Boiler Pressure Gauge and ASME BPVC I

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Why must each steam boiler be equipped with an accurate pressure gauge?

To regulate the pressure in the boiler

To indicate the water level in the boiler

To monitor the pressure in the boiler (correct)

To measure the temperature of the boiler

According to ASME BPVC I Part PG-60.6.1, how should the dial of the pressure gauge be graduated?

To 1 ½ times the pressure at which the safety valve is set

To half the pressure at which the safety valve is set

To exactly match the safety valve setting

To approximately double the pressure at which the safety valve is set (correct)

What does it mean when the pressure gauge is calibrated to double the safety valve setting?

The boiler is at a dangerous pressure level

The boiler is not producing enough steam

The operator can tell at a distance if the boiler is at its normal operating pressure (correct)

The safety valve will not function properly

Why should the pressure gauge be installed so that it shall at all times indicate the pressure in the boiler?

To ensure safe operation and monitoring of pressure Signup and view all the answers

What is the primary purpose of a bourdon tube gauge in a steam boiler?

To accurately measure and indicate internal pressure of the boiler Signup and view all the answers

What is important for a pressure gauge to be suitable for use during a hydrostatic test?

To indicate twice the maximum allowable working pressure of the boiler Signup and view all the answers

What is one reason for graduating the dial of a pressure gauge to double the safety valve setting?

To ensure accuracy when reading mid-span Signup and view all the answers

What is the purpose of connecting the pressure gauge to the steam space or water column?

To prevent the pressure gauge from being affected by the boiler’s hydrostatic head Signup and view all the answers

Why is a shutoff valve placed in the gauge connection adjacent to the gauge?

To facilitate the installation of a master test pressure gauge Signup and view all the answers

What is the function of a pigtail siphon or an equivalent device in relation to a pressure gauge?

To trap condensate and prevent steam from entering the gauge tube Signup and view all the answers

Why must piping or siphons for steam boilers have specific minimum dimensions?

To allow for easy inspection and cleaning on a regular basis Signup and view all the answers

What is the purpose of installing a tee with an NPS ¼ plug between the siphon and boiler pressure gauge?

To facilitate inspection and cleaning of the pressure piping Signup and view all the answers

Why should siphons be filled with distilled water prior to installation?

To protect the pressure-sensing device from steam as soon as it is admitted to the siphon Signup and view all the answers

What does ASME BPVC IV Part HG-602 state about the scale on the dial of a steam boiler gauge?

It should be graduated to not less than 200 kPa (30 psi) nor more than 414 kPa (60 psi) Signup and view all the answers

What is an important reason for installing an inspector gauge connection on low-pressure boilers, according to ASME BPVC IV Part HG-602?

To allow verification of the reading of the boiler gauge during operation Signup and view all the answers

Study Notes

Pressure Gauge Importance

Each steam boiler must have an accurate pressure gauge to monitor pressure within the boiler.
An accurate reading is crucial for safe operation and to prevent accidents.

Pressure Gauge Dial Graduation

According to ASME BPVC I Part PG-60.6.1, the dial of the pressure gauge must be graduated in increments of no more than 10% of the full-scale range.

Gauge Calibration

Calibrating the pressure gauge to double the safety valve setting provides a margin of safety.
It allows for early detection of pressure increases exceeding the safety valve setting, promoting timely intervention.

Pressure Gauge Installation

The pressure gauge should be installed in a location that allows it to constantly indicate the pressure inside the boiler.

Bourdon Tube Gauge Function

The primary function of a bourdon tube gauge in a steam boiler is to accurately measure the pressure of steam inside the boiler.

Pressure Gauge Suitability for Hydrostatic Testing

For hydrostatic testing, the pressure gauge should be suitable for the pressure range of the test and be capable of accurately measuring the maximum pressure applied during the test.

Gauge Dial Graduation Rationale

Graduating the pressure gauge dial to double the safety valve setting provides a visual indication of the pressure exceeding the safety valve limit.
It enables prompt action before the safety valve activates, ensuring control over potentially dangerous pressure increases.

Gauge Connection Purpose

Connecting the pressure gauge to the steam space or water column allows for accurate measurement of the internal boiler pressure.

Shutoff Valve Function

A shutoff valve near the pressure gauge, located in the gauge connection, provides a means to isolate the gauge during maintenance or repairs without affecting boiler operation.

Pigtail Siphon Function

A pigtail siphon or an equivalent device helps prevent condensate from entering the pressure gauge, ensuring accurate pressure measurement.

Piping Dimension Requirements

Piping or siphons connected to steam boilers have specific minimum dimensions to ensure proper flow and prevent clogging caused by condensate.

Tee with Plug Purpose

Installing a tee with an NPS ¼ plug between the siphon and the boiler pressure gauge allows for easy clearing of any accumulated condensate in the siphon by removing the plug.

Siphon Filling Requirement

Filling siphons with distilled water prior to installation minimizes potential corrosion and ensures accurate pressure readings by eliminating air or other gases within the siphon.

Gauge Dial Scale

ASME BPVC IV Part HG-602 specifies that the scale on the dial of a steam boiler gauge should be clear, legible, and marked with appropriate increments.

Inspector Gauge Connection Importance

ASME BPVC IV Part HG-602 recommends installing an inspector gauge connection on low-pressure boilers for easy inspection by authorized personnel.
It allows for precise pressure reading verification during inspections without requiring any modifications to the main boiler pressure gauge connection.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge about steam boiler pressure gauges, their importance, and the relevant ASME BPVC I Part PG-60.6.1 standard.