42 0 693KB
To:
From
Central Fleet Support
Jan Jaap van Tuijl
Revision: A Date 04 March 2016 Page
CALCULATION NOTE
GUIDELINES FOR THE SIZING OF CHAIN LOCKERS
1|9
INTRODUCTION This calculation note described the sizing of chain lockers. In this note the chain locker guidelines which were received from IHC, COSCO and taken from the Anchor Handling book are summarized.
GUIDELINES OF IHC The following table about sizing of chain lockers was found in the IHC yard standard. Table 1: Necessary volume [m3] for 100 [m] anchor chain
Chain diameter D [mm] 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
Chain locker volume 3 V [m ] 0.216 0.247 0.279 0.315 0.351 0.387 0.427 0.468 0.513 0.558 0.607 0.657 0.706 0.760 0.814 0.873 0.931 0.994 1.057 1.120 1.188 1.255 1.327 1.399
Chain diameter D [mm] 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62
Chain locker volume 3 V [m ] 1.476 1.552 1.629 1.710 1.746 1.876 1.962 2.052 2.142 2.232 2.326 2.425 2.524 2.623 2.722 2.826 2.998 3.042 3.150 3.262 3.375 3.492 3.609 3.726
CALCULATION NOTE GUIDELINES FOR THE SIZING OF CHAIN LOCKERS
(Continued)
Chain diameter D [mm] 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78
Chain locker volume 3 V [m ] 3.847 3.973 4.099 4.225 4.351 4.482 4.617 4.842 4.887 5.026 5.166 5.310 5.454 5.602 5.751 5.899
Chain diameter D [mm] 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95
Chain locker volume 3 V [m ] 6.052 6.205 6.363 6.520 6.678 6.840 7.006 7.173 7.339 7.510 7.681 7.852 8.028 8.208 8.388 8.568 8.752
th
In Excel a power function as well as a 4 order polynomial function was determined in order to calculate the chain locker volumes for larger chain diameters than shown in the table above. Chain locker volume function 𝑃𝑜𝑤𝑒𝑟 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 𝑉1 = 𝑐 𝑑𝑐 𝑏 Or
𝑃𝑜𝑙𝑦𝑛𝑜𝑚𝑖𝑎𝑙 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 𝑉1 = 𝑐4 𝑑𝑐 4 + 𝑐3 𝑑𝑐 3 + 𝑐2 𝑑𝑐 2 + 𝑐1 𝑑𝑐 1 + 𝑏
Whereby: V1 Effective chain locker volume dc Chain diameter
3
[m ] [mm]
Table 2: Power function coefficients
Power function
c 0.000962962
b 2.001744014
Table 3: Polynomial function coefficients
Polynomial function
Date 04 March 2016
c4 2.55346E-09
c3 -7.38665E-07
c2 0.001039204
c1 -0.002422335
b 0.025432392
Page 2|9
CALCULATION NOTE GUIDELINES FOR THE SIZING OF CHAIN LOCKERS
Other guidelines mentioned in the IHC standard are;
Between the ancherchain and the end of the spurling pipe 1.2 – 1.8 [m] needs to be available. Self stowing properties of the chainlocker are reached when, if possible, a relatively small base is used compared to the height of the locker. The width in case of a square shaped chainlocker must fullfill the requirement