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What does Delta-P mean?

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Delta P (ΔP), is differential pressure in a piping system, where a liquid is passing through piping, valves and couplings. 
Delta or Δ is a mathematical symbol, which represents the difference between two values.  P stands for pressure. 

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ΔP stands for the difference between two measured pressure values. Measurement at different positions in a system.  You compare the pressure at the input with the pressure at the output of a hydraulic system  And get the pressure drop - Delta P.

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To determine Delta P across a coupling, simply subtract the outlet pressure (P2) from the inlet pressure (P1).  The equation is (P1) –(P2)= ΔP

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Why does pressure drop matter?

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Pressure drop is a critical element in coupling or ball valve sizing and valve application. Pressure drop must be known by the engineer designing the system to ensure proper valve selection.

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What does MWP mean?

 

MWP stands for Maximum Working Pressure

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What is ISO 16028 and ISO 7241?

 

ISO stands for International Organization for Standardization.  Manufactures follow the standard that governs the specifications for a particular type of coupling.  For example, standard Flat Face couplings are manufactured to the ISO 16028 Standard.  Therefore, different manufactures couplings will connect with each other.

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What does DN mean?

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DN = Diametre Nominal. The nominal diameter is specified according to EN ISO 6708 using the abbreviation DN (Diameter Nominal) followed by a dimensionless number corresponding to the approximate internal diameter in millimetres.

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Why will my couplings not connect?

 

It is likely that there is pressure in the line.  Release the pressure from the circuit and then try to connect the couplings again.

 

Why will my coupling not disconnect?

 

The same reason as they will not connect, it’s down to pressure being in the circuit.  Release the pressure and the couplings will be able to disconnect.

 

Should I tap the couplings with a hammer to release trapped pressure?

 

No, this should never be done.  It is very likely that the coupling will be damaged if struck with a hammer or similar tool.  Once damaged, the coupling will need replacing.

 

How long will a coupling last?

 

The average life of hydraulic coupling are dependant on the application and usage.  It is estimated an average of 5 years for agricultural applications and 2 years for construction applications

A pneumatic coupling can last up to 10 years or more if maintained correctly.