Forged Eye bolts come in many sizes, can be imperial or metric in thread sizing and are an economical way of installing lifting eyes when needed.
It is very important to use only brand name eye bolts when lifting. The eye bolt manufacturer should have their name or logo and size on each eyebolt. This is important as they should have further information on application, installation and work load limits available in print or on-line which will be very important to read before using.
For example, forged eye bolts are only allowed to pull in-plane on eye bolts and if they need to be rotated, shim sizes are provided so they are orientated in a manner that will maximize their capacities. They must be tightened firmly against the load. You lose 70% of the rated capacity when side pulling or lifting in-plane at 45 degree horizontal angle and 75% when lifting or pulling in-plane at 90 degree horizontally. These are just some of the reasons why you should understand eye bolts capacities, even those from reputable manufacturers', to ensure you are using them properly and have the right product for the right job.