Service

Moisture and Dust Protection: Potting can block the entry of air, moisture and dust, avoiding the circuit board from moisture, pollution and corrosion.

Mechanical protection: Gluing can increase the mechanical strength of the circuit board, reduce vibration and shock damage to the circuit board, improve the shock resistance and reliability of the circuit board.

Insulation Protection: Gluing provides an electrically insulating layer to prevent short circuits and leakage between circuit boards, and improves the circuit board‘s voltage resistance.

Thermal management: Gluing materials can have good thermal conductivity, help the circuit board heat dissipation, to maintain the operating temperature of the circuit board in the appropriate range, to improve the performance and reliability of the circuit board.

Anti-corrosion: Potting can prevent corrosion of the metal components on the board, extending the life of the board.

Confidentiality Requirements: By potting circuit boards, unauthorised personnel can be prevented from accessing the design and layout information on the boards, thereby protecting intellectual property and trade secrets. Potting increases the board‘s tamper resistance and reduces the risk of information leakage.

Potting (potting) is the polyurethane potting adhesive, silicone potting adhesive, epoxy resin potting adhesive with equipment or by hand into the device equipped with electronic components, circuits, curing at room temperature or under the condition of heating to become a thermosetting polymer insulation with excellent performance, so as to achieve bonding, sealing, insulation material, so as to achieve bonding, sealing, and so on.

Material, so as to achieve the purpose of bonding, sealing, potting and coating protection.

Potting adhesive English name: Potting of smidahk; used for electronic components bonding, sealing, potting and coating protection. Potting compound is liquid before curing, with fluidity, viscosity of the glue according to the material of the product, performance, production process and different. Potting compound completely cured to achieve its use value, after curing can play a waterproof moisture, dust, insulation, thermal conductivity, confidentiality, anti-corrosion, temperature resistance, shockproof role.

Electronic potting compound type is very much, from the type of material to points, the current use of the most common most of the three main types, namely, epoxy resin potting compound, silicone resin potting compound, polyurethane potting compound, and these three materials can be subdivided into several hundred different types of potting compound.

Introduction: Epoxy resin potting adhesive is mostly hard, after curing and stone almost hard, it is difficult to remove, with good confidentiality, but there are a small number of soft. Ordinary temperature resistance of about 100 ℃, heating curing temperature resistance of about 150 ℃, there are also temperature resistance of more than 300 ℃. There are fixed, insulating, waterproof, oil, dust, anti-theft, corrosion resistance, aging resistance, resistance to hot and cold shock and other characteristics. Common epoxy potting adhesive: flame retardant, thermal conductivity, low viscosity type, high temperature type.

Advantages: good adhesion to hard materials, excellent high temperature resistance and electrical insulation, easy to operate, very stable before and after curing, excellent adhesion to a variety of metal substrates and porous substrates.

Disadvantages: weak resistance to hot and cold changes, easy to produce cracks after being subjected to hot and cold shocks, resulting in water vapour seeping into the electronic components from the cracks, poor moisture resistance. Moreover, the hardness of the cured colloid is high and brittle, which is easy to strain the electronic components, and it can‘t be opened after potting, so the reparability is not good.

Scope of application: epoxy resin potting compound is easy to penetrate into the product gap, suitable for potting small and medium-sized electronic components at room temperature and no special requirements for the mechanical properties of the environment, such as automotive, motorbike ignition, LED drive power supply, sensors, toroidal transformers, capacitors, triggers, LED waterproof lamps, circuit boards, confidentiality, insulation, moisture-proof (water) potting.

Introduction: Silicone electronic potting adhesive cured more soft, flexible can be repaired, referred to as soft glue, poor adhesion. Its colour can generally be adjusted according to need, or transparent or non-transparent or colour. Two-component silicone potting adhesive is the most common, this type of adhesive including condensation type and additive agent of the two categories. General shrinkage type of components and potting cavity adhesion is poor, the curing process will produce volatile low molecular substances, after curing there is a more pronounced shrinkage; add the moulding (also known as silicone gel) shrinkage is very small, the curing process will not produce volatile low molecular substances, can be heated to fast curing.

Advantages: strong aging resistance, good weather resistance, excellent impact resistance; excellent resistance to hot and cold changes and thermal conductivity, can be used in a wide range of operating temperatures, can be used in -60 ℃ ~ 200 ℃ temperature range to maintain the elasticity of non-cracking, can be used for a long period of time in the 250 ℃, heating curing type of resistance to higher temperatures, with excellent electrical properties and insulation ability, insulation performance is better than the epoxy resin, can be Withstand voltage more than 10000V. After potting, it can effectively improve the insulation between internal components and lines, and improve the stability of electronic components; it has no corrosion on electronic components and does not produce any by-products in the curing reaction; it has excellent repair ability, and can be quickly and conveniently taken out of the components after sealing to repair and replace them; it has excellent thermal conductivity and flame-retardant ability, and can effectively improve the heat dissipation ability and safety coefficient of electronic components; Low viscosity, good fluidity, able to penetrate into the small gaps and components below; room temperature curing can also be cured at high temperature, good self-bubbling, more convenient to use; curing shrinkage is small, with excellent waterproof performance and seismic capacity.

Disadvantages: high price, poor adhesion.

Scope of application: suitable for potting all kinds of electronic components working in harsh environments.

Introduction: polyurethane potting adhesive, also known as PU potting adhesive, cured more soft, flexible can be repaired, referred to as soft glue, adhesion between epoxy and silicone, temperature resistance is general, generally not more than 100 ℃, after potting more bubbles, potting conditions must be in a vacuum, adhesion between epoxy and silicone.

Advantages: good low temperature resistance, anti-vibration performance is the best of the three. Low hardness, moderate strength, good elasticity, water resistance, anti-mould, shockproof and transparent properties, excellent electrical insulation and flame retardant, no corrosion of electrical components, steel, aluminium, copper, tin and other metals, as well as rubber, plastics, wood and other materials have good adhesion.

Disadvantages: poor resistance to high temperature, the surface of the cured gel is not smooth and poor toughness, aging resistance and UV resistance are weak, the gel is easy to discolour.

Scope of application: suitable for potting indoor electrical components with low heat generation, which can make the installed and debugged electronic components and circuits free from vibration, corrosion, humidity and dust, etc. It is the ideal potting material for the moisture-proof and corrosion-proof treatment of electronic and electrical parts.

In addition to the above three common sealants, there are two other relatively common:

Polyacrylate potting compounds are suitable for the protection of sensors and connection points that require high oil resistance and are often used in the automotive industry. Thanks to their excellent protection and fixation features, especially with the development of electric vehicles and ADAS systems, this formulation is highly sought after in the market.

Electronic Potting Gel offers an innovative formulation for applications where traditional potting gels are not suitable. This new technology transparently pots components and assemblies with a soft, flexible cured surface and excellent dimensional stability.

   (1) Requirements for performance after potting: use temperature, hot and cold alternating conditions, components to withstand internal stress, outdoor use or indoor use, stress conditions, whether the requirements of flame retardant and thermal conductivity, colour requirements and so on;

   (2) potting process: manual or automatic, room temperature or heating, complete curing time, the solidification time of the glue after mixing;

   3) Cost: the specific gravity of the potting material varies greatly, we must look at the actual cost after potting, rather than simply look at the selling price of the material.

Adhesives used for potting, according to the functional classification of thermal conductivity potting adhesive, adhesive potting adhesive, waterproof potting adhesive; according to the material classification of polyurethane potting adhesive, silicone potting adhesive and epoxy resin potting adhesive, for the choice of soft or hard glue, when both can be potting, waterproof insulation, if the requirements of the high-temperature thermal conductivity, then it is recommended that the use of organosilicone soft adhesive; if the requirements of low-temperature resistance, it is recommended that the use of soft polyurethane adhesive; If there is no special requirements, it is recommended to use polyurethane adhesive If there is no special requirements, it is recommended to use epoxy hard glue, because epoxy hard glue is faster than silicone curing time.

Epoxy resin potting adhesive has a wide range of applications, technical requirements are very different, there are many varieties. From the curing conditions on the points of room temperature curing and heating curing two categories; and from the agent type on the points of two-component and one-component two categories, there is room temperature curing epoxy potting adhesive is generally two-component, its advantage lies in the potting does not need to be heated to curing, on the equipment requirements are not high, easy to use, there are defects is the glue mixture operation viscosity, poor immersion, short application period, and the cured material of the thermal and electrical properties are not very high, generally used for low-voltage electronic products. High, generally used for low-pressure electronic device potting or should not be heated curing occasions.

Electronic Potting: Potting blocks protect sensitive electrical and electronic components from a wide range of operating conditions such as temperature fluctuations, moisture, vibration etc.

Plug and cable potting: Potting compounds fill extremely small gaps in plug housings, connectors and power supply units. Potting materials for plugs and cables are elastic, highly waterproof, mechanically stable and tear-resistant.

Optoelectronic potting: Optoelectronic potting brings a high degree of weather resistance to equipment, protects electronic devices from environmental influences and protects against moisture and humidity.

LED Potting: Transparent or opaque potting systems protect LEDs from water, dust and other atmospheric influences for effective encapsulation and optimal illumination of spotlights.

Filter potting: Used to attach end caps to various filters, as well as bonding filters to the filter frame and ensuring a tight seal for a seamless seal and cleaner filtered air. Foamed potting material bonds the filter media into the filter frame, enabling cost and weight savings while still meeting high quality requirements. The amount of adhesive used per filter can be reduced by up to 50 per cent due to the foam structure. The lower density reduces weight and facilitates the handling of parts.

The quality of potting products is mainly closely related to product design, component selection, assembly and potting materials used, and the potting process is also a factor that should not be ignored. Epoxy potting has two kinds of potting process: normal and vacuum.

Epoxy resin. Amine room temperature curing potting material, generally used for low-voltage electrical appliances, mostly using normal potting.

Epoxy resin. Anhydride heating curing potting material, generally used for high-voltage electronic devices potting, mostly using vacuum potting process.

At present, there are common manual vacuum potting and mechanical vacuum potting two ways, and mechanical vacuum potting can be divided into A, B components first mixed defoaming after potting and first separate defoaming after mixed potting two cases. There are three operation methods:

The first: single-component electronic potting adhesive, direct use, can be used to snatch the fight can also be directly infused;

The second type: two-component shrinkage type electronic potting adhesive, curing agent 2% -3% or other proportion, mixing - vacuum defoaming - potting;

The third type: additive moulding electronic potting adhesive, curing agent 1:1, 10:1;

The process flow is as follows:

(1) Manual vacuum potting process

(2) Mechanical vacuum potting process

(1) Measurement: accurately weigh the A component and B component (curing agent).

(2) Mixing: mix the components;

(3）Defoaming: natural defoaming and vacuum defoaming;

(4) Filling: the adhesive should be filled within the operating time otherwise it will affect the levelling;

(5) curing: heating or room temperature curing, potting products at room temperature curing, after the initial solid can enter the next process, the full curing takes 8 to 24 hours. Summer temperature is high, the curing will be faster; winter temperature is low, the curing will be slower.

(3) Precautions:

a, the surface of the product must be cleaned before sealing!

b, Note that before weighing, mix the A and B components well respectively, so that the pigment (or filler) which sinks to the bottom can be dispersed into the glue.

c, the primer must not be mixed directly with the adhesive, the primer should be used first, after the primer is dry, then the adhesive should be potted with this adhesive.

d, the curing speed of the adhesive has a certain relationship with the temperature, low temperature curing will be slower.

In contrast, mechanical vacuum potting, equipment investment, maintenance costs are high, but the consistency and reliability of the product is significantly better than the manual vacuum potting process. No matter what kind of potting method, should strictly comply with the set process conditions, otherwise it is difficult to get satisfactory products.

(1) How to solve the poisoning of electronic potting compound without curing? Silicone poisoning generally occurs in the additive electronic potting gel, poisoning silicone will appear after the phenomenon of non-curing, so the use of additive sealant should be avoided with phosphorus, sulfur, nitrogen-containing organic compounds in contact, or with the additive silicone at the same time the use of polyurethane, epoxy resins, unsaturated polyester, condensed room temperature vulcanisation of silicone rubber and other products, to prevent the occurrence of poisoning does not cure the phenomenon.

(2) What can I use to clean the electronic potting gel that I accidentally stuck to?

Commonly used silicone cleaning agents are mainly alcohol, acetone, white spirit, etc., remember to dilute coated when used.

(3) winter electronic potting compound can not dry how to do?

Due to the winter temperature is very low, resulting in electronic potting adhesive in the mixing curing is very slow or even a long time does not cure, so we can improve the curing temperature, you can put the good glue products in the oven at 25 ℃ curing.

Semi-automatic gluing machine: When gluing the product, put it next to the assembly line, put the product under the gluing head manually, press the start switch, the machine will be automatically gluing, and the gluing will be stopped automatically. Then the operator will put the glued products on the assembly line, semi-automatic gluing machine is suitable for all kinds of PCBA products, regardless of size.

Automatic gluing machine: If the majority of small products, gluing is also very simple, put the product into a fixture, and then put the fixture to the gluing machine table, press start, the machine will start to fill the glue, and so on all the filling is completed, automatic stop, and then the operator will be the fixture from the table, and then put another loaded with the product of the fixture, press start, and so on. The operator has to do is to put the fixture and press the start button.

Full-automatic gluing line: put the fixtures with products on the transfer line, the machine will automatically fill the glue, and automatically feed the materials to the oven, saving labour and running efficiently.

The above is the 3 methods of automatic glue filling, the use of automatic glue filling equipment can better save labour and improve production efficiency.

Aldeno Technology Limited can provide you with high quality electronic glue filling service to ensure that your circuit boards have excellent waterproof, dustproof and shockproof performance. Using state-of-the-art glue filling machines and their highly reliable processes, we provide you with customised solutions to ensure that every project receives the best quality and efficiency. Our dedicated team will ensure that tasks are completed within tight schedules and provide full after-sales support to ensure that our customers are satisfied with our services. When you work with Aldenor, Aldenor will wholeheartedly serve you and do our best to meet your needs, we look forward to working with you, thank you!