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Technical Information
 
 
 
Technical Information

1. Aspects of Patinas

2. Information on the Carbono Lorena Nuances

1. Aspects of Patinas

The figures shown below demonstrate some of the typical aspects of the defects which appear in collectors. The meaning and the characteristics of different types is shown in this technical note.

Patinas

 

Color Intensity

  • (P6)P2 - P4 - P6: Normal Patinas Uniform Color, light brown (P2)to gray (P6)

Aspects of the deposits

  • P12 - Patinas striated: relatively wide bands or striations, alternately light and dark, without wear in the copper. Probable causes: excessive moisture, oil vapors, polluted atmosphere, corrosive gases or brushes in sub-load conditions.
  • P14 - Grooved Patinas such as P12, nonetheless with grooves in live copper, with a slight aspect of patina, with metal attack. Probable causes : the same as in the striated patinas , but aggravated by the longer times of operation. Nuance inappropriate for application. .
  • P16 - Stained Patinas: stained in different ways, with disorderly colors and shapes . Probable causes : deformed or dirty collector.

Spots with caused mechanically

  • P22 - Isolated or uniformly distributed spots: dark spots with attack to the edges of sheet or blades. Probable causes : Oval shaped collector ( isolated spots), lack of dynamic balance, defective bearing, misalignment of shaft (spots distributed regularly over one or many of the collector areas). .
  • P24 - Dark spots with well-defined contours, may or may not be followed by lighter spots with irregular contours. Probable causes : defect which affects a sheet or blade or a group of sheet or blades, causing the brush to rise..
  • P26 - P28 - Spots in the center of the sheet or blades P26 or at both ends P28.Probable causes : defect in the rectifier of the switch. Electrically originated spots.

Manchas de origem elétrica

  • P42 - Alternating light and dark spots. The dark sheet or blades are separated by variable number of light spots, with a polished aspect, matte o carbonized. This aspect is reproduced throughout the peripheral parts of the collector, repetitively. Probable causes : defect originated electrically, as a function of the type of armature coil, with a breakdown in switching and with a growing difficulty in the mid-sections of grooves. May be corrected by using a quality with better switching properties.
  • P46 - Equal spotting in the double polar pitch . Well or poorly defined spots, dark in color and with a matte or carbonized aspect, distant one from the other double polar pitch . Probable causes : defects in the equipotential or radial connections, or in the reel heads.

Burns

 

  • B2-B6 - Burns due to sparks in the edges of sheet or blades.
  • B8 - Burns due to sparks in the central part of sheet or blades.
  • B10 - Perforated patina . Small light spots , variable in number, spread in disorderly fashion over the entire run of the sheet or blades, with normal patina. Probable causes: sparks over the brushes or the engines with double rotation direction.

 

Spots on the collectors

Special aspects of some type of spots

  • T10 - Image of the brush. Dark or black spot reproducing the surface contact of the brush over the switch. Probable causes : prolonged breakdown of the machine without current, or a momentary stop in load.
  • T12 - Protruding sheet or blade. Dark spot due to loss of contact, resulting from the protruding blade. See L2.
  • T14 - Shrunken blades. Dark spot due to loss of contact with the blade or sheet, resulting from shrinkage . See L4.
  • T16 - Protruding Mica . Dark spots due to the fact that the mica which protrudes from the surface of the switch . Vide L6
  • T18 - Burr. Dark spots, and localized ones, due to the burr. See L8..

 

Defects in the collector sheet or blades

L2 : Protruding blade or sheet.

L4 : Shrunk blade or sheet..

L6 : Protruding Mica.

L8 : Burr in the edges.

L10 : Dragged or beaten copper.

 

Wear in the collectors

  • R2 - Normal wear. Aspect of a collector showing wear in the metal, track by track, resulting from normal wear after a long period in operation, with the correct assembly.
  • R4 - Abnormal wear. Aspect of a collector showing abnormal wear of the metal, resulting from the incorrect assembly of brushes (number of positive brushes different to number of negative brushes on the same track), or inappropriate quality, or even yet, diverse pollution.

2. Information on the Carbono Lorena Nuances

PHYSICAL CHARACTERISTICS -ELECTRICAL APPLICATIONS
GROUPS OF NUANCES NUANCES Apparent Density (g/cm³)

Resistivity
(cm)

 Hard-ness Shore C2 Rupture Flexion (Mpa) Drop in Contact (V) Friction Coefficient Current Density (A/cm²) Maximum Speed (m/s) Rate of Metal (%)
Carbographite A 176 1,60 52000 40 20 E B 8 - 10 30  
6330 1,60 15000 40 19 E E 7 30  
Graphite LFC 554 1,25 2000   10 M M 11 - 13 90  
LFC 557 1,50 1500   13 M M 6 - 10 75  
Electrographite EG 34D 1,62 1200 40 28 M M 12 50  
EG 389P 1,50 1500 30 18 M M 12 45  
EG 40P 1,60 3000 61 28 M M 12 50  
EG 98 1,59 3600 58 29 M M 12 50  
EG 98B 1,66 3650 63 30 M M 12 50  
EG 367 1,54 4300 53 20 M M 12 50  
EG 332 1,53 4650 46 18 M M 12 50  
EG 309 1,50 4200 44 22 M M 12 50  
EG 300 1,55 4200 54 25 M B/M 12 50  
EG 319P 1,48 6600 53 26 H M 12 50  
2065 1,67 1500 40 21 B B 12 30  
L 1 1,61 1300 35 22 B B 12 60  
2192 1,56 5200 55 24 E B 15 50  
AC 130 1,55 6350 70 20 E B 12 50  
Electrographite Impregnated EG 7099 1,70 1150 42 33 M M 12 45  
EG 8067 1,65 4000 70 34 M M 12 45  
AC 137 1,75 5300 85 45 E B 12 50  
CB 86 1,66 5100 65 31 E B 15 50  
Baquelite-Graphite BG 412 1,81 11000   36 E M 8 - 12 35  
BG 469 1,81 10000   36 E M 12 35  
BG 400 1,57 24000   21 E M 8 - 12 40  
BG 530 1,78 25000   27 E M 8 40  
SB 358 1,90 4100 12 18 H MB 9 35  
LFC 62 1,60 12000 30 19 E M 7 40  
Metal-graphite LFC 3 2,10 750 18 17 B B 12 45 20
CG 651 2,90 140 26 43 MB B 12 - 14 35 49
CG 50 2,70 200 22 40 MB B 12 35 50
CG 65 3,90 40 17 50 MB B 15 25 67
CG 75 4,65 10 12 48 MB B/M 16 25 77
CG 80 5,2 7 7 90 MB B 25 - 30 20 80
OMC 5,90 6 8 85 MB B 25 - 30 20 90
MC 79P 5,20 7 20 95 MB B/M 25 - 30 20 83
MC 2 5,90 40 15 145 MB B/M 30 20 91
A CLB reserves the right to alter this table without prior warning.
PHYSICAL CHARACTERISTICS - ELECTRICAL APPLICATIONS
GROUPS OF NUANCES NUANCES Apparent Density (g/cm³)

Resistivity
 (cm)

Hard-ness Shore C2 Rupture Flexion (Mpa) Drop in Contact (V) Friction Coefficient Current Density (A/cm²) Maximum Speed (m/s) Rate of Metal (%)
Eletrographite ME49 1,44 7100 40 140 E B 12,5 35 .
ME30 1,66 5080 75 351 E B 12,5 40 .
ME46 1,58 6100 70 210 E B 12,5 45 .
ME01 1,70 1520 50 246 B B 12,0 45 .
ME43 1,53 6860 70 246 E B 12,5 45 .
ME31 1,55 5080 70 210 E B 12,5 50 .
ME29 1,70 5330 80 421 E B 12,5 45 .
ME45 1,58 6350 60 420 E B 12,5 40 .
ME28 1,60 5080 65 246 E B 12,5 40 .
ME26 1,40 5840 40 196 E B 12,5 30 .
ME34 1,39 6600 40 169 E B 12,5 35 .
ME33 1,54 6100 75 316 E B 12,5 40 .
ME37 1,58 6350 75 344 E B 12,5 40 .
ME03 1,59 1270 30 176 B B 12,5 60 .
ME40 1,53 7100 55 224 E B 12,5 50 .
ME25 1,45 5840 50 232 E B 12,5 45 .
ME22 1,65 5080 50 239 E B 12,5 50 .
ME21 1,65 5080 65 480 E B 12,5 50 .
ME38 1,61 6350 65 302 E B 12,5 40 .
ME05 1,65 1540 40 211 E B 11,0 30 .
ME20 1,58 5580 60 295 E B 12,5 40 .
ME17 1,77 2030 50 351 B B 12,5 20 .
Carbon-graphite MC58 1,22 2540 12 155 M B 12,5 91 .
MC52 1,64 3050 50 281 M M 8,0 23 .
Baquelite-graphite MB61 1,94 3810 10