Air Cooled

Uses a fan to discharge heat from the finned coil to the outdoors.

Ambient Temperature

The temperature, usually of the air, that surrounds operating equipment.

Batch Furnace

A heat treating furnace where the load enters the quench tank at predetermined times, all at once.  For example, a Surface Combustion Allcase batch furnace may have a 2500-pound load entering the quench tank once every two hours.  The SBS cooler will then have two hours to cool the quench tank down before the next cycle.  A pusher furnace, like an AFC-Holcroft pusher, is considered a batch furnace even though the cycles may be as low as every six minutes.

BTU (British Thermal Unit)

The standard of measurement used for measuring the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.


A condition affecting an operating pump whereby the pump suction is not fully flooded with fluid being pumped. Pump cavitation may result from inadequate or restricted supply or from the introduction of air or gas into the fluid stream.  It is an undesirable condition that causes a reduction in pump efficiency and excessive wear or damage to pump components.  A user will hear the sound of gravel being pumped if the pump is experiencing cavitation..


The pump that moves the refrigerant from the indoor evaporator to the outdoor condenser and back to the evaporator again.  The compressor is often called “the heart of the system” because it circulates the refrigerant through the loop.


A device that transfers unwanted heat out of a refrigeration system to a medium (either air, water, or a combination of air and water) that absorbs the heat and transfers it to a disposal point.  There are three types of condensers: air-cooled condensers, water-cooled condensers, and evaporative condensers.  The evaporative condenser uses a combination of air and water as its condensing medium.  Most residential systems have an air-cooled condenser.

Condenser Coil

A series or network of tubes filled with refrigerant, normally located outside the home, which removes heat from the hot, gaseous refrigerant so that the refrigerant becomes liquid again.

Continuous Furnace

A heat treating furnace where the load enters the quench tank at a constant rate, not varying.  For example, a Can-Eng mesh belt furnace may have a 4,000-pound-per-hour load entering the quench tank constantly, like in the heat treating of fasteners.  The parts trickle into the quench tank at a constant rate.  The SBS cooler will have to keep the quench tank at the desired temperature all the time, with no temperature spiking.


An enamel coating over aluminum finning for corrosion protection.  Popular in applications for protecting a Quench Air’s aluminum fins from sea water corrosion.  Copon finning appears deep blue in color.

Dry Bulb Temperature

The temperature of air measured by a thermometer shielded from radiation and moisture.  SBS air-cooled heat exchangers are very concerned with the dry bulb temperature.  The dry bulb temperature is what the weatherman would use to describe the temperature outside.  In evaporative heat exchanger (i.e. cooling towers) you will hear the opposing term, found below, wet bulb temperature.


A special nozzle utilizing a unique “venturi” design which enables a small flow to agitate a tank like a large flow.  The eductor can circulate four to five gallons of fluid for each gallon pumped.  Useful to sweep debris off a tank’s floor into a pump’s suction.


A general term in the heat exchanger industry to denote an air-cooled heat exchanger similar to SBS’ Quench Air.

Heat Load

Weight of Steel (lbs.) x Temperature Differential x Specific Heat-Steel


Stands for Net Positive Suction Head.  This measures the difference between the liquid pressure and the liquid vapor pressure in a pumping circuit.  NPSH is an important parameter because if the NPSH required is less than the NPSH available, liquid boiling occurs which leads to cavitation which leads to ruined impellers and pumps.  In oil pumping, it’s less critical than in water pumping.  Hot water pumping is where NPSH absolutely needs to be considered.

Pipe Size

Absolutely the most common installation mistake that we see is undersized piping.  The most common excuse that we hear for this very expensive mistake is, “I just matched the pipe to the size of the inlet and outlets on the pump.”  Proper pipe size has nothing to do with the inlets and outlets on the pump you are installing.  Let me explain.  Nearly all pumps were designed back in the 1940s, 50s, and 60s.  Back then, primarily because of bearing quality, all pumps ran at much slower speeds (in most cases either 1200 or 1800 RPM).  Today’s evolved motors are now able to power pumps at 3600 RPM for years of trouble-free operation.  Doubling the speed of a pump (from 1800 RPM to 3600 RPM) results in 2X the flow, 4X the pressure and 8X the horsepower used — all from a pump that was originally designed to deliver much less flow and pressure.  Always consult the Pump Selector when designing a piping system.  Don’t pay any attention to the inlets and outlets on your pump!  Also see — Total Dynamic Head

Relative Humidity

Is the ratio of the amount of water vapor in air to the maximum amount of water vapor that could be in the air if the vapor were at its saturation conditions.

Temperature Rise of Batch Load

(Heat Load) / (Pounds of Oil x Specific Heat of Oil)

Total Acid Number

(Abbreviated TAN) is the number expressed in milligrams (mg) of potassium hydroxide needed to neutralize the acid in one gram of oil.  The test is used to indicate the amount of oxidation that the fluid has undergone.  The TAN increases as the fluid undergoes increased amounts of oxidation.

Total Dynamic Head

A term to reflect pump pressure is the total head (another word for pressure) that the pumping system is working against.  It is the total head that the pump must overcome to move the fluid.  In reality this includes friction losses through the pump intake, in the pump column, and through the pump head.  Pumps aren’t rated in PSI (pounds per square inch) as the PSI reading is dependent on the fluid’s density, i.e. water and quench oil will give different PSI readings under the same pumping conditions (because quench oil is 15% lighter than water and is pushing down with 15% less gravity).

Volumetric Expansion

A basic law of physics states that if a vessel is filled with liquid so that no space remains for volumetric expansion, any rise in temperature of the liquid will cause an increase in internal pressure.  This is due to the tendency of liquids to change in volume.  As liquids are relatively incompressible, the pressure builds up rapidly with only a slight temperature rise.

Wet Bulb Temperature

Is a temperature that takes into account the relative humidity and the dry bulb temperature (defined above).  At any given ambient temperature, less relative humidity results in a greater difference between the dry-bulb and wet-bulb temperatures.  Houston, TX, with its high dry bulb temperature and high relative humidity will have a higher wet bulb temperature than Phoenix, AZ, with its high dry bulb temperature but low relative humidity.