AFT Blog

 Unnecessary Background Codes and standards are not sexy topics, nor are they liked by the rebellious at heart. Whether you love or hate them they are a part of the world and aim to make it a safer place. One of the largest organizations to compose standards is the American Society of Mechanical Engineers (ASME). They have been around sin...

The pistons, or diaphragm of a reciprocating (positive displacement) pump causes a cyclical variation, typically in some sinusoidal form, of both flow in pressure in a piping system. The magnitude varies, depending on the type and design of the pump. What is acceleration head? Acceleration head is the energy required to change the velocity of the liquid in the system from an at rest, or zero condition, to some non-zero value. To help us understand acceleration head a little more clearly, you could compare it to a race car. In a drag race, the race car will accelerate to some maximum velocity,...

Summary Engineers are often responsible to design systems to comply with codes and standards. In recent years codes that apply to waterhammer and surge pressures have become more prominent. Increasingly AFT Impulse is being used to help engineers comply with such codes. Once AFT Impulse has calculated the maximum pressure due to a transient event, what shall the designer do with this value? The answer to this question depends on the code that is being used as the piping design basis. In this article, we’ll be discussing how two important piping design codes - B31.4 and B31.3 - deal with surge...