Round Pin Heatsink with Push Pins
Cold-forged round pin heatsinks are the best solution for systems with low to medium airflow rates. Spring-loaded push pins provide a secure mechanism to mount the heatsink.
- Round pin heatsinks are omni-directional – they allow air to come from any direction.
- Round pin heatsinks offer very low thermal resistance at low airflow rates, or when fans are mounted on top of them (fansinks or CPU coolers).
- Our pin fin heatsinks are cold-forged from pure aluminum 1070, which has much higher thermal conductivity than aluminum alloys like 6063 and 6061.
- Both conductive and nonconductive push pins are available (conductive pins can help reduce EMI; nonconductive pins isolate heatsink from PCB).
Please click the part number to view the details of the heat sink, or click “Quote” or “Sample” to request a quote or a sample.
Please note all thermal resistance data are for reference only. They may vary from application to application. Please contact us if you would like us to perform thermal analysis, or determine the actual thermal resistance in your system.
The S802 series are optimized for low to medium airflow rates. For high airflow or impingement cooling (fansink) applications, please contact us for a different design.
The S802 series are designed to work with push pins. Please also visit our S801 and S805 series for non-push-pin series using thermal grease and adhesive tapes.
Other benefits of cold forged round pin heatsinks
Round pin heatsinks also offer low pressure drop, due to its smooth pin shape. Low pressure drop improves heat transfer in the entire system, especially the region behind the heat sink.
In cold forging, the pins are an integral part of the heat sink base – they are simply squeezed out of the base by high pressure. Unlike bonded fin heatsinks, there is no thermal resistance between the pins and the base in cold-forged heatsinks.
In addition to aluminum heat sinks, we also offer round pin heatsinks made of pure copper (C11000). Copper heatsinks typically improve thermal performance by 10-20%. They are recommended for critical applications where a few degrees of temperature reduction can make a big difference.
How to choose the right push pins
Spring loaded push pins are an easy-to-use and highly effective method to secure heat sinks to heat-generating components and PCBs. They provide precise and uniform pressure between the heat sinks and components, and optimize the performance of thermal interface materials. Push pins can be made of nylon, brass or steels.
Nylon push pins are cost effective and perform well when the ambient temperature is relatively low. But the glass transition temperature (Tg) of nylon 6/6 (PA66), the most popular material used in making push pins, is only 45-50°C. Above its Tg, the material will change from its glassy state to rubbery state, and become soft and flexible. For this reason, we recommend nylon push pins for low temperature and cost-sensitive applications, or when electrical insulation is required.
Brass push pins, on the other hand, can withstand high temperatures. They are also electronically conductive and can help reducing EMI by grounding the heat sinks to the PCB. Brass is often preferred over other metals because of their machinability and cost effectiveness. But brass is prone to work hardening and cannot be heat treated (it becomes soft when heat is applied). Without proper release of the work-hardening stress, the reliability and reusability will reduce.
Steel push pins are similar to brass push pins. They can withstand high temperatures and are electronically conductive. Unlike brass, steels have high yield strength and their work-hardening stress can be easily removed through heat treatment. As a result, the push pins can be repeatedly inserted and extracted from PCB holes for more than a hundred times without apparent degradation. They are also more secure than brass push pins when the system experiences strong vibration or shock. We recommend steel push pins for high-temperature and harsh-environment systems, or when electrical conduction is required.
At MyHeatSinks, we offer both steel and nylon push pins in various sizes. They are developed to fit 3.0, 2.5 and 1.5 mm diameter holes. Please visit our heatsink attachment page to find the right push pins that best fit your design.