1、BRITISH STANDARD MARINE SERIES BS MA 48:1976 Code of practice for Design and operation of ships derrick rigs UDC629.12.011.51:621.873.134BSMA48:1976 This BritishStandard, having been prepared under the directionof the Mechanical Engineering and the Shipbuildingand Marine Standards Committees, was pu
2、blished under the authority ofthe Executive Board on 30September1976 BSI02-2000 First published as BS1700 January1951 First revision as BS1700 May1963 First published as BS MA48 September1976 The following BSI references relate to the work on this standard: Committee reference MEE/64 andMEE/64/1 Dra
3、ft for comment72/34748DC ISBN 0 580 09182 1 Amendments issued since publication Amd. No. Date of issue CommentsBSMA48:1976 BSI 02-2000 i Contents Page Foreword ii 1 Scope 1 2 References 1 3 Definitions 1 4 Nomenclature 1 5 Coefficients for estimating rope tensions 1 6 Methods of calculating loads in
4、 derrick rigs 9 7 Methods of calculating loads in union purchase rig 15 8 Safe working loads of slewing guy units for swinging derricks 26 9 Single sheave blocks: marking of safe working load and use in the derrick rig 27 10 Care and maintenance of ships cargo blocks 29 11 Notes on derrick testing 2
5、9 12 Extract from Schedule to the Docks Regulations,1934 30 Appendix A Proof load in relation to safe working load (applicable to blocks, shackles and loose gear) 31 Appendix B Wire ropes and minimum diameter of sheaves 31 Appendix C Methods of calculating coefficients for estimating rope tensions i
6、n terms of load P 33 Figure 1 Ships derrick rigged with single span (span with winch end whip) 2 Figure 2 Ships derrick rigged with single span (span with winch end tackle) 2 Figure 3 Gun tackle rig 2 Figure 4 Ships derrick with derrick topping winch 3 Figure 5 Ships derrick rigged with span tackle
7、4 Figure 6 Ships derrick with cargo runner led parallel to span tackle 5 Figure 7 Names of cargo block head fittings 6 Figure 8 Key diagram to Table 1 and Table 2 7 Figure 9 Method of estimating resultant loads when rigged with a single part in the cargo runner and span tackle 11 Figure 10 Method of
8、 estimating resultant loads when rigged with two parts in the cargo purchase and span tackle 12 Figure 11 Method of estimating resultant loads when rigged with four parts in the cargo purchase and span tackle 13 Figure 12 Method of estimating resultant loads when rigged with the cargo runner leading
9、 parallel to the span tackle, and with seven parts in the cargo purchase and span tackle 14 Figure 13 Typical union purchase rig 15 Figure 14 Curve showing positions of cargo load when the included angle between runners is120 16 Figure 15 Diagram showing cargo load position producing maximum loading
10、, and the corresponding limiting headroom 16 Figure 16 Diagram showing additional calculations required if the included angle between runners is less than90 16 Figure 17 Positions of booms producing maximum forces if rig is to operate on the basis of maximum included runner angle 17BSMA48:1976 ii BS
11、I 02-2000 Page Figure 18 Positions of booms producing maximum forces if rig is to operate on the basis of maximum constant headroom to triangle plate 17 Figure 19 Typical values of runner tensions 17 Figure 20 Diagram showing information required 18 Figure 21 Projected plan of rig 18 Figure 22 True
12、side elevation of mast and boom 18 Figure 23 Parallelogram of forces for runners 19 Figure 24 Horizontal forces at boom head 20 Figure 25 Inclination of guy 20 Figure 26 Triangles of forces for guys 20 Figure 27 Span pull and boom thrust (inboard boom) 20 Figure 28 Form of diagram when boom is in da
13、nger of jack-knifing 21 Figure 29 Span pull and boom thrust (outboard boom) 21 Figure 30 Typical layout of load diagrams, with the order of procedure numbered1 to9 22 Figure 31 Example of the effect on guy tension of varying the position of the eye plate 23 Figure 32 Effect of headroom on the tensio
14、ns of the runners 25 Figure 33 Standing guys in unfavourable positions 26 Figure 34 Standing guys in favourable positions 26 Figure 35 Modes of rigging single sheave blocks 28 Figure 36 Key diagram to Table 15 to Table 16 34 Table 1 Rope tensions in terms of P, applicable to blocks having sheaves wi
15、th bushed plain bearings 8 Table 2 Rope tensions in terms of P, applicable to blocks having sheaves with ball or roller bearings 8 Table 3 Resultant loads on purchase blocks when rigged with the hauling part at P 2 9 Table 4 Resultant loads on purchase blocks when rigged with the hauling part at P 1
16、 9 Table 5 Approximate mass of cargo purchases of 20metres total lift 10 Table 6 Approximate mass of tubular steel derrick booms 10 Table 7 Recommended minimum safe working loads of slewing guy units for swinging derricks 27 Table 8 Breaking loads and masses of6 19 construction (12/6/1) fibre main c
17、ore 32 Table 9 Breaking loads and masses of6 24 construction(15/9/fibre) fibre main core 32 Table 10 Breaking loads and masses of6 37 construction(18/12/6/1) fibre main core 32 Table 11 Breaking loads and masses of equal lay6 26,6 31,6 41series, fibre core 32 Table 12 Breaking loads and masses of eq
18、ual lay6 26,6 31,6 36 and6 41 series, independent wire rope core 32 Table 13 Equivalents of rope sizes 33 Table 14 Minimum diameter of sheaves 33 Table 15 Rope tensions when hoisting on nine parts of rope 34 Table 16 Rope tensions when lowering on nine parts of rope 35BSMA48:1976 BSI 02-2000 iii For
19、eword This BritishStandard code of practice on ships derrick rigs is intended to serve as a guide for the use of ships officers, stevedores, designers and others connected with the working of cargo, and is a revision of BS1700:1963. In this revision, metric units have been used throughout and the wi
20、re rope tables in Appendix B have been brought into line with the recently published metric standards for wire ropes. The diameters of block sheaves are now specified in relation to the diameter at the bottom of the rope groove. Throughout this standard the forces, e.g.P, P 1 ,etc., are those result
21、ing from the application of a load W. The blocks and other items of equipment are rated in tonnes and therefore, for practical convenience, forces are expressed in tonnes instead of force units 1) . Clause4 gives standard nomenclature, and illustrates the various forms of rig, covering the ordinary
22、cargo derrick and the conventional type of heavy-lift derrick. Typical head fittings of blocks are also included. Clause5 provides a method of estimating rope tensions. Frictional resistance is an important factor in the determination of rope tensions, and the coefficients given in Table 1 and Table
23、 2 cover, respectively, sheaves with bushed plain bearings, and those with ball or roller bearings. In clause6, typical load diagrams are given for the purpose of estimating the resultant loads on blocks and shackles. Clause7 deals with the special case of a union purchase rig and describes a method
24、 of estimating the loading on the various components in the rig. In view of the many variables, a graphical method of calculation offers the most practical solution. The marking of the safe working load in union purchase, generally designated as s.w.l.(u) is optional. Clause8 gives the recommended s
25、afe working loads of slewing guys for swinging derricks, dealing with the normal case having the guys attached to the derrick head and also the case where the guys are attached to the load, which is applicable to some heavy-lift derricks and to mammoth derricks. Clause9 is applicable to the single s
26、heave block and illustrates how the various positions in the rig affect its safe working load “as rigged”. It also deals with the question of marking the safe working load in accordance with the requirements of the Docks Regulations. Clause10 includes information on the care and maintenance of cargo
27、 blocks. Cargo blocks should be periodically overhauled, and when not in use they should be carefully stowed and protected against exposure to weather so far as is practicable; they should also be lubricated. Neglect of adequate lubrication seriously increases friction in the blocks and can lead to
28、rapid pin wear. Clause11 is given for the benefit of those responsible for carrying out tests and examinations of ships derricks in accordance with the statutory requirements. Clause12 is an extract from Schedule to the Docks Regulations,1934. Appendix A gives the relationship between the proof load
29、 and the safe working load and applies to blocks, shackles and other components of lifting gear. Appendix B contains extracts from BS365 and BS302, to assist in the selection of suitable wire ropes. Appendix C indicates the methods used for calculating the friction coefficients in Table 1 andTable 2
30、; it has been included since other methods of calculation (which are sometimes used) will give different coefficients for a given friction percentage and, unless the method of calculation is stated, the results can be somewhat misleading. 1) 1tonne/ 9 810NBSMA48:1976 iv BSI 02-2000 For information a
31、ppertaining to the design and construction of the blocks, reference should be made to BS MA47 2) . A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard d
32、oes not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi to iv, pages1to35 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in
33、the amendment table on the inside front cover. 2) In course of preparation.BSMA48:1976 BSI 02-2000 1 NOTEUsers of this BritishStandard: Marine Series should note that while observing the requirements of the standard they should at the same time ensure compliance with such statutory requirements, rul
34、es and regulations as may be applicable to the individual ship concerned. 1 Scope This BritishStandard code of practice refers to the design and operation of ships derrick rigs. It gives coefficients for estimating rope tensions, load diagrams, safe working loads, requirements for testing and for ca
35、re and maintenance. Reference is also made to union purchase rigs. 2 References This standard makes reference to the following BritishStandards. BS302, Wire ropes for cranes, excavators and general engineering purposes. BS365, Galvanized steel wire ropes for ships. BS2763, Round steel wire for ropes
36、. BS MA47, Ships cargo blocks 3) . 3 Definitions 3.1 inboard boom a derrick which is positioned over the hatchway 3.2 outboard boom a derrick which is positioned outboard, either port or starboard 3.3 headroom (or drift) the vertical distance from the top of the hatch coaming or from a permanent ere
37、ction (whichever is the higher) to the point of connection of the runners (In practice the cargo hook will reduce this headroom.) 3.4 union purchase a rig in which a pair of derricks is used in combination, the derricks being fixed and the cargo runners coupled in such a way that the load is swung f
38、rom a position vertically under one derrick to a position vertically under the other (This is sometimes known as burtoning.) 3.5 jack-knifing the self-closing of a derrick boom under load, due to the forces tending to lift it exceeding those tending to hold it down 3.6 standing guy a guy used for ho
39、lding a derrick in its required position, as in the case of a union purchase rig (Hitherto referred to as a preventer guy.) NOTEStanding guys should be looped directly around derrick booms or attached to a separate derrick head lug, and secured to the ships structure by a separate and independent an
40、chorage. 3.7 slewing guy a guy used for manoeuvring a derrick. These guys are “eased off” when the standing guys are set up in union purchase NOTESlewing guy tackles should be so placed that they exert the maximum holding force on the derrick boom (seeclause8). 3.8 journal friction the effort requir
41、ed to rotate a pulley on its axle 3.9 rope friction the effort required to bend and unbend a rope around a pulley, which is largely due to the internal friction between the individual wires and strands in the rope as they adjust themselves to the different lengths along the inner and outer curves of
42、 the bend 4 Nomenclature Figure 1 to Figure 7 show arrangements of tackle and give their names. 5 Coefficients for estimating rope tensions 5.1 Effects of friction. As the effect of frictional resistance and rope stiffness is to increase materially the tension in the rope at the winch when hoisting,
43、 it should be allowed for when determining the size of the rope and the power required for the winch. Frictional resistance in ropes and pulleys is due to the combined effect of journal friction (see3.8) and rope friction (see3.9). Because of the many factors affecting frictional resistance, calcula
44、tions cannot be made with any great degree of accuracy and, for this reason, when estimating rope tensions, the friction coefficients which are to be allowed can only reasonably be based upon an arbitrary percentage depending upon the equipment used and the method of calculation. 3) In course of pre
45、paration.BSMA48:1976 2 BSI 02-2000 Figure 1 Ships derrick rigged with single span (span with winch end whip) NOTEThe plate to which the span chain is attached is variously known as the “triangle plate” or “monkey face”. Figure 2 Ships derrick rigged with single span (span with winch end tackle) Figu
46、re 3 Gun tackle rigBSMA48:1976 BSI 02-2000 3 Figure 4 Ships derrick with derrick topping winchBSMA48:1976 4 BSI 02-2000 Figure 5 Ships derrick rigged with span tackleBSMA48:1976 BSI 02-2000 5 NOTEWhen heavy lift derricks are used, suitable and sufficient stays should be rigged to provide adequate su
47、pport to the mast, and the size of the stays and mast stresses should be determined by calculation. Figure 6 Ships derrick rigged with cargo runner led parallel to span tackleBS MA 48:1976 6 BSI 02-2000 Figure 7 Names of cargo block head fittingsBSMA48:1976 BSI 02-2000 7 5.2 Coefficients. The coeffi
48、cients in this section (seeTable 1 and Table 2 and Figure 8) have been calculated on the basis that the sum of the individual rope tensions in any purchase equals the force, P, held by that purchase (neglecting such dynamic effects as acceleration and deceleration and any increase in rope tension du
49、e to a ships list). (For method of calculation, seeAppendix C.) A different method of applying the percentages may call for a materially smaller percentage to obtain comparable results, e.g.3% per sheave accumulative, or4% per sheave by simple addition (applied to the static rope tension P/N, where N is the number of parts of rope) will give coefficients comparable to6% by the method given in Appendix C. However, the sum of
