Complete E Coating Line Integrating Paint Circulation Rinsing and Electrophoretic Deposition for Metal Surface Protection

CHG designs and supplies electrophoretic coating production lines (KTL / CED / E-coating) for automotive components and other conductive metal products requiring reliable corrosion protection.

The system uses an electrically controlled immersion process to deposit a protective coating onto prepared metal surfaces. Compared with conventional spray application, electrophoretic deposition can provide effective coverage of many recessed areas and complex geometries, making it suitable for industrial components with demanding surface protection requirements.

Our engineering solutions integrate chemical pretreatment, electrophoretic deposition, paint circulation, ultrafiltration, rinsing, curing, material handling, and process controls.

Each production line is developed according to the customer's workpiece dimensions, required coating performance, production capacity, and factory conditions.

One of CHG's project applications involves an electrophoretic coating system developed for automotive battery enclosure manufacturing.

Battery enclosures often feature welded structures, internal corners, reinforcing sections, and other complex geometries. These characteristics require careful consideration during coating equipment design.

For this application, the production line was engineered around the customer's product specifications, factory layout, and required manufacturing output.

The project involved customized engineering, equipment manufacturing, overseas installation support, commissioning, and operator training.

During the initial design stage, the project team evaluated the customer's technical requirements and available workshop conditions.

The engineering process included:

• Review of battery enclosure dimensions and production requirements

• Assessment of coating process specifications

• Equipment sizing and arrangement

• Development of CAD layouts

• Coordination of material handling and processing stages

• Review of maintenance access and operating space

• Technical drawing revisions and final design confirmation

The equipment layout was refined according to the customer's manufacturing requirements before production began.

Following approval of the technical design, equipment manufacturing proceeded according to the agreed drawings and specifications.

Quality control activities were incorporated during fabrication and assembly to verify relevant equipment dimensions, construction quality, and conformity with the approved design.

Manufacturing progress was communicated to the customer throughout the project to support coordination and preparation for installation.

After equipment delivery, CHG provided technical support for installation and commissioning at the customer's facility.

The implementation covered equipment assembly, system adjustments, process testing, and preparation for production operation.

For this referenced project, the installation and commissioning phase was completed within approximately six months.

The actual implementation period for other projects depends on equipment scope, site readiness, installation conditions, and commissioning requirements.

Technical training was provided to help the customer's personnel operate and maintain the production line.

The training included:

• Equipment startup and shutdown procedures

• Production line operation

• Process parameter adjustment

• Routine inspection and maintenance

• Fault identification

• Troubleshooting procedures

• Safe equipment operation

The objective was to support a smooth transition from commissioning to regular production.

A complete electrophoretic coating line can be arranged as follows:

Loading → Degreasing → Water Rinsing → Chemical Pretreatment → Final Rinsing → KTL Deposition → Ultrafiltration Rinsing → Final Rinsing → Thermal Curing → Cooling → Inspection → Unloading

The exact number of treatment stages and process conditions are selected according to the substrate, coating material, and required performance.

Before electrophoretic deposition, metal components are cleaned to remove oils, grease, dust, and fabrication residues.

Cleaning prepares the substrate for subsequent chemical treatment and helps reduce coating defects.

The cleaning process is selected according to the workpiece material and surface condition.

After cleaning, the workpieces receive suitable chemical surface treatment.

Depending on the substrate and coating specification, the process may include rinsing, surface conditioning, and conversion coating.

Steel components may use phosphate or alternative conversion treatment systems. Aluminum and galvanized substrates require compatible chemical processes.

The pretreatment method is determined according to the coating performance requirements and the materials being processed.

Prepared workpieces enter the E-coating tank.

During cathodic electrodeposition, the workpiece acts as the cathode, and the applied electrical field causes coating material to deposit onto its conductive surfaces.

Important process parameters include:

• Applied voltage and current

• Deposition time

• Bath temperature

• Paint solids content

• Bath pH

• Conductivity

• Workpiece geometry

• Coating formulation

These parameters are controlled according to the selected paint system and required film thickness.

Following deposition, the coated components pass through rinsing stages to remove excess coating material.

An ultrafiltration system can recover paint components and provide permeate for rinsing.

This arrangement helps manage paint consumption and maintain suitable coating bath conditions.

After rinsing, the coated workpieces enter the curing oven.

Controlled heating develops the final coating properties through the curing reactions specified by the paint manufacturer.

Oven design considers workpiece mass, metal thickness, required metal temperature, production capacity, and conveyor arrangement.

Following curing, the components are cooled before handling.

Finished products are inspected according to the customer's quality standards.

Typical inspection items include dry film thickness, coating appearance, adhesion, curing performance, and corrosion resistance.

The final equipment configuration is determined according to the required coating process and factory layout.

Electrophoretic deposition can provide coating coverage on many recessed surfaces and difficult-to-access areas.

The actual coverage depends on the workpiece geometry, bath characteristics, electrical conditions, and process design.

When combined with suitable pretreatment and curing, KTL coating provides a protective film that can help improve the corrosion resistance of metal components.

Performance depends on the coating formulation, substrate, film thickness, and operating environment.

The coating process can be integrated with automated workpiece transportation and controlled deposition parameters.

This supports repeatable operation in industrial manufacturing environments.

Unlike spray coating, electrophoretic deposition does not generate conventional spray overspray.

Ultrafiltration and rinsing equipment can recover coating material, helping reduce paint losses.

Most industrial E-coating systems use water-based paint formulations.

These generally have lower solvent emissions than many conventional solvent-based coating processes, although appropriate ventilation, wastewater treatment, and chemical handling remain necessary.

Control systems can monitor operating conditions such as bath temperature, voltage, current, and other relevant process parameters.

These functions help operators maintain stable coating conditions and identify deviations requiring adjustment.

KTL coating is commonly used for conductive metal components, including suitable carbon steel, galvanized steel, and aluminum parts.

Substrate compatibility must be confirmed with the selected coating chemistry and pretreatment process.

Typical applications include:

• Automotive battery enclosures

• Vehicle structural components

• Metal brackets and supports

• Automotive chassis parts

• Industrial machinery components

• Electrical enclosures

• Fabricated steel assemblies

• Other conductive metal products requiring corrosion protection

Different applications may require different coating formulations, pretreatment systems, and quality testing procedures.

A stable E-coating process requires appropriate monitoring of bath chemistry, deposition conditions, and curing performance.

Depending on the selected coating system, the production line can incorporate monitoring of:

• Bath temperature

• pH

• Conductivity

• Paint solids content

• Applied voltage and current

• Deposition time

• Circulation and filtration conditions

• Ultrafiltration operation

• Curing oven temperature

Finished coating properties are verified through appropriate inspection and testing procedures.

These may include film thickness measurement, adhesion testing, appearance assessment, and corrosion resistance testing according to the applicable specifications.

CHG develops electrophoretic coating equipment according to the customer's actual manufacturing requirements.

To prepare a preliminary design and quotation, please provide:

• Workpiece drawings or photographs

• Substrate material

• Maximum dimensions and weight

• Required production capacity

• Coating type and film thickness

• Corrosion resistance requirements

• Pretreatment specifications

• Selected paint supplier or coating technical data

• Available workshop dimensions

• Factory clear height

• Heating energy and electrical supply

• Water and compressed air availability

• Required automation level

• Applicable quality standards

Based on this information, CHG can develop a technical proposal covering the pretreatment system, KTL coating tank, paint circulation and filtration, ultrafiltration equipment, conveyor arrangement, curing system, electrical controls, and overall production line layout.

CHG provides customized electrophoretic coating production lines for automotive and industrial manufacturers requiring integrated corrosion protection systems.

Our project scope can cover engineering design, equipment manufacturing, overseas installation coordination, commissioning support, and technical training.

With experience in automotive battery enclosure E-coating applications, CHG can develop production line solutions based on specific workpiece characteristics, coating standards, and factory requirements.

Contact CHG with your product specifications and production requirements to receive a customized KTL electrophoretic coating line proposal and quotation.