Gaskets and Piping Flashcards
What are pipe blinds?
Slim discs that are placed between pipe flanges.
These are used for LOTO purposes.
What are the two types of pipe blinds mentioned in the module?
- Pancake style
- Spectacle style
These are in-line blinds, and should not be confused with flange blinds, which are used to close off the ends of piping systems.
As it pertains to piping, what are volute blinds?
Blinds that are used to seal the pump volute after removing the pump body.
What is the main disadvantage of pancake blinds vs. spectacle blinds?
Pancake blinds → the flanges have to be spread in order to remove the blind.
Vs. spectacle blinds, where the piping system is designed to accomodate the blind.
With piping blinds, a ____ blind is installed in a piping system that is designed to accomodate the blind, and doesn’t require the flanges to be spread to install it.
Spectacle blinds
How many gaskest are required for:
1. Spectacle blinds?
2. Pancake blinds?
3. Flange blinds?
- Spectacle → 2 gaskets
- Pancake → 2 gaskets
- Flange → 1 gasket
What are three hazards that need to be monitored for when purging a piping system?
- Toxic compounds
- Explosive gases
- Insufficient oxygen
Normal O₂ levels should be around 21% to 22% by volume.
What precautions need to be taken when purging a piping system with CO₂?
CO₂ forms a corrosive substance when mixed with water.
Precautions should be taken if there is a chance that this can happen.
As it pertains the gas detection, OH&S regulations require that you implement procedures to safeguard against what two things?
- Hazards related to the presence of harmful substances.
- Lack of oxygen where workers a present.
What formula is used to convert psi to in.Hg?
Pressure(in.Hg) = Pressure(psi) × 2.036
1 psi = 2.036 in.Hg
This type of gas detector is a hand-held unit that consists of a bellows-type pump and detector tubes.
Sniffer gas detector
Changing the type of detector tube changes the type of gas detected.
How do the detector tubes work in a sniffer type gas detector.
The gas will cause the reactant in the tube to change colour.
The degree of colour change indicates the concentraction levels of the gas.
This type of gas detector contains sensors, controllers and alarm indicators all in one portable unit that is designed to clip to clothing.
Personal gas detectors
These are often called sniffers
What is the %LEL of a gas?
% lower explosive limit
This is the lowest concentration of a gas or vapour that will burn in air.
What needs to be taken into consideration when mounting permanent gas detectors?
The characteristics of the gas
Heavier gas, the sensor will be mounted closer to the ground, while lighter than air results in the sensor being mounted higher up.
What are the common types of gasket joints used in industry?
- Flat face (unconfined)
- Raised face (unconfined)
- Tongue and groove (confined)
- Male and female flange (partial confinement)
- Ring joint (self-confined)
These gasket joints are essential for preventing leakage in various applications, including turbines and compressors.
What is the purpose of a gasket in a sealing application?
To fill the voids or irregularities of the joining faces of the mating parts
Gaskets are softer sealing elements that help achieve a proper seal by accommodating surface imperfections.
True or False: Practical static sealing does not depend on the smoothness of sealing surfaces.
False
Smooth sealing surfaces are crucial for effective sealing and minimizing leakage.
True or false: The ring joint is classified as self-confined.
True
Self-confined joints provide a specific sealing mechanism that does not rely on external pressure.
What machining processes can be involved in achieving sealing surfaces?
- Machining
- Grinding
- Lapping
These processes are vital to ensure the sealing surfaces are sufficiently smooth to prevent leakage.
What is meant by ‘static sealing’?
Forcing a softer sealing element to fill the voids of mating parts
This concept emphasizes the need for proper contact between the gasket and the surfaces to achieve a leak-proof seal.
What is the significance of surface smoothness in gasket applications?
Smoother surfaces seal better.
Smooth surfaces help ensure better sealing and reduce the risk of leakage.
What type of joint is the ‘tongue and groove’ classified as?
Confined
This type of joint provides a more secure fit and minimizes the chance of leakage.
Identify if the following flanges are confined/unconfined/partially confined/self/contained:
- Flat face
- Raised face
- Tongue and groove
- Male and female flange
- Ring joint
- Flat face → unconfined
- Raised face → unconfined
- Tongue and grove → confined
- Male and female flange → partial confinement
- Ring joint → self-confined