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Our Mission is to support manufacturers in USA through our expertise in China.
We deliver value-added services that enable companies to manage, improve, and grow their businesses.
Sheet metal work

We offer the complete sheetmetal manufacturing solution, from single part or sub-assembly to turnkey solutions for mechanical and electrical assemblies. With years of manufacturing experience, we have developed an expertise that deliver the finest quality and service.
Aluminium diecasting

P&A offer a range of aluminium die casting services to suit clients needs predominately working with high quality aluminum enclosures and components. The fact that we are China based company enables us to deliver aluminum parts and components at most competitive pricing.

We designed and manufacture a wide variety of thermal solutions for various applications. Our products include U-type heat sinks, extruded heat sinks, cold forged heat sinks, stacked and folded fin heat sinks, heat pipes and heat pipe integrated solutions, TEC's, conduction cooling solutions and more.



Below is a summary of useful documents, images and links. Those been accumulated over the time and are result of the research in corresponding fields by P&A.


P&A International ResourcesQuarter Wave Tube - a resonator used most commonly on air intake systems to reduce resonance. Works over a narrow frequency range, i.e. used to attenuate a specific frequency. The quarter wave tube is open at the end that connects with the air inlet pipe and closed at the other end. The frequency at which the quarter wave tube attenuates is controlled by the length of the quarter wave tube. The maximum attenuation is achieved when the cross-section of the quarter wave tube matches that of the main duct. The quarter wave tube, as per the title, a quarter of a wavelength long. The total distance that the acoustic wave travels is half a wavelength. Therefore, in the time taken for the acoustic wave to travel down the quarter wave tube and back to the main duct the acoustic wave in the main duct has moved along half a wavelength. The following link shows diagram and the operation of the quarter wave tube. Periodic Table of Elements Sorted by Thermal Conductivity Link below is for Calculators and Simulation Tools offered by University of Waterloo.

Calculator and a source


Thermal Fluid Properties Calculator

Section Properties Selected Shapes

Machining Feeds and Speeds Calculator

Periodic Table of Elements Sorted by Thermal Conductivity

P&A Electronic Components Range

P&A Membrane Switch Document

Titanium Products Range

Heat Sink Performance Simulation software

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