📘 Case background
In today’s rapidly developing era of intelligent manufacturing and industrial automation, electrical control boxes, as key electronic integration modules, are widely used in various fields such as rail transit, power systems, new energy equipment, industrial robots, etc. The control box integrates a large number of power modules, control chips, sensors, and power devices inside. These components will continue to generate heat during long-term operation, leading to module temperature rise and affecting its stability and service life.
In order to ensure the long-term stable operation of the control box in harsh environments, sealing glue is often used to protect it. It not only plays a role in waterproofing, dust prevention, and shock resistance, but more importantly, it provides thermal management function to timely dissipate the heat generated during device operation, reduce thermal accumulation, and avoid device overheating and failure.
In the client’s project, a control box for an industrial automation equipment needs to undergo thermal conductive sealing treatment. The main requirements of the customer for sealing materials are as follows:
Thermal conductivity: 0.6~0.8 W/m · K, meeting the needs of daily industrial use;
Moderate viscosity: has good fluidity and can fully fill the gaps inside the control box;
Good electrical insulation: Ensure that it does not affect the operation of the circuit after encapsulation;
After curing, it has a certain degree of flexibility: to avoid stress concentration caused by thermal expansion and contraction;
The most important point is to control the cost within 20 yuan/kg and have the conditions for large-scale use.
Control box thermal conductivity sealing
⚠️ Challenges Faced
During the material selection process, customers faced the following challenges:
one ️⃣ It is difficult to balance the thermal conductivity and cost of materials
Traditional high thermal conductivity sealing materials, such as silicone systems or epoxy systems with abundant fillers, although their thermal conductivity can reach or even exceed 1.0 W/m · K, their raw material prices are expensive and the process is complex, with unit costs often ranging from 30 to 50 yuan/kg, far exceeding customer expectations, and their cost-effectiveness is relatively low for medium thermal conductivity needs.
two ️⃣ Poor reliability of mid to low end products on the market
Although some low-priced thermal conductive sealing adhesives are cheap, they have problems such as false thermal conductivity, layered fillers, powdering or cracking after long-term aging. As one of the core components of industrial equipment, the control box operates in complex environments (such as high temperature, high humidity, vibration, etc.), requiring adhesives to have long-term reliability and cannot be “dealt with in the short term”.
three ️⃣ The sealing process requires high efficiency and consistency
The customer’s production line is automated sealing, requiring glue to have a good operating window, including suitable operating time, moderate viscosity and flowability, and requiring stable volume and no bubbles after curing to ensure consistent quality of each batch of control boxes.
✅ Solution: SIPA 8250 Thermal Conductive Sealing Adhesive
Based on customer needs and pain points, we recommend using SIPA 8250 thermal conductive potting material. This is an economical two-component epoxy system potting adhesive developed specifically for thermal management and protection of industrial electronic devices, with the following advantages:
🎯 Performance matching
Thermal conductivity: about 0.7 W/m · K, located at the median value of customer demand, can effectively assist in heat conduction;
High dielectric strength: excellent electrical insulation performance, suitable for electronic circuit packaging;
Moderate viscosity: suitable for automatic dispensing equipment sealing, smooth pouring without dead corners;
Moderate flexibility after curing: no brittle cracking, no shrinkage, able to adapt to thermal expansion and contraction.
💰 Cost controllable
The comprehensive cost of materials is much lower than the cost of imported thermal conductive adhesive, which helps customers significantly reduce their material budget;
No additional primer or special equipment is required during use, simplifying the process flow and further reducing production costs.
🏭 Good process adaptability
The two-component ratio is 1:1, easy to mix, suitable for use in fully automatic sealing lines;
Adequate operation time (>30 minutes) effectively avoids interruptions or hardening issues during the sealing process;
Both room temperature curing and heating curing are available, and customers can flexibly choose the process plan according to the production pace.
🔧 Actual application effect
The customer used SIPA 8250 for overall sealing of the power module area inside the control box during small batch verification, and the actual operating effect is as follows:
Significant improvement in thermal management: After infrared thermal imaging detection, the chip temperature decreased by 8-12 ℃ after encapsulation, and the overall stability of the machine was improved;
Good material compatibility: for metal terminals PCB、 The plastic shell has no corrosion phenomenon and the packaging interface is well bonded;
Excellent environmental adaptability: no cracking or bubble detachment after high and low temperature impact testing (-40 ℃~125 ℃), stable performance;
Customer feedback unanimously praised SIPA 8250: “The performance is just right, the price is also just right, and the cost-effectiveness is very high” has become a high praise from customers for SIPA 8250.
🧪 Summary and Recommendation
The selection of thermal conductive sealing materials should not only focus on the “thermal conductivity” indicator, but also comprehensively consider their electrical performance, reliability, construction convenience, and cost control. SIPA 8250, as a cost-effective thermal conductive sealant, has been widely used in various industrial control, power module, and new energy equipment, especially suitable for the following scenarios:
Control system for moderate heat release;
Projects that are sensitive to the cost of potting adhesive;
Application scenarios that require batch automated encapsulation.
If you are struggling with thermal management sealing for control boxes or other electronic modules, you may want to try SIPA 8250 or contact a professional technical team to customize a customized solution for you.
Tags: Thermal sealing adhesive · Control box thermal sealing · Organic silicon thermal sealing adhesive · Organic silicon sealing adhesive · Sealing adhesive
