Rating Basic. This specification provides a basis for establishing the rating for certain hoisting equipment used in drilling and producing operations@ as follows: Maximum load Rating. Thin is a calculated maximum load rating using a prescribed design Safety factor on the minimum tensile strength or the minimum yield strength of the material used in the equipment. This load rating is not intended to fix the expected service life other than by providing a reasonable and consistent margin of safety against structural failure. WARNING: The terms safety factor or design safety factor arc Intended as design criteria and should not under any circumstances be construed as allowing in excess of the maximum load rating allowing loads in excess of the maximum load rating as established under this specifications Maximum load Bearing Rating. This is a calculated maximum load main-bearing rating for crown blocks@ traveling blocks@ and swivels. This bearing rating is intended primarily to achieve consistency of ratings@ but is also intended to provide a reasonable service life for such main bearings when used at loads within the equipment rating. This specification provides the method of rating certain hoisting equipment used in drilling and producing operations@ predicated on normal field loading in which the following conditions arc considered to exist: a. loads approaching or equal to the maximum load rating are seldom encountered. b. Shock loads are occasionally encountered: however@ they arc reduced to some extent by the resiliency of the wire line and the mast or derrick. c. The fatigue limit of the material in the tool and the effect of stress risers arc recognized as important factors in design. The fatigue limit can be reduced as a result of corrosion and/or physical damage. d. d Deterioration of components due to surface corrosion and/or wear must also be considered as affecting the capability of the tool. e. Modification of repair@ including welding. without the approval of the manufacturer@ can substantially reduce the rating of a tool. f. Low temperature effects are recognized as described in Par. 3.11. Equipment Covered. Items of drilling and production hoisting equipment covered by this specification are: 1. Crown blocks 2. Traveling blocks 3. Block-to-hook adapters 4. Connecting links 5. Connectors and link adapters 6. Drilling hooks 7. Tubing and sucker rod hooks 8. Elevator links 9. Casing@ tubing@ and drill pipe elevators 10@ Sucker rod elevators 11@ Swivel bail adapters 12@ Swivels 13 Spiders 14. Deadline tie-downs 15. Rod line weights 16. Heave compensators 17. Kelly spinners@ when used as a tension member 18. Rotary tables@ as a structural member 19. Tension members of sub-sea handling equipment 20. Rotary slips Policy. American Petroleum Institute (API J specifications are published as an aid to procurement of standardized equipment and materials. These specifications are not intended to inhibit purchasers and procedure from purchasing or producing products made to specifications other than API@ and nothing in any API specification is intended to in any way inhibit the purchase of products from companies not authorized to use the API monogram.* Nothing contained in any API specification is to be construed as granting any right@ by implication or otherwise@ for the manufacture@ sale@ or use in connection with any method@ apparatus or product covered by letters patent@ nor as insuring anyone against liability for infringement of letters patent. API specifications may be used by anyone desiring to do so. and every effort has been made by the Institute to assure the accuracy and reliability of the data contained in them. However@ the Institute makes no representation@ warranty or guarantee in connection with the publication of any API specification and hereby expressly disclaims any liability or responsibility for loss or damage resulting from their use@ for any violation of any federal@ state@ or municipal regulation with which an API specification may conflict@ or for the infringement of any patent resulting from the use of an API specification. The use of the API monogram is a warranty by the manufacturer to the purchaser that the manufacturer has obtained a license to use the monogram and. further@ that the product which bears the monogram conforms to the applicable API specification. However@ the American Petroleum Institute does not represent. warrant or guarantee that products bearing the API monogram do in fact conform to the applicable API standard or specification. *The API monogram??AP??is a registered trademark of the American Petroleum Institute.