The screw compressor is primarily composed of a pair of helical rotors that engage and rotate within the compressor body. Sealed chambers be formed with rotor's consecutive teeth and the surface of the pump body cavity, the volume of this chamber changes as the engagement progresses, facilitating the intake and discharge of fluids through convection. In comparison to traditional reciprocating compressors, screw compressor rotors undergo rotational motion, allowing for higher operating speeds, lower contact stress, smoother operation, and a compact structure. Currently, it finds widespread applications in fields such as compressors, vacuum pumps, refrigeration equipment, and boosting devices.
The screw compressor emerged in the 1930s and gained widespread adoption in the mid-1960s with the use of asymmetric profiles, achieving acceptable efficiency levels. The characteristics of the rotor profile directly determine the efficiency, wear life, noise, and vibration. The construction of the rotor profile is complex, involving high computational difficulty. Additionally, the cost of prototyping is high due to the need for specialized tools. International companies are continuously working on improving the performance of screw compressors, introducing several new profile designs. These profile technologies serve as technological signatures and product highlights for companies, forming industry technological barriers.
The Cotegral® algorithm developed by APT, breaks through the constraints of traditional profile solving, rendering the integration and conjugate solving of complex and segmented curves more convenient and feasible. Tailored to specific design objectives, select specific function curves (conical curves, epitrochoids, involutes, high-order curves, etc.) and combine them based on particular numerical relationships. Subsequently, we obtain primary target profiles through composite integration and inverse enveloping. This process allows for seamless simulation analysis directly within APT's software. The efficient iteration within the software facilitates the rapid attainment of optimal solutions, making the development of new profiles more convenient and feasible.
APT's design software can solve various type of existed profiles in the industry, and has developed series of new profiles based on market requirement and customer feedback. These new profiles achieve larger volume displacement and better sealing effects (longer sealing lines). Based on actual application scenarios and technical requirements, determines the weights of specific target characteristics (displacement, efficiency, NVH). Then chooses the particular profile types, performs preliminary design, and undergoes multi-parameter optimization, achieving customized optimization for part contact characteristics, pump volume efficiency etc.
The images above showcase various rotor profiles of APT's screw compressors, with each profile type maturely applied in multiple fields. APT's technology also allows for the customization of entirely new specialized profiles based on customer-specific or specific technical requirements.