⚙️ Thread Comb Machine

CGK-32 / CGK-75 CNC Electrode Double Thread Comb Processing Machine

A full CNC machine that combs internal taper threads on both ends of a graphite electrode body in one setup. Two model sizes cover Φ300–Φ900 mm diameters and up to 3370 mm lengths, holding single-thread pitch error within ±0.01 mm.

Request a Quote Technical Specs ↓

Φ300–Φ900 mm

Electrode Diameter

±0.01 mm

Single Pitch Error

11–15 kW

Main Motor

26–35 t

Machine Weight

Both Ends Threaded in One Setup

The CGK-32 and CGK-75 cut the internal taper threads on both ends of a graphite electrode body from a single datum.

CGK-32 / CGK-75 CNC electrode double thread comb processing machine in a production plant

The threads on both ends of a graphite electrode body must be coaxial and pitch-matched so the electrode sections join into a stable furnace column. The CGK-32 / CGK-75 is a full CNC double thread comb processing machine that machines both internal taper threads in one clamping. A purpose-built six-axis CNC control, precision AC servo drives and a heavy machine structure generate thread pitch, taper and diameter directly by CNC interpolation, with no mechanical transmission-chain error. During cutting the workpiece remains stationary while the spindle rotates slowly in coordinated X/Z motion, preserving accuracy over long production runs.

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Key Features & Working Principle

Six capabilities that deliver furnace-grade thread accuracy on both electrode ends.

1️⃣

Double-End Thread Combing

Both internal taper threads are cut in one clamping so the two ends share the same axis and pitch reference, eliminating repositioning error.

2️⃣

Six-Axis CNC Control

A purpose-built six-axis CNC system interpolates pitch, taper and diameter directly, removing mechanical transmission-chain error from the thread form.

3️⃣

Stationary Workpiece, Linked Tool Motion

The electrode body does not move during cutting. The spindle rotates slowly while the X and Z axes move in linkage, maintaining long-term accuracy.

4️⃣

High-Speed Comb Drive

The comb tool is driven by a dedicated high-speed spindle that reaches up to 1500 rpm, giving clean thread flanks in abrasive graphite.

5️⃣

CNC End-Face Scraping

The end face is scraped under CNC control to ensure perpendicularity with the thread axis and the controlled concave profile required for joint seating.

6️⃣

Z-Axis Floating Positioning

The Z-axis floating reference system delivers high positioning accuracy and compensates for blank-length variation between electrodes.

Why Choose the CGK-32 / CGK-75

Against separate threading operations or mechanical comb machines, the CGK-32 / CGK-75 wins on joint accuracy, repeatability and throughput.

🎯

Matched End Geometry

Both threads are cut from the same datum, giving coaxial ends and consistent pitch — the core requirement for a low-resistance furnace joint.

🏆

Micron-Level Thread Accuracy

Single-thread pitch error within ±0.01 mm and cumulative pitch error within ±0.02 mm per 150 mm control joint contact and current capacity.

⚙️

Wide Electrode Coverage

Two models span Φ300–Φ900 mm and up to 3370 mm in length, covering most RP, HP and UHP electrode body sizes.

📐

Long-Term Accuracy Stability

The stationary workpiece and linked tool motion protect geometry over long production runs with minimal accuracy drift.

🛡️

Heavy, Rigid Bed

Machine weights of 26 t (CGK-32) and 35 t (CGK-75) absorb combing forces and damp vibration in hard graphite grades.

💰

Line-Ready Standalone Cell

The machine works as a standalone cell and also fits as core threading equipment in automatic electrode-body processing lines.

CGK-32 / CGK-75 — Technical Data

Main technical performance indicators from the factory datasheet.

Parameter	Unit	CGK-32	CGK-75
Model	—	CGK-32	CGK-75
Machined electrode diameter	mm	300–800	450–900
Machined electrode length	mm	1600–3200	1600–3370
Main motor power	kW	11	15
Single-thread pitch error	mm	±0.01	±0.01
Cumulative thread pitch error	mm	±0.02/150	±0.02/150
Thread axis-to-end-face perpendicularity	mm	≤0.03	≤0.03
End-face flatness	mm	≤0.03	≤0.03
Thread half-angle error	′	±10	±10
Thread-hole effective diameter error	mm	0~+0.08	0~+0.08
Thread-hole taper error	″	±20	±20
Thread-hole ovality	mm	≤0.07	≤0.07
Machine weight	t	26	35

Materials & Industries Served

Designed for carbon plants machining the internal taper threads on both ends of graphite electrode bodies.

🔩

Graphite Electrode Body Threading

Φ300–Φ900 · 1600–3370 mm

⚡

UHP / HP / RP Electrodes

High-current furnace connections

🏭

Electrode Manufacturing Plants

Body + nipple matched-set output

🔗

Electrode-Body Processing Lines

Core double-threading station

🔥

Electric Arc Furnace Steelmaking

EAF · Ladle furnace electrodes

🔄

Mixed-Spec Body Production

CGK-32 / CGK-75 program selection

Frequently Asked Questions

What does a double thread comb processing machine do?

It cuts the internal taper threads on both ends of a graphite electrode body in one clamping. The CGK-32 / CGK-75 ensures the two threads are coaxial and pitch-matched so electrode sections join cleanly in a furnace column.

What electrode sizes can the CGK-32 and CGK-75 process?

The CGK-32 processes electrode bodies from Φ300 mm to Φ800 mm in diameter and 1600 mm to 3200 mm in length. The CGK-75 processes diameters from Φ450 mm to Φ900 mm and lengths from 1600 mm to 3370 mm.

What thread accuracy does the machine achieve?

Both models hold single-thread pitch error within ±0.01 mm, cumulative pitch error within ±0.02 mm per 150 mm, thread axis-to-end-face perpendicularity within 0.03 mm, thread half-angle error within ±10 arcminutes, and thread-hole taper error within ±20 arcseconds. These tolerances control joint contact area and current-carrying capacity.

How does the machine keep both threads coaxial?

The electrode body remains clamped in place while the spindle and comb tool move in coordinated X/Z linkage to cut each thread from the same part datum. Because the workpiece is not repositioned, the two threads remain coaxial and pitch-matched.

What control system does the CGK-32 / CGK-75 use?

All motion axes are controlled by a purpose-built six-axis CNC system with precision AC servo drives. Stored part programs generate pitch, taper and diameter directly through CNC interpolation, eliminating mechanical transmission-chain error.

What information is needed for a quotation?

Send us your electrode diameter and length range, thread standard and taper ratio, pitch, electrode grade, daily production target, and whether the machine will run standalone or in an automatic processing line. Include power supply, foundation and workshop layout details — our engineering team will recommend the CGK-32 or CGK-75 configuration and prepare a quotation.

Configure a CGK-32 / CGK-75 for Your Electrode Body Production

Send us your electrode diameter and length range, thread standard, taper ratio, pitch, electrode grade, daily throughput target, and whether the machine will run standalone or in an automatic processing line. Include power supply, foundation and workshop layout details — our engineering team will recommend the CGK-32 or CGK-75 configuration and prepare a quotation.