RD 153-39.4-091-01 Appendix U. Sacrificial anodes design procedure.
Horizontal anodes configuration.
Resistance to current spreading is calculated by using the formula below: 
where:
– resistance to anode current spreading
– bond cable resistance
– pipeline input resistance
Since R value is mainly dependant on the resistance to anode current spreading valuethe formula above may be simplified into: (У8)
Resistance to magnesium anode current spreading may be calculated using the following empirical formula: : (У13)
3 crossing
= 0,45*3,14+ 0,17=1,58 Ohm
where:
А and В are numeric factors 0,45 and 0,17 respectively. таблица
crossings 1
= 0,45*9,98+ 0,17=4,66 Ohm
Bond cable resistance is calculated using the below formula:
= 0,0175*28/16=1,6 Ohm
where:
0,0175Оm*mm2/m is bond cable metal (copper) resistance;
28/16 is the bond cable length and cross section.
Thereby we are able to determine the overall resistance to current spreading:
4,66 + 1,6 =6,26 Ohm
