Consumable Consumption & Welding Time

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Calculation FormulaFor the practical welder it is important to be able to estimate the requirement for stick electrodes orother filler metals quickly, easily and accurately enough. The following pages illustrate a simplifiedmethod which is intended above all to make an initial estimate possible. An accurate calculation isnot possible using generally applicable tables as the tables would become too complicated andtherefore unmanageable.

The following approach may be used as the calculation formula:

Weight of weld without weld reinforcement

x Factor for the effect of the welding position (weld reinforcement)

x Allowance for back welding (if necessary)

= Reference value for the total weight of the weld

/ 0.01894 kg/pcs. = weight of core metal rod deposited (ø3.2/350,stub 50 mm, metal recovery 100%)

x Factor for divergent electrode dimension

x Factor for divergent metal recovery

x Factor for divergent stub length

= Reference value for the number of electrodes required

The individual lines of the calculation formula are explained in a little more detail in the followingsections and are provided with summaries in the form of tables. The method of proceeding isdemonstrated briefly at the end of the section using a practical example.

Weight of WeldThe following tables provide an overview of the weight of the weld for different welding procedureswith different types of welds. The weld shapes correspond to the specifications of the standard.Recommended diameters for rods and electrodes should only be considered as reference values.The data will be too high above all in the out-of-position welds. The weights of weld metalscorrespond as they only relate to the cross-section to be filled.

reference values for gas welding of flat-position joints (one side, without backing)

thickness edge air gap rod deposition weight of weldingpreparation diameter rate joint time

mm mm mm kg/h kg/m min/m

0.8 I 0 1.5 0.17 0.024 8.51.0 I 0 2.0 0.19 0.024 7.6

4.2. Consumable Consumption and Welding Time

4.2.1 Calculation of Electrode Consumption

Efficiency and Calculation Guide

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thickness edge air gap rod deposition weight of weldingpreparation diameter rate joint time

mm mm mm kg/h kg/m min/m1.5 I 1.5 2.0 0.25 0.042 10.02.0 I 2.0 2.0 0.25 0.048 11.53.0 I 2.5 2.5 0.36 0.074 12.34.0 I 3.0 3.2 0.70 0.17 14.55.0 I 4.0 3.2 0.74 0.265 21.56.0 V 60° 3.0 3.2 0.80 0.35 25.5

reference values for shielded manual arc welding of butt welds (without backing, flat)

thickness air gap number electrode deposition weight of welding time of layers dimension rate joint per layer


1.5 0 1 2.5/250 0.5 0.03 3.62.0 0 1 2.5/250 0.61 0.036 3.53.0 2 1 3.2/350 0.53 0.064 7.25For double-vee welds it is possible to find a usable reference value for back welding on the rootside of the weld by doubling the corresponding vee weld values of half the sheet thickness andadding the weight of the weld. Back welding on the root side of the weld is assessed with approxi-mately half the weight of the root for sheet thicknesses under 8 mm and the simple weight of theroot for thicker sheets.

reference values for shielded manual arc welding of fillet welds (one side, horizontal)

thickness number electrode deposition weight of welding time a of layers dimension rate joint per layer

mm mm kg/h kg/m min/m

3.0 1 3.2/350 1.19 0.085 4.34.0 1 5.0/450 1.75 0.145 5.05.0 1 6.0/450 2.14 0.21 5.96.0 3 4.0/450+ 1.+2.l: 1.38 1.+2.l: 0.19 1.+2.: 8.3

3.2/350 3.l: 0.88 3.l: 0.11 3.: 7.57.0 3 4.0/450 1.+2.l: 1.38 1.+2.l: 0.31 1.+2.: 13.5

3.l: 1.25 3.l: 0.11 3.: 6.88.0 3 4.0/450 1.+2.l: 1.38 1.+2.l: 0.37 1.+2.l: 16.1

3.l: 1.25 3.l: 0.18 3.l: 8.61.l: 0.29 1.l: 12.2

10.0 3 4.0/450 1.42 2.l: 0.31 2.l: 13.13.l: 0.25 3.l: 10.5

l … layer

reference values for shielded manual arc welding of flat vee-welds of plates

thickness ace/gap number electrode deposition weight of welding time of layers dimension rate joint per layer


4.0 2/1 2 r 2.5/250 r 0.43 r 0.08 r 11.2c 3.2/350 c 1.2 c 0.09 c 4.5

5.0 2/1 2 r 2.5/250 r 0.48 r 0.085 r 10.6c 4.0/450 c 1.41 c 0.105 c 4.5

6.0 2/1 3 r 2.5/250 r 0.52 r 0.08 r 9.2f,c 3.2/350 f,c 1.24 f+c 0.14 f+c 6.8

7.0 2.5/1.5 3 r 3.2/350 r 0.75 r 0.14 r 11.2f,c 4.0/450 f,c 1.38 f+c 0.22 f+c 9.2


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reference values for shielded manual arc welding of flat vee-welds of plates

thickness face/gap number of electrode deposition weight of welding timelayers dimension rate joint per layer


8.0 3/2 3 r 3.2/350 r 0.75 r 0.16 r 12.8f 4.0/450 f 1.42 f 0.13 f 5.5c 5.0/450 c 1.75 c 0.14 c 4.8

9.0 3/2 3 r 3.2/350 r 0.75 r 0.14 r 11.22f,c 5.0/450 f,c 1.88 f+c 0.37 f+c 11.8

10.0 3/2 4 r 3.2/350 r 0.75 r 0.15 r 12.03f,c 5.0/450 f,c 1.88 f+c 0.47 f+c 15.0

12.0 3.5/2 5 r 3.2/350 r 0.75 r 0.17 r 13.63f,c 5.0/450 f,c 1.93 f+c 0.74 f+c 23.0

15.0 3.5/2 5 r 3.2/350 r 0.81 r 0.15 r 11.13f,c 5.0/450 f,c 2.1 f+c 0.91 f+c 26.0

r .. root pass, f .. filler layer, c .. cap layer

For double-vee welds it is possible to find a usable reference value for back welding on the root sideof the weld by doubling the corresponding vee weld values of half the sheet thickness and addingthe weight of the weld. Back welding on the root side of the weld is assessed with approximately halfthe weight of the root for sheet thicknesses under 8 mm and the simple weight of the root for thickersheets.

Effect of the Welding PositionThe welding position has different effects on the execution of a weld. It is not possible to disregardthe welding position for calculating quantities as in affects the weld reinforcement. When estimatingtime effects are to be anticipated due to higher downtimes such as cleaning, electrode replacement,lower current intensities, etc. The following tables provide rough reference values in the form of multipliers which may be used toadapt the weight of the weld for horizontal position from the first determination.

factors for divergent welding positions - weight

PB PA PG PE PF PCvee-weld 1.0 1.0 1.0 1.1 1.15 1.15fillet weld 1.0 0.95 1.0 1.1 1.05 1.0

factors for divergent welding positions - welding time

PB PA PG PE PF PCvee-weld 1.0 1.0 1.1 1.87 1.5 1.2fillet weld 1.0 0.95 1.15 1.65 1.43 1.1

The values highlighted correspond to the reference calculation.

Proportion of Weld Metal for Back WeldsWhen deciding on a specific weld preparation one should not forget back welding if it is necessaryfor quality reasons. There are certain reference points for the consumption of filler metal and thework time required for back welding. The following list is based on practical values that were gainedfrom experience in the grooving out of weld roots without major defective parts of the weld. The additional consumption is specified as a multiplier for the weight of the weld without back wel-ding. The angle information refers to the weld preparation angle or the angle of bevel preparation forU-groove welds.


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vee-weld double-vee-weld U-groove weldthickness α α β

mm 50° 60° 90° 50° 60° 90° 8° 10° 15°6…11 1.32 1.27 1.15

11…16 1.24 1.19 1.1116…20 1.21 1.18 1.1021…30 1.18 1.14 1.08

20 1.26 1.21 1.12 1.18 1.17 1.1630 1.17 1.14 1.0840 1.15 1.12 1.07 1.10 1.09 1.0860 1.10 1.08 1.06 1.05 1.0480 1.05 1.04 1.0490 1.07 1.055

100 1.035 1.03 1.025120 1.04 1.03

Allowance for Divergent Electrode DimensionsNaturally the core metal rod deposited per electrode changes if other electrode dimensions are usedfor performing a weld, i.e. a considerably higher number of thinner electrodes will be required thanof thicker electrodes to fill the same weld volume.A stub loss of 50 mm was taken into account for the following table and this applies to all dimen-sions. The metal recovery is 100 % for all dimensions.

diameter length allowancemm mm factor

1.5 250 6,832.0 250 3,842.0 300 3,072.5 250 2,462.5 300 1,973.2 300 1,203.2 350 1,00*3.2 450 0,754.0 350 0,644.0 450 0,485.0 450 0,316.0 450 0,21

* reference for the approach used

Allowance for Divergent Metal RecoveryThe metal recovery of a stick electrode is the ratio of the weight of weld metal deposited to theweight of core rod deposited. It depends on the type of electrode (e.g. contribution of metal flux pow-der from the electrode coating), the diameter of the electrode (usually somewhat higher with largerdiameters), the welding current (increasing or decreasing slightly with the current depending on thetype of coating) and the welding position (different spatter and burn-off losses).In practical use it is sufficient to calculate using the multipliers in the following table. The tableallows for standard classification in accordance with EN and the type of coating if greater deviationsare to be reckoned with.


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code type of coating allowance acc. EN factor

1 and 2 C 1.25R, RC 1.11

RR 1.05B 1.0**

3 and 4 R 0.91B 0.87

5 and 6 RA, RR, B 0.71*7 and 8 RA, RR, B 0.56*

* With high-performance types Böhler Welding’s brand designation provides a reference to the actual metalrecovery. The multiplier should be corrected accordingly (e.g. 0.62 for FOX HL 160 Ti).

** Reference for the approach used

Allowance for Divergent Stump LossesWhen determining the number of electrodes from the required weight of weld metal, allowance mustalso be made for the electrode stubs in addition to the losses included in metal recovery. The follo-wing table shows that with regard to the electrode requirement for a specific quantity of weld metal,the varying stub losses for which the welder is responsible have a greater effect on the calculationthan variations in the metal recovery of a specific type of electrode.In the case of stub lengths allowance must be made for the fact that the welder is not always whol-ly able to influence them. For example restricted access to the weld may easily lead to stub lengthsover 80 mm. In this case the designer is responsible for ensuring good access. Out-of-position weldsalso result in longer stubs than welds in the gravity position.

diameter length allowance factor for different stub length values in mm

mm mm 40 50 60 70 80

1.5 250 0.95 1.00 1.05 1.11 1.182.0 250 0.95 1.00 1.05 1.11 1.182.0 300 0.96 1.00 1.04 1.09 1.142.5 250 0.95 1.00 1.05 1.11 1.182.5 300 0.96 1.00 1.04 1.09 1.143.2 300 0.96 1.00 1.04 1.09 1.143.2 350 0.97 1.00 1.03 1.07 1.113.2 450 0.98 1.00 1.03 1.05 1.084.0 350 0.97 1.00 1.03 1.07 1.114.0 450 0.98 1.00 1.03 1.05 1.085.0 450 0.98 1.00 1.03 1.05 1.086.0 450 0.98 1.00 1.03 1.05 1.08

Example for Calculation

A metal sheet with a thickness of 15 mm is to be joined in the horizontal-vertical position. Let theweld length be 10 m.

A vee weld with a preparation angle of 60 ° is chosen as the weld preparation. For quality assuran-ce reasons the root will be back welded. A basic stick electrode will be used (the metal recoverycode according to EN is 4). An electrode with ø 3.2 mm will be used for the root and an electrodewith ø 4.0 mm will be used for the filler and cover passes. The stub length is assumed to be 70 mm.

Efficiency and Calculation

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influencing factor calculated values

weight of weld without weld reinforcement r 0.15x10 = 1.5 kgf+c 0.91x10 = 9.1 kg

x factor for the effect of the welding position 1.15(weld reinforcement)

x allowance for back welding (if necessary) 1.19reference value for the total weight of the weld r 2.05 kg

f+c 12.45 kg/ 0.01894 kg/pcs. = weight of core metal rod 0.01894

deposited (ø3.2/350, stub 50 mm, metal recovery 100%)

x factor for divergent electrode dimension r 1.0f+c 0.48

x factor for divergent metal recovery 0.87x factor for divergent stub length r 1.07

f+c 1.05reference value for the number of electrodes r 101 Stk.required f+c 289 Stk.


ExplanationsThe weight of the weld may be taken from the table “Reference Values for Manual Metal Arc Weldingof Horizontal Vee Welds in Sheet Metal”. This table is already divided into root, filler and coverpasses for assistance. The factor for the influence of the welding position may be found in theappropriate section. The same applies to back welding of the root in which case the value is chosendepending on the thickness of the sheet, the shape of the weld and the weld preparation angle.

From this information the total weight of the weld should be determined divided into areas fordifferent electrode dimensions.

The next line produces the number of electrodes if only one electrode with ø 3.2/350 with 50 mmstub and 100 % metal recovery were to be used. As a thicker electrode is used for the filler and coverpasses, allowance must be made for the altered electrode dimension. Let the metal recovery be 115%, which would result in a factor of 1/1.15 = 0.87. The altered stub length results in differenteffects depending on the electrode length.

The number of electrodes required as a result of division and multiplication is only a reference valueto which a factor must be added for any waste due to bent, contaminated or incompletely usedelectrodes.

4.2.2 Estimation of Standard Welding Time

Actual Welding TimeReduction of the costs by reducing the actual welding time is one of the most important tasks of pro-duction monitoring. In this case the actual welding time may be estimated within certain limits.However, a second factor that has just as great a significance for reduction of the overall costs isincreasing the proportion of actual welding time in the overall time.

The approach shown here uses part of the calculation for the requirement of filler metal and thedeposition rate of the individual electrodes.

= reference values for total weight of joint in kg/ deposition rate of consumable in kg/(h*A)/ chosen amperage in Ax 60 min/h= reference values for welding time in minutes


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The deposition rate is not shown for every single brand as the divergence resulting from the diffe-rent welding conditions does not justify this level of detail. The following table presents a summaryof deposition rates for different types of coating. In the case of ranges of values the lower value ineach case should be assigned to the lower current intensity limit for this electrode.

type of stick deposition rate [kg/(h*A)]electrode ø 1.5 mm ø 2.0 mm ø 2.5 mm ø 3.2 mm ø 4.0 mm ø 5.0 mm ø 6.0 mm

medium coated (rutile)R 0.01 0.009 0.009-0.015 0.009RC 0.01 0.010-0.011 0.009 0.009thick coated (rutile)RR 0.008 0.008 0.009 0.009 0.01 0.01RC 0.009 0.009-0.0091 0.009 0.009 0.01 0.01AR 0.01-0.011 0.011 0.011 0.011 0.011RB 0.008 0.008-0.009 0.008-0.009 0.009 0.009thick coated (basic)B 0.009-0.010 0.01 0.01 0.011 0.011R(B) 0.009 0.01 0.01 0.011metal powder typeRR (160 %) 0.012 0.013 0.014 0.015RR (180 %) 0.014 0.015 0.016 0.016RR (200 %) 0.016 0.017 0.018RR (240 %) 0.02 0.021AR (120 %) 0.012-0.014 0.011 0.011

Example for Calculation

A metal sheet with a thickness of 15 mm is to be joined in the horizontal-vertical position. Let theweld length be 10 m.

A vee weld with a preparation angle of 60 ° is chosen as the weld preparation. For quality assuran-ce reasons the root will be back welded. A basic stick electrode will be used (the metal recovery codeaccording to EN is 4). An electrode with ø 3.2 mm will be used for the root and an electrode withø 4.0 mm will be used for the filler and cover passes. The stub length is assumed to be 70 mm.

Thus the example is identical to the example for estimating the electrode requirement. The electro-de is specified more particularly as BÖHLER FOX EV 50 to obtain a calculation variable.

influencing factor calculated valuesweight of weld without weld reinforcement r 0.15x10 = 1.5 kg

f+c 0.91x10 = 9.1 kgx factor for the effect of the welding position 1.15

(weld reinforcement)x allowance for back welding (if necessary) 1.19

reference value for the total weight of the r 2.05 kgweld f+c 12.45 kg

/ deposition rate of consumable in kg/(h*A) 0.010/ chosen amperage in A r 110

f+c 160x 60 min/h 60

reference values for welding time in minutes r 112 minf+c 467 min



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Duty Cycle

The proportion of actual welding time is often referred to as the “duty cycle”. This valuespecified in percent does not make any statement as an absolute variable about the efficiencyof a method of working since with high-performance procedures where it is not possible toreduce the downtimes to the same extent as the actual welding time for example, the duty cyclemay actually drop in percentage despite the total welding time being lower.

The downtimes that reduce the duty cycle may be dependent on the procedure, component,operating environment and the welder himself. The individual aspects are not dealt with ingreater detail here. In any case an accurate analysis is required to find reference points forreducing the downtimes.

For the calculation of standard times attempts have been made time and again to specifyreference values for the duty cycle. Values of this type range for example from 5 % for tackwelds in assembly to over 30 % for individual production of machine casings and 55 % forseries production of machine casings up to 70 % for series production of components in turn-over jigs. One may not overlook in this case that these figures have to be checked individuallyfor each company or have to be compared with in-house statistics since investigations ofdifferent sizes of company in different sectors showed divergences in the average duty cyclebetween 30 and 75 %.

With statistically well-covered duty cycle values the standard time is calculated as follows:

Standard time = actual welding time / duty cycle x 100


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5 Comparison Table for Hardness

Rm Tensile Strength in N/mm2

HV Vickers-HardnessHB Brinell-HardnessHRC Rockwell-C-Hardness

Rm HV HB HRC

200 63 60 --210 65 62 --220 69 66 --225 70 67 --230 72 68 --240 75 71 --250 79 75 --255 80 76 --260 82 78 --270 85 81 --280 88 84 --285 90 86 --290 91 87 --300 94 89 --305 95 90 --310 97 92 --320 100 95 --330 103 98 --335 105 100 --340 107 102 --350 110 105 --360 113 107 --370 115 109 --380 119 113 --385 120 114 --390 122 116 --400 125 119 --410 128 122 --415 130 124 --420 132 125 --430 135 128 --440 138 131 --450 140 133 --460 143 136 --465 145 138 --470 147 140 --480 150 143 --490 153 145 --495 155 147 --500 157 149 --510 160 152 --520 163 155 --530 165 157 --540 168 160 --

Rm HV HB HRC

545 170 162 --550 172 163 --560 175 166 --570 178 169 --575 180 171 --580 181 172 --590 184 175 --595 185 176 --600 187 178 --610 190 181 --620 193 184 --625 195 185 --630 197 187 --640 200 190 --650 203 193 --660 205 195 --670 208 198 --675 210 199 --680 212 201 --690 215 204 --700 219 208 --705 220 209 --710 222 211 --720 225 214 --730 228 216 --740 230 219 --750 233 221 --755 235 223 --760 237 225 --770 240 228 --780 243 231 21785 245 233790 247 235800 250 238 22810 253 240820 255 242 23830 258 245835 260 247 24840 262 249850 265 252860 268 255 25865 270 257870 272 258 26880 275 261

Rm HV HB HRC

890 278 264900 280 266 27910 283 269915 285 271920 287 273 28930 290 276940 293 278 29950 295 280960 299 284965 300 285970 302 287 30980 305 290990 308 293995 310 295 311000 311 2961010 314 2991020 317 301 321030 320 3041040 323 3071050 327 311 331060 330 3141070 333 3161080 336 319 341090 339 3221095 340 3231100 342 3251110 345 328 351120 349 3321125 350 3331130 352 3341140 355 337 361150 358 3401155 360 3421160 361 3431170 364 346 371180 367 3491190 370 3521200 373 354 381210 376 3571220 380 3611230 382 363 391240 385 3661250 388 3691255 390 371

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