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Carbon Brushes

MC79P Metal Carbon Brush

Part No. MC79P

Mersen MC79P high-copper metal-graphite carbon brush for earthing/grounding (subway, rail), annealing-wheel (Niehoff wire drawing) and large DC-motor positions. Low resistivity 7 µΩ·cm, rated 20 A/cm²; supplied to size per drawing with copper-braid lead.

Material	Metal graphite (copper graphite)
Dimensions	- Standard size: 40 × 40 × 50 mm (per Aobo/Made-in-China listing) - Other common sizes: 20 × 40 × 40
Application	MC79P is a Mersen high-copper metal-graphite brush used for: - Earthing / grounding brushes — subway (metro) vehicles and rail rolling stock grounding systems - Annealing wheel brushes — cable factory wire-drawing and annealing machines (e.g. **N
Current Density	20 A/cm²
Grade	Mersen MC79P

Compatible Models

- Mersen MC79P (copper graphite) — grade per CarbonPro chart and Aobo listing - Mersen family cross-references: MC12 CM1S A16 RC87 RC90 - Related metal-graphite family: CG657 CG651

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Technical Specifications

Specification	Value
Grade	Mersen MC79P (high-copper metal graphite)
Material	Metal graphite (copper graphite)
Resistivity	7 µΩ·cm (CarbonPro industrial brush chart)
Flexural Strength	98 MPa (CarbonPro chart)
Density	5.2 g/cm³ (CarbonPro chart)
Current Density	20 A/cm² (CarbonPro chart)
Max Surface Speed	Not published for grade (typical metal-graphite ≤ 30 m/s — confirm)
Hardness	Not published for grade (typical Shore 50–75 — confirm)
Standard Size	40 x 40 x 50 mm (per Aobo listing)
Other Sizes	20 x 40 x 40; 20 x 40 x 50; 16 x 25 x 50; generator variant 12 mm shaft / 50 mm length; custom per drawing
Voltage	Not rated (N/A)
Lead Type	Flexible copper braid with terminal (per drawing)
Spring	Not included (brush-holder supplied)
Family Cross-References	MC12, CM1S, A16, RC87, RC90; related CG657/CG651/CG75/OMC/CZ01
Application	Earthing/grounding (subway, rail); annealing wheel (Niehoff wire drawing); steel-plant large DC motors; generators & motors

Compatible Models

This MC79P Metal Carbon Brush is designed as a direct replacement for the following machine models and series:

- Mersen MC79P (copper graphite) — grade per CarbonPro chart and Aobo listing - Mersen family cross-references: MC12 CM1S A16 RC87 RC90 - Related metal-graphite family: CG657 CG651 CG75 OMC CZ01 (verify application fit) - Niehoff wire-drawing / annealing machines (annealing-wheel brush positions) — verify per machine - Subway (metro) / rail vehicle earthing-grounding systems — verify per vehicle type - Steel-plant heavy plate mill large DC motors (16 × 25 × 50 mm class) — verify per machine - DC generators and motors requiring a high-copper grounding brush (verify per machine)

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Description

This Mersen MC79P carbon brush is a high-copper metal-graphite (copper graphite) brush used where low resistance and high current transfer are essential: earthing/grounding brushes on subway and rail vehicles, annealing-wheel brushes on cable-factory wire-drawing and annealing machines (Niehoff), and large DC motor/generator brush positions such as steel-plant heavy plate mill drives. The high copper content delivers very low bulk resistivity (7 µΩ·cm), high density (5.2 g/cm³) and a rated current density of 20 A/cm² per the CarbonPro industrial brush chart. The brush is manufactured to your required size (standard 40 × 40 × 50 mm, or 20 × 40 × 40, 20 × 40 × 50, 16 × 25 × 50 mm and custom), with flexible copper-braid lead and terminal, ready for installation in the corresponding brush holder.

Features & benefits:

Mersen MC79P high-copper metal graphite — very low resistivity (7 µΩ·cm), high current capacity, rated 20 A/cm²
Grounding-proven — subway/rail earthing brushes and lightning-grounding service
Annealing-wheel proven — cable-factory wire-drawing machines (Niehoff) annealing-wheel positions
Large DC-motor proven — steel-plant heavy plate mill and generator brush positions
Custom to your drawing — sizes, lead length and terminal per specification
Flexible copper shunt — reliable, balanced current transfer
Quality-inspected before dispatch: dimensional check, lead crimp integrity, and surface condition per batch