RULES OF THUMB FOR SIZING A HEAT EXCHANGER
The cooler mounts behind an existing TEFC motor, using the electric-motor fan airflow. Cooling flow is obtained from the case drain of the hydraulic machine and is then guided to the integrated electrical machine. Pressure losses in the electrical machine can be seen as negligible. The outgoing flow moves by gravity as long as the outlet and inlet ports are of adequate dimensions. To select the best air oil cooler, provide as much information about the application as possible, including oil heat load in Btu/h or hp, oil flow rate in gpm, maximum inlet oil, and maximum ambient air temperatures during operation. If the required heat dissipation is unknown, it can be estimated that 20% to 30% of the installed horsepower will be converted into heat load. Heat exchangers can be used to remove the excess heat in a hydraulic system. The implementation of a heat exchanger has many variables that need to be taken into account. The heat exchanger and reservoir should be sized when a system is initially designed to remove the generated heat. The reservoir allows some of the heat to dissipate through the walls to the atmosphere. The heat exchangers should be sized to remove the balance of the heat. The heat exchanger needs to be maintained to ensure excess heat is removed. If an air-type heat exchanger is used, the cooler fins should be cleaned regularly. A degreaser may be necessary to clean the fins. To ensure profitable and efficient success in a manufacturing operation, maintaining a proper oil temperature in all hydraulic systems is essential. High hydraulic-fluid temperatures can damage system components and significantly alter the way a hydraulic system performs, resulting in costly repairs and downtime.
• SIMPLE CIRCUIT WITH FLUID MOTORS: 31% • HYDROSTATIC TRANSMISSIONS: 35%-40% • SIMPLE CIRCUIT WITH MINIMAL VALVES: 25% • SERVO-BASED SYSTEMS: 60%-75% • SIMPLE CIRCUIT WITH CYLINDERS: 28%
TYPICAL CASE-DRAIN APPLICATIONS • GEAR BOXES • HYDRAULIC PRESSES • HYDRAULIC TOOLS • HYDRAULIC POWER UNITS • INDUSTRIAL COMPACTORS • ASSEMBLY CONVEYORS
AKG Case-Drain Series
CD SERIES FEATURES: • tube and fin aluminum design, • coolers mount onto the rear of TEFC frame motors, • competitive pricing and assembles from stock, • premium-quality lightweight construction.
Heat Rejection, (hp) 50 Deg ETD
The AKG Thermal Systems CD Series is designed to fit in tight spaces and conveniently mounts onto a power unit with limited envelope space. The narrow profile conditions and cools for a wide array of applications. The AKG tube fin design offers more significant cooling and does not require a protective guard. This cooling setup is compact, low cost, and low flow with minimal heat removal.
CD SERIES
Oil Flow (gpm) Performance for AKG CD Series oil coolers. Listed performance curves are based on ISO VG 32 oil @ 50F ETD.
For more information, visit www.akgts.com.
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