Pumps & Piping Systems Flashcards
(38 cards)
A(n) ____________ is an assembly which is used to house a gland seal. It is used to prevent leakage of fluid, such as water or steam, between sliding or turning parts of machine elements.
stuffing box
___________ is a spontaneous vaporization of the fluid inside a pump, resulting in a degradation of pump performance, as well as noise, vibration, impeller pitting, and structural damage to the pump casing.
Cavitation
Why is this concentric reducer arrangement to be avoided?
There is a risk of large air bubbles growing in the high point and eventually being swept into the pump impeller.
About what thickness of grout would be typical under a pump skid?
1-1/2”
A(n) _______________________ for a pump and piping system refers to the study of how the system behaves when there are sudden changes in flow, pressure, or operating conditions. These changes can result from events such as starting or stopping pumps, valve closures or openings, changes in load, or other time-varying disturbances that affect the system. The goal is to understand the dynamic response of the system, including pressure surges, flow variations, and the potential for damage or inefficiencies caused by these transients.
transient analysis
Name four (4) scenarios where a VFD for a new pump would be a good idea.
- Variable flow requirements: When the system needs different flow rates depending on the situation, like in a building with varying water usage throughout the day.
- Maintaining constant pressure: If a constant pressure needs to be maintained even when the flow rate changes, a VFD can adjust the pump speed to compensate.
- Energy efficiency: By allowing the pump to operate at a slower speed during low demand periods, a VFD can significantly reduce energy consumption.
- Pump protection: VFDs can help protect pumps from damage by preventing sudden starts and stops, and by allowing for soft starts and smooth acceleration.
One of the most common transient phenomena in pump and piping systems is ______________. It occurs when a sudden change in flow velocity (such as closing a valve quickly or turning off a pump) causes a pressure wave to travel through the system. This pressure wave can lead to dangerous pressure spikes, vibration, and even rupture of pipes if not properly controlled.
Water hammer
What type of pump are these?
Vertical multi-stage pumps
What type of pump are these?
Vertical single-stage centrifugal pumps
Name some advantages of a vertical centrifugal pump over a horizontal centrifugal pump.
- Better suitability for high suction lift applications.
- Flexibility in installation in deep wells or sumps.
- Reduced vibration and noise.
- Ability to handle high flow rates with a smaller footprint, especially in multi-stage designs.
Name some advantages of a horizontal centrifugal pump over a vertical centrifugal pump.
- Simpler design and maintenance, which makes them easier to operate and repair.
- Lower initial cost and better cost-effectiveness for many standard industrial applications.
- Higher efficiency in typical low-to-moderate pressure and flow applications.
- Versatility, with a wide range of applications in industries such as water treatment, chemical processing, and cooling systems.
What is represented by this line in this flow diagram?
Minimum continuous stable flow
Name at least one software application that can perform a transient analysis?
AFT Impulse, Synergi Pipeline Simulator, WinTran, KYPipe Surge, and PIPENET Transient Module. All of these are designed to simulate pressure surges and water hammer events within piping networks by analyzing rapid changes in flow conditions over time.
What is the wall-mounted device in this picture?
VFD (Variable Frequency Drive)
A(n) _______________ is an electrical device that controls the speed of an electric motor by varying its input voltage. They are used to control pumps, fans, conveyor belts and other types of machinery in industrial plants.
VFD (Variable Frequency Drive)
A(n) __________________ is simply a method of containing fluid within a vessel (typically pumps, mixers, etc.) where a rotating shaft passes through a stationary housing or occasionally, where the housing rotates around the shaft. This does not include packing.
mechanical seal
What is the alternative to a mechanical seal, if a mechanical seal is not used?
Mechanical packing, also known as packing or gland packing
What is this piece of equipment called?
Hydropneumatic tank (aka pressure tank)
If a pump has a stuffing box, can it also have a mechanical seal?
Yes, a pump with a stuffing box can also have a mechanical seal; in fact, a mechanical seal is often installed within the stuffing box of a pump, effectively replacing the traditional packing material that would otherwise be used in the stuffing box to create a seal around the rotating shaft.
What is a stuffing box for a pump?
A stuffing box is a chamber around the pump shaft where sealing material (like packing) is placed to prevent fluid leakage. Alternatively, a mechanical seal may be installed within the stuffing, effectively replacing the traditional packing material.
What is attached to the pipe in this picture?
Tracer wire
What is the purpose of tracer wire?
Tracer wire is used to locate buried utilities, such as pipes, cables, and irrigation systems. It’s buried alongside the utility during installation and helps workers find it later.
To find the utility, a technician uses a transmitter to send a signal through the tracer wire. A receiver then pinpoints the location of the wire, which indicates the location of the utility.
Green tracer wire typically indicates what kind of utility?
Sanitary sewer systems
Red tracer wire typically indicates what kind of utility?
Electrical power
