Capacitor discharge welding (CD welding)
EXPERT has been building and developing pulse transformers for capacitor discharge welding for many years. The process is characterised by the fact that large amounts of energy can be introduced into the workpiece within a relatively short time (typically 5 ms to 100 ms). The energy for the welding process is stored on capacitor banks. By selective discharge via a matching transformer, a current pulse is generated which welds the components together. The welding process itself is a projection welding process in most applications.
Due to the high energy input, the process also enables the welding of large-format components and critical material pairings. This process is used to weld gear wheels for gearboxes in the automotive industry, for example.
Another characteristic is the optimal energy utilisation. During the welding process, only very small heat-affected zones are created in the component. The energy used is almost exclusively used to melt the material directly at the joint.
Welding currents of up to 1,000,000 A have already been achieved in systems with EXPERT transformers.
Another advantage of capacitor discharge welding is the relatively low mains load, as the capacitors act as an energy buffer and can be recharged evenly during the breaks between the welds.
The systems are mainly used in large-scale production in automated joining stations.
In this process, the matching transformer (impulse transformer) not only assumes the function of optimal energy feed into the joining process. With its properties, it also decisively influences the temporal course of the welding current (pulse shape) and thus decisively influences the welding process.
EXPERT has many years of experience in the dimensioning of pulse transformers in the high current range. Our own calculation and simulation tools enable the optimum design and adaptation of the transformer to customer-specific requirements. We are also happy to support you with our experience in optimising your welding process.
The following is a selection of realised transformers with information on energy and pulse shape. The pulse shape is simulated and refers to characteristic assumptions on machine data. For dimension sheets and further technical information, please contact us. For replacement deliveries, please consult the respective machine manufacturer.
Data sheet | Type | Pulse energy[kJ] | U1N [V] |
Secondary voltages U20 [V] | Ipeak[kA] | tpeak[ms] | t50%[ms] |
---|---|---|---|---|---|---|---|
TIM0030/0004 | X-20,0-30-2000-T | 1,2 | 2000 | 20,0 | 12 | 2,2 | 7,0 |
TIM0080/0001 | X-7,5-80-3000-T | 6 | 3000 | 7,5 | 22 | 7,0 | 23,0 |
TIM0100/0012 | X1-10,0-100-2000-TM | 5 | 2000 | 10,0 | 65 | 5,0 | 14,0 |
TIM0120/0001 | X-45,0-120-900-TM | 6 | 900 | 15,0 | 40 | 2,8 | 7,0 |
TIM0120/0001 | X-45,0-120-900-TM | 6 | 900 | 22,5 | 46 | 2,3 | 5,0 |
TIM0120/0001 | X-45,0-120-900-TM | 6 | 900 | 45,0 | 66 | 1,3 | 2,7 |
TIM0190/0001 | X-61,0-190-3200-TM/M8 | 12 | 3200 | 61,0 | 51 | 4,2 | 10,5 |
TIM0250/0001 | 10/1-10,0-250-3000-T | 20 | 3000 | 10,0 | 295 | 13,0 | 24,0 |
TIM0250/0005 | 10/2-22,0-250-3300-TM | 20 | 3300 | 11,0 | 110 | 10,0 | 26,0 |
TIM0250/0005 | 10/2-22,0-250-3300-TM | 20 | 3300 | 13,2 | 123 | 9,0 | 20,0 |
TIM0250/0005 | 10/2-22,0-250-3300-TM | 20 | 3300 | 16,5 | 141 | 7,8 | 19,0 |
TIM0250/0005 | 10/2-22,0-250-3300-TM | 20 | 3300 | 22,0 | 166 | 6,2 | 14,0 |
TIM0250/0007 | 10/2-26,4-250-3300-TM | 20 | 3300 | 13,2 | 124 | 9,0 | 24,0 |
TIM0250/0007 | 10/2-26,4-250-3300-TM | 20 | 3300 | 16,5 | 143 | 7,7 | 18,0 |
TIM0250/0007 | 10/2-26,4-250-3300-TM | 20 | 3300 | 22,0 | 168 | 6,2 | 14,0 |
TIM0250/0007 | 10/2-26,4-250-3300-TM | 20 | 3300 | 26,4 | 183 | 5,4 | 11,0 |
TIM0350/0001 | X-91,7-350-3200-TM | 6 | 3200 | 91,7 | 50 | 2,0 | 4,0 |
TIM0350/0003 | X-44,0-350-3300-TM | 25 | 3300 | 11,0 | 107 | 7,5 | 28,0 |
TIM0350/0003 | X-44,0-350-3300-TM | 25 | 3300 | 22,0 | 173 | 5,3 | 12,0 |
TIM0350/0003 | X-44,0-350-3300-TM | 25 | 3300 | 44,0 | 250 | 3,2 | 6,0 |
TIM0350/0004 | X-44,4-350-3200-TM | 38 | 3200 | 11,1 | 106 | 12,0 | 36,0 |
TIM0350/0004 | X-44,4-350-3200-TM | 38 | 3200 | 22,2 | 175 | 7,7 | 18,0 |
TIM0350/0004 | X-44,4-350-3200-TM | 38 | 3200 | 44,4 | 254 | 4,6 | 9,0 |
TIM0360/0001 | 10-25,6-360-3300-TM | 30 | 3300 | 12,8 | 142 | 8,0 | 16,0 |
TIM0360/0001 | 10-25,6-360-3300-TM | 30 | 3300 | 15,3 | 151 | 7,0 | 14,0 |
TIM0360/0001 | 10-25,6-360-3300-TM | 30 | 3300 | 19,2 | 173 | 6,0 | 12,0 |
TIM0360/0001 | 10-25,6-360-3300-TM | 30 | 3300 | 25,6 | 191 | 5,0 | 9,0 |
TIM0380/0001 | X-133,3-380-1000-T-M8Pr | 10 | 1000 | 44,4 | 36 | 4,0 | 11,0 |
TIM0380/0001 | X-133,3-380-1000-T-M8Pr | 10 | 1000 | 66,7 | 44 | 3,2 | 7,0 |
TIM0380/0001 | X-133,3-380-1000-T-M8Pr | 10 | 1000 | 133,3 | 64 | 1,8 | 3,5 |
TIM0380/0002 | X-125,0-380-1500-TM-M8Pr | 36 | 1500 | 125,5 | 106 | 4,0 | 7,5 |
TIM0380/0003 | X-59,1-380-1300-T | 13 | 1300 | 29,5 | 134 | 3,7 | 7,5 |
TIM0380/0003 | X-59,1-380-1300-T | 13 | 1300 | 39,4 | 153 | 3,0 | 6,0 |
TIM0380/0003 | X-59,1-380-1300-T | 13 | 1300 | 59,1 | 177 | 2,2 | 4,0 |
TIM0380/0004 | X-125,0-380-1500-TM-M8Pr | 36 | 1500 | 125,0 | 106 | 4,0 | 7,5 |
TIM0400/0003 | X-41,3-400-3300-TM | 40 | 3300 | 10,3 | 104 | 11,0 | 40,0 |
TIM0400/0003 | X-41,3-400-3300-TM | 40 | 3300 | 13,8 | 130 | 10,0 | 35,0 |
TIM0400/0003 | X-41,3-400-3300-TM | 40 | 3300 | 20,6 | 177 | 7,4 | 20,0 |
TIM0400/0003 | X-41,3-400-3300-TM | 40 | 3300 | 41,3 | 265 | 5,0 | 9,0 |
TIM0410/0001 | X-45,0-410-900-T | 12 | 900 | 22,5 | 114 | 5,2 | 11,0 |
TIM0410/0001 | X-45,0-410-900-T | 12 | 900 | 30,0 | 132 | 4,0 | 8,0 |
TIM0410/0001 | X-45,0-410-900-T | 12 | 900 | 45,0 | 143 | 3,8 | 5,8 |
TIM0410/0002 | X-45,0-410-900-T | 18 | 900 | 22,5 | 131 | 5,0 | 9,0 |
TIM0410/0002 | X-45,0-410-900-T | 18 | 900 | 30,0 | 151 | 3,9 | 7,5 |
TIM0410/0002 | X-45,0-410-900-T | 18 | 900 | 45,0 | 173 | 2,8 | 5,5 |
TIM0850/0001 | 10/2-61,1-850-3300-TM | 36 | 3300 | 30,6 | 214 | 5,5 | 12,0 |
TIM0850/0001 | 10/2-61,1-850-3300-TM | 36 | 3300 | 36,7 | 234 | 4,9 | 10,0 |
TIM0850/0001 | 10/2-61,1-850-3300-TM | 36 | 3300 | 45,8 | 260 | 4,0 | 8,0 |
TIM0850/0001 | 10/2-61,1-850-3300-TM | 36 | 3300 | 61,1 | 295 | 3,2 | 6,5 |
TIM0860/0001 | 10/2-53,2-860-3300-TM | 36 | 3300 | 26,6 | 197 | 6,1 | 13,5 |
TIM0860/0001 | 10/2-53,2-860-3300-TM | 36 | 3300 | 31,1 | 213 | 5,5 | 11,5 |
TIM0860/0001 | 10/2-53,2-860-3300-TM | 36 | 3300 | 41,3 | 248 | 4,3 | 9,5 |
TIM0860/0001 | 10/2-53,2-860-3300-TM | 36 | 3300 | 53,2 | 279 | 3,6 | 6,5 |
TIM2000/0001 | X-68,8-2000-3300-TM | 120 | 3300 | 34,4 | 304 | 8,0 | 22,0 |
TIM2000/0001 | X-68,8-2000-3300-TM | 120 | 3300 | 41,3 | 340 | 7,0 | 16,0 |
TIM2000/0001 | X-68,8-2000-3300-TM | 120 | 3300 | 51,6 | 386 | 6,0 | 13,0 |
TIM2000/0001 | X-68,8-2000-3300-TM | 120 | 3300 | 68,8 | 451 | 5,0 | 10,0 |