Powder coating for elevator applications is a powder coating specially designed for the decoration and protection of elevator cabins, door panels, guide rails, and accessories. It needs to combine a highly decorative appearance, excellent mechanical properties, and safety and durability requirements specific to elevator applications, such as flame retardancy, wear resistance, and chemical resistance.
This article systematically introduces the concept, types, characteristics, functions, application areas, selection considerations, and common problem-solving measures of powder coating for elevator applications, with a particular focus on the applications of powder coating for elevators, to help you better understand what powder coating for elevator applications is and what functions it provides.
What Is Powder Coating for Elevator Applications
Powder coating for elevator applications is a thermosetting powder coating specially designed for coating the surfaces of elevator components. It is applied by electrostatic spraying and cured at high temperature to form a coating film. It needs to meet the comprehensive requirements of elevator applications for decoration, mechanical strength, chemical resistance, safety, and environmental performance.
Types of Powder Coating for Elevator Applications
According to the resin system, it can be classified into the following types.
- Epoxy-Polyester Hybrid Type
This is a commonly used indoor powder coating for elevator components. It combines the corrosion resistance of epoxy resin with the decorative properties of polyester resin and is suitable for indoor metal components of elevators. It has a relatively low cost and is suitable for non-visible components inside elevator cabins with conventional appearance and protection requirements.
- Pure Polyester Type
Compared with the epoxy-polyester hybrid type, it has significant advantages in weather resistance, powder deposition efficiency, yellowing resistance, decorative performance, and gloss. It is more suitable for visible elevator components with higher requirements for decorative appearance and long-term color stability. Some products use low-temperature curing formulations, such as 160°C, which can reduce energy consumption.
The polyurethane type uses a hydroxyl resin and isocyanate system, providing excellent weather resistance and chemical resistance. It is suitable for elevator components with special durability requirements.
Characteristics of Powder Coating for Elevator Applications
Powder coating for elevator applications has the following characteristics.
High Decorative Performance: The coating is smooth and even, with uniform gloss, and can provide a variety of colors and texture effects to meet the appearance requirements of visible elevator components such as elevator cabins and door panels.
Excellent Mechanical Properties: It has strong adhesion, with cross-cut adhesion typically reaching Grade 0. as well as good impact resistance and flexibility, allowing it to withstand vibration and frequent contact during elevator operation.
Wear Resistance and Slip Resistance: Considering the frequent movement of people inside elevators, some products use additives to enhance wear resistance and slip resistance.
Chemical Resistance: It can withstand repeated wiping with common cleaning agents such as acids, alkalis, and alcohol while maintaining stable appearance and performance.
Corrosion Resistance: Neutral salt spray resistance can typically exceed 500 hours, making it suitable for complex environments such as elevator shafts.
Flame Retardancy and Safety: It needs to pass flame and toxicity tests to meet fire safety requirements for elevator applications.
Environmental Performance and Energy Efficiency: As a powder coating, it contains no VOCs. Some products support low-temperature curing, such as 160°C, which reduces energy consumption.
Functions of Powder Coating for Elevator Applications
The functions of powder coating for elevator applications are as follows.
- Protective Function
(1) Oxidation and Rust Prevention: A dense coating film is formed on the surface of carbon steel components to isolate moisture and oxygen, preventing corrosion of landing doors, elevator cabins, shaft components, and other parts and extending their service life.
(2) Chemical and Cleaning Agent Resistance: It can withstand repeated wiping with common cleaning agents such as acids, alkalis, and alcohol while maintaining coating stability.
(3) Wear and Impact Resistance: It withstands vibration and frequent contact during elevator operation, reducing coating damage.
- Decorative Function
(1) Appearance Enhancement: The coating is smooth and even, with uniform gloss, and can provide a variety of colors to meet the aesthetic requirements of visible components such as elevator cabins and door panels.
(2) Compensation for Substrate Defects: Textured/artistic powder coatings can conceal surface defects such as pinholes, orange peel, and pitting on substrates such as castings.
Specific Application Areas of Powder Coating for Elevator Applications
What areas of elevators are mainly coated with powder coating? Its specific applications are as follows.
- Main Elevator Components
(1) Elevator Cabins and Door Systems: This is the core application area for powder coating. Elevator cabin wall panels, ceilings, car doors, landing doors, door frames, and landing door frames all require powder coating to prevent oxidation and rust while maintaining an attractive appearance. Elevator door panels usually require coating on both sides during spraying, placing high requirements on the coating’s leveling and hiding power.
(2) Side Panels and Metal Components: Elevator side panels, cabin walls, door frames, escalator metal accessories, and other key appearance and structural components are now widely coated using electrostatic powder coating instead of traditional liquid painting to improve corrosion and aging resistance.
- Control and Structural Components
(1) Electrical Control Cabinets: Elevator control cabinets, control stations, and other metal housings are also typical applications for powder coating. The coating is required to have good adhesion, impact resistance, and a fine surface finish.
(2) Elevator Shaft Steel Structures: For prefabricated steel-structure elevator shafts, the steel components require anti-corrosion coating. Powder coating can be used for the protective treatment of such components.
How to Choose Powder Coating for Elevator Applications
When selecting powder coating for elevator applications, we may face the problem of not knowing how to make the right choice. Based on our industry experience, we recommend focusing on the following aspects when selecting powder coating for elevator applications.
- Identify the Component Position and Determine the Selection Direction
Different elevator components have different priorities in terms of decorative and protective requirements.
(1) Visible Decorative Components (Cabin Wall Panels, Door Panels, Door Frames): Decorative performance takes priority. Focus on coating gloss uniformity, leveling, color difference control (ΔE ≤ 1.0), fingerprint resistance, and scratch resistance. If a special texture is desired, textured/artistic powder coating can be considered to conceal minor substrate irregularities.
(2) Internal/Structural Components (Shaft Components, Brackets, Counterweights): Protection takes priority. Focus on neutral salt spray performance, adhesion, and complete coverage. These components have relatively less stringent appearance requirements, but effective rust prevention must be ensured to avoid corrosion caused by coating damage.
- Refer to Standards and Identify Key Performance Indicators
Regardless of the type selected, suppliers should be required to provide test reports that comply with or exceed T/CEAC 118-2025. The key indicators can refer to the following typical requirements:
(1) Appearance and Film Thickness: The coating should be uniform and free of defects such as craters and bubbles. Film thickness is typically controlled at 60–80 μm, while textured powder may require 80–120 μm to achieve the desired effect.
(2) Adhesion: The cross-cut adhesion test should reach Grade 0. the highest grade, which is the basis for preventing coating delamination.
(3) Mechanical Properties: Impact resistance typically requires ≥50 kg·cm (forward and reverse impact), while the flexibility bending test should be ≤3 mm without cracking to withstand stresses during assembly and operation.
(4) Chemical and Corrosion Resistance: The coating should provide resistance to alcohol wiping, such as no abnormality after 50 cycles, acid and alkali resistance, such as 300 hours of acid resistance and 200 hours of alkali resistance, and neutral salt spray resistance of ≥500 hours to withstand cleaning agents and humid air in elevator environments.
(5) Curing Conditions: Confirm the recommended curing window, such as 180°C/15 min, to ensure that the workpiece reaches the actual required temperature in the oven, which is a prerequisite for achieving the required performance.
- Select the Resin System According to Requirements
(1) Pure Polyester System: Suitable for visible components with higher requirements for appearance, color stability, and weather resistance. Its leveling and yellowing resistance are generally better than those of hybrid systems, allowing elevator panels to maintain their appearance for a longer period.
(2) Epoxy-Polyester Hybrid Type: Suitable for internal structural components or areas without high requirements for long-term appearance retention. It provides balanced physical and chemical properties and good corrosion resistance with high cost-effectiveness, but is not suitable for long-term outdoor exposure or strong UV environments.
Common Problems and Solutions for Powder Coating for Elevator Applications
The most common problems encountered when using powder coating for elevator applications are mainly reflected in the following aspects. Based on our industry experience, we propose corresponding solutions to help effectively solve powder coating problems you may encounter.
- Orange Peel (Poor Leveling)
Problem: The coating surface presents an uneven texture similar to orange peel, with reduced gloss and distinctness of image (DOI). This is particularly noticeable on highly visible surfaces such as elevator door panels and cabin wall panels.
Possible Causes: This is one of the most common problems in coating processes. The root cause is usually not the powder itself, but an imbalance among film thickness, electrostatic parameters, and curing kinetics. When the film is too thick, the coating begins to gel before sufficient leveling takes place, locking the surface texture in place. Excessively high voltage can also cause uneven powder distribution, creating local peaks and valleys.
Solutions: Control the film thickness within the recommended range of 60–80 μm. Reduce the spray gun voltage, slow down the gun movement, and ensure consistent overlap. Use a temperature profiling instrument to measure the actual metal temperature of the workpiece and ensure that the coating has sufficient melting and leveling time.
- Craters
Problem: Circular depressions appear on the coating surface. In severe cases, the substrate becomes exposed, affecting both appearance and protective performance.
Possible Causes: Craters are caused by contaminants with low surface tension. Molten powder migrates outward from the contaminated area, forming depressions. Contamination sources include oil or moisture in compressed air, cross-contamination of powder caused by incomplete color changes, and residual oil or pretreatment chemicals on the workpiece surface.
Solutions: Install an oil-water separator after the air filter. Thoroughly clean the spray booth, recovery system, and powder supply lines during color changes. Check the cleaning effectiveness of the pretreatment process. For castings with micropores or sand holes in the substrate itself, preheated spraying or a two-coat process can be used to alleviate the problem.
- Pinholes
Problem: Dense small holes appear on the coating surface. They may sometimes be difficult to detect with the naked eye but can reduce gloss and protective performance.
Possible Causes: Pinholes are essentially caused by gas escaping during the curing process. There are two main sources of gas: first, low-molecular-weight volatiles generated by the powder coating itself during curing; second, moisture adsorbed on the substrate surface or air trapped in micropores, which expands under heat and breaks through the coating film. Elevator components are mostly made of carbon steel. If they are not thoroughly dried after pretreatment, the risk of pinholes increases significantly.
Solutions: Strictly control the film thickness to no more than 100 μm. Ensure sufficient levels of degassing agents such as benzoin in the formulation. For porous or thick-wall workpieces, consider preheating before spraying so that gases can be released before the coating melts.
- Poor Adhesion and Coating Delamination
Problem: The coating peels away from the substrate or primer, especially at workpiece edges, bends, or after a period of storage.
Possible Causes: Adhesion problems with elevator powder coatings often result from insufficient curing. The curing temperature for epoxy-polyester systems is 180°C/15 min, but the oven display temperature does not represent the actual temperature of the workpiece. This is particularly important when fixtures are heavy or workpieces have thick walls, as areas close to the fixtures may fail to reach the required curing temperature. In addition, residual contaminants caused by inadequate rinsing during pretreatment can also create adhesion problems.
Solutions: Use a temperature profiling instrument to measure the actual surface temperature of the workpiece rather than relying on the oven instrument. Appropriately increase the oven temperature setting to compensate for heat absorption by the workpiece. Strengthen pretreatment cleaning and pre-spraying inspection to ensure that there are no residual contaminants on the workpiece surface.
If you need powder coating for elevator applications or encounter any problems in the powder coating field, please feel free to contact us at any time for professional technical support. We can discuss solutions together and promote the development of the powder coating industry.
We hope this article can provide you with a professional and reliable reference for the powder coating industry. We sincerely welcome your inquiries regarding powder coating product performance, industry standards, application methods, precautions, or any other related questions. Please feel free to leave a message or contact us directly so that we can provide you with more detailed product information, demonstration videos, or customized solutions to help you fully understand the product’s functions and advantages.
