Hydraulic and Pneumatic Accessories:Hydraulic coolers and Heat exchangers

Hydraulic coolers and Heat exchangers

Despite the occasional use of heaters mentioned earlier, the problem with oil temperature is usually keeping it down to the required 50 °C. In small systems, the heat lost through reservoir walls is sufficient to keep the oil cool, but in larger systems additional cooling is needed. Table 6.1 shows typical heat losses

Hydraulic and Pneumatic Accessories-0138

Hydraulic and Pneumatic Accessories-0139

Figure 6.7 shows two types of cooler and their symbols. Water cooling is most common and Figure 6.7a shows the usual form of a shell and tube heat ex- changer which is fitted in the return line to the tank. Note that the cooling water flows in the opposite direction to the oil (giving rise to the term: counter-flow cooler). If the system is open to atmosphere and liable to stand unused in cold weather, protection must be included to prevent frost damage which can result in water-contaminated oil.

Air cooling is also common, shown in Figure 6.7b, with fans blowing air through a radiator matrix similar to those in motor cars (but, obviously, with a far higher pressure rating). Air cooling is noisy and occupies more space than a water cooler, but does not have the danger of contamination from leaks inside a water cooler.

Related posts:

Pumping system hydraulic characteristics:System characteristics
Energy and Efficiency:HEAT RECOVERY
System selection considerations:Power requirements and Influence of conveying distance.
First approximation design methods:Universal conveying characteristics method.
HYDRAULIC FLUIDS:Density and Compressibility
Control components in a hydraulic system:Shock absorbers
Hydraulic cylinders:Construction
Hydraulic circuit design and analysis:Hydraulic circuits
Converters:I-P converters and P-I converters.
Air Compressors, Air Treatment and Pressure Regulation:dynamic compressors
PROPERTIES OF PURE SUBSTANCES:SPECIFIC HEATS
THE SECOND LA W OF THERMODYNAMICS:INTRODUCTION TO THE SECOND LAW
RANKINE CYCLE: THE IDEAL CYCLE FOR VAPOR POWER CYCLES
SUMMARY OF INTRODUCTION TO FLUID MECHANICS
HEAT EXCHANGERS:THE EFFECTIVENESS–NTU METHOD

Leave a comment

Your email address will not be published. Required fields are marked *