ASME B30 21 INTERPRETATIONS-1992 Interpretations to B30 2-1994 Manually Lever Operated Hoists《B30 2-1994的说明 手动操作杆式提升机》.pdf

1、ASME B30.21-1994 Interpretations Replies to Technical Inquiries December 1989 - December 1992 FOREWORD This publication includes all of the written replies issued between the indicated dates by the Secretary, speaking for the ASME B30 Committee, Safety Standards for Cableways, Cranes, Derricks, Hois

2、ts, Hooks, Jacks, and Slings, to inquiries concerning interpretations of technical aspects of ASME B30.2 I, Manually Lever Operated Hoists. These replies are taken verbatim from the original letters except for a few typographical corrections and some minor editorial corrections made for the purpose

3、of improved clarity. In some few instances, a review of the interpretation revealed a need for corrections of a technical nature: in these cases a corrected interpretation follows immediately after the original reply. These interpretations were prepared in accordance with the accredited ASME procedu

4、res. ASME pro- cedures provide for reconsideration of these interpretations when or if additional information is available which the inquirer believes might affect the interpretation. Further, persons aggrieved by this interpretation may appeal to the cognizant ASME Committee or Subcommittee. ASME d

5、oes not “approve,” “certify.” “rate,” or “endorse” any item. construction, proprietary device, or activity. I ASME B30-23A 95 0757b70 0574344 790 m 830.21 Interpretations 21-1 Interpretation: 21-1 Subject: ASME B30.21-1989 Date Issued: December 15, 1992 Question (1): Does the Standard prohibit a lev

6、er operated hoist from being used as a sling or load binder? Reply (I): The B30.21 Standard does not specifically prohibit the use of a lever operated hoist as a sling or load binder. The requirements for the use of the hoist are stated in Section 21-0. I - Scope, and in the text, and particularly i

7、n Sections 2 I - 1.7, 2 1-2.6, and 2 I -3.6 - Operation . These requirements, in particular, and the others found in the B30.21 Volume must be met when the hoists are used as a sling or a load binder. Section 21-0.1 - Scope of B30.21 Within the generd scope defined in Section 1, B30.21 applies to ma

8、nually lever operated hoists utilizing chain (see Fig. I), wire rope (see Fig. 2), and web strap (see Fig. 3) for the purpose of lifting, pulling, and tensioning applications, comprising hoists of the following types: (a) ratchet and pawl operation (b) friction brake operation Lever operated hoists

9、of other types than those detailed in this volume shall be used only in accordance with Hoists used for lifting personnel require special considerations and are not included in this Volume. Specially insulated hoists used for handling electrically energized power lines require special considcrations

10、 and are not included in this Volume. recommendations of the hoist manufacturer. 21-1.7.2 Before Operating Hoist (k) Hoists shall not be operated by other than hand power of one operator. 21-1.7.3 Handling the Load (a) The hoist chain shall not be wrapped around the load. (g) Hoists shall not be ope

11、rated until the load block, chain, and hoist body are directly in line with the direction of loading to avoid side pull. (h) The hoist body or frame shall not bear against any object or the supporting structure. (r) The operator should not leave a loaded hoist unattended unless specific precautions

12、have been instituted and are in place. 21-2.6.2 Before Operating Hoist (k) Hoists shall not be operated by other than hand power of one operator. 21-2.6.3 Handling the Load (a) The hoist wire rope shall not be wrapped around the load. (f) Hoists shall not be operated until the load block, wire rope,

13、 and hoist body are directly in line with the direction of loading to avoid side pull. The hoist body or frame shall not bear against any object or the sup- porting structure. (g) The operator shall not apply a load beyond the rated load appearing on the hoist or load block, except during properly a

14、uthorized tests. (9) The operator should not leave a loaded hoist unattended unless specific precautions have been instituted and are in place. 21-3.6.2 Before Operating Hoist (h) Hoists shall not be operated by other than hand power of one operator Only portions of these Sections are included in th

15、e following excerpts. Refer to 830.21 Volume for the full text 3 ASME B30-23A 95 m 0759670 0574345 b27 21-1 630.21 Interpretations 21-3.6.3 Handling the Load (a) The hoist web strap shall not be wrapped around the load. (f) Hoists shall not be operated until the load block, web strap, and hoist body

16、 are directly in line with the direction of loading to avoid side pull, The hoist body or frame shall not bear against any object or the sup- porting structure. during properly authorized tests. and are in place. (8) The operator shall not apply a load beyond the rated load appearing on the hoist or

17、 load block, except (q) The operator should not leave a loaded hoist unattended unless specific precautions have been instituted Question (2): Can a chain hoist or a lever hoist be used as a sling in a two component (bridle) configuration? Reply (2): A chain hoist or a lever hoist cannot be used as

18、a sling in the sense that load supporting means of a sling (the chain, the wire rope, or the web strap) come into contact with the load. A chain hoist or a lever hoist can be used as a leg of a multiple leg sling if it is used in accordance with the following requirements in particular, and the othe

19、rs found in the B30.21 Volume. 21-1.7.2 Before Operating Hoist (k) Hoists shall not be operated by other than hand power of one operator. 21-1.7.3 Handling the Load (a) The hoist chain shall not be wrapped around the load. (b) The load shall be attached to the load hook by suitable means. 21-2.6.2 B

20、efore Operating Hoist (k) Hoists shall not be operated by other than hand power of one operator. 21-2.6.3 Handling the Load (a) The hoist wire rope shall not be wrapped around the load. (b) The load shall be attached to the load hook by suitable means. (8) The operator shall not apply a load beyond

21、the rated load appearing on the hoist or load block, except during properly authorized tests. 21-3.6.2 Before Operating Hoists (h) Hoists shall not be operated by other than hand power of one operator. 21-3.6.3 Handling the Load (a) The hoist web strap shall not be wrapped around the load. (b) The l

22、oad shall be attached to the load hook by suitable means. (g) The operator shall not apply a load beyond the rated load appearing on the hoist or load block, except during properly authorized tests. Question (3): Can a chain or lever hoist be used as a component (bridle) of the rigging described abo

23、ve if the load chain was replaced with an alloy chain? Reply (3): No. The load chain in a chain or lever hoist cannot be replaced with a sling chain. The load chain in a chain hoist is surface hardened alloy steel chain for resistance to wear while traveling around and through the hoist. Conversely,

24、 the sling chain is through hardened for strength and toughness to sustain the stresses encountered. Only portions of these Sections are included in the following excerpts. Refer to B30.21 Volume for the full text 4 630.21 Interpretations 21-1 Question (4): Does ASME plan to modify the Standard to c

25、omplement the responses to the questions proposed above in either Addenda or the general Edition? Reply (4): No. The text of the B30.21 Volume will not be modified to complement the responses to the above questions. The scope and text of the Volume define the purpose and conditions of use for a lever hoist. A lever hoist can be used as a hoist, puller, or tensioning device if the application meets the requirements of the Volume. 5