributed. Total running time not over 25% of work period. |
15 min |
150 |
Class C |
Moderate Service |
| H4 |
High volume handling of heavy loads, frequently near rated load in steel warehousing, machine and fabricating shops, mills, and foundries, with total running time not over 50% of the work period. Manual or automatic cycling operations of lighter loads with rated loads infrequently handled such as in heat treating and plating operations, with total running time frequently 50% of the work period. |
30 min |
300 |
Class D |
Heavy Service |
| H5 |
Bulk handling of material in combination with buckets, magnets, or other heavy attachments. Equipment often cab operated. Duty cycles approaching continuous operation are frequently necessary. user must specify exact details of operation, including weight of attachments. |
60 min |
600 |
Class E |
Severe Service |
| Class F |
Continuous Severe Service Requiring Very High Reliability |
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| We have supplied several clean room cranes. They present interesting challenges mainly determined by the class of clean room. Usually they are handling expensive things and precise positioning is often required. |
| We strongly recommend that as a first step you contact us to discuss your application. |
| Recent Project: Clean Room Bridge Cranes |
| Turnkey pair of 2-ton capacity clean room bridge cranes capable of very carefully and accurately positioning components during the assembly of an optical device on two assembly towers. This accurate positioning was obtained with hoisting speeds that ranged from .3 inches per minute to 8 feet per minute. Accurate weighing of the components during assembly was required. Since headroom was limited, we built a scale system into the hoist. We also supplied the assembly towers. We performed very accurate, certified heavy welding and finish machining, holding tight tolerances to thousands of an inch over 12’ span. The platforms are 14’ high x 19’ wide x 12’ deep and load tested to 5 tons. The cutting, welding, machining and assembly was all performed in our shop. |
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Overhead Lifting, Hoists and Cranes
