Gasket Material and Gauge Surface Preparation

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According to ASME BPVC I Part PG-60.1, boilers with a maximum allowable working pressure exceeding 400 psi should have how many gage glasses?

No gage glasses

Two gage glasses (correct)

Three gage glasses

One gage glass

What is the purpose of having at least one gage glass in a boiler?

To measure the water density

To measure the steam pressure

To measure the water temperature

To measure the water level (correct)

When are remote water level indicators used according to ASME BPVC I Part PG-60.1.1.1?

Instead of gage glasses (correct)

When the gage glass is malfunctioning

Only for low-pressure boilers

When the boiler is shut down

What is the minimum required distance between the lowest visible water level and the lowest permissible water level in a gage glass, as per ASME BPVC I Part PG-60.1?

2 in. (50 mm) Signup and view all the answers

According to ASME BPVC IV Part HG-603, what is required for each steam heating boiler?

One water gage glass Signup and view all the answers

What is the purpose of the drain valve in the lower fitting of the gauge glass?

To facilitate cleaning by providing an unrestricted drain opening Signup and view all the answers

What is the purpose of the permanent indicator of the lowest permissible water level provided with each boiler?

To ensure the lowest visible part of the gauge glass is at least 1 in. above the lowest permissible water level Signup and view all the answers

What is the purpose of installing drain valves or cocks on the lower gauge glass fitting?

To prevent solid material buildup and facilitate removal Signup and view all the answers

Why are isolating valves placed above and below the gauge glass connections?

To prevent injuries before any maintenance is done Signup and view all the answers

What is the purpose of the metal rods or transparent shield surrounding the gauge glass?

To protect operators from flying glass in case of gauge shatters Signup and view all the answers

What is the minimum distance required for the lowest visible water level in the gauge glass, according to ASME BPVC IV Part HG-603 for steam heating boilers?

25 mm Signup and view all the answers

What is the issue caused by alkalinity and silica depletion at higher temperatures in gauge glasses?

Thinning of tubular glasses below the water line Signup and view all the answers

What should be worn to avoid injury when replacing a gauge glass?

Face shield Signup and view all the answers

For pressures greater than about 3000 kPa, what type of gauge glass is used?

Armored-Type (Flat) Gauge Glass Signup and view all the answers

When should the glass be changed in a transparent gauge glass?

When there is discolouration indicating mica failure Signup and view all the answers

What is the purpose of blowing down the water column and gauge glass in a boiler?

To remove any sediment that may collect Signup and view all the answers

Why would blowing down of the gauge glass be less frequent on large boilers?

To increase the life of the mica Signup and view all the answers

What is used to transfer the optical image of the water level to the control area when it is not readily visible to the operator?

Fiber optic cable or mirrors Signup and view all the answers

What type of indicator is shown in Figure 24 that operates with a large sensitive diaphragm connected to the steam and water space?

Mechanical operation Signup and view all the answers

What are installed to prevent contamination of the indicating liquid in a certain type of remote level indicator?

Dirt traps Signup and view all the answers

What should be done to the gauge surfaces to ensure they are in good condition?

Scrape the gasket off the metal surfaces and polish them perfectly smooth Signup and view all the answers

Why is it important to apply molybdenum disulfide on the contact surfaces of the new glass?

To allow the glass to slip into place easily Signup and view all the answers

What is the purpose of bicolour gauge glasses?

To identify the water level at a distance Signup and view all the answers

What is the purpose of the digital readouts near boiler feed pumps and feedwater bypass valves?

To monitor water levels in different boilers Signup and view all the answers

How can operators be informed of the drum level in boilers located several stories tall?

By installing a hooded mirror to reflect light Signup and view all the answers

How is the information from the reflex-type gauge glasses displayed in the central control room?

On a single computer display Signup and view all the answers

Why does the gauge glass generally indicate a water level lower than the actual level in the boiler drum during normal operation?

Because of a vacuum formed by steam condensation Signup and view all the answers

What must a remote water level indicator display in order to meet the requirements of ASME BPVC I Part PG-60.1.1.1?

Clearly marked minimum water level reference at least 2 in. (50 mm) above the lowest permissible water level Signup and view all the answers

What kind of devices are used as operator aids, in addition to remote water level indicators?

Cameras and loop powered indicators Signup and view all the answers

What is the key requirement for a remote water level indicator to be used according to ASME BPVC I Part PG-60.1.1.2?

Designed and installed to meet the requirements of ASME BPVC I Part PG-60.1.1.2 Signup and view all the answers