Hull Maintenance Technician Flashcards Overview

Four basic tasks of a Hull Maintenance Technician

Welding, pipefitting, metal fabrication, and plumbing.

Function of the QA program

To ensure maintenance is performed correctly and safely the first time.

QA Form 9

Verification of maintenance procedure and results.

Confined space

An area not designed for continuous occupancy with limited entry and exit.

Importance of ventilation in welding operations

To remove toxic fumes and provide fresh air.

Straight edge in layout

To draw or scribe straight lines on metal surfaces.

Function of a combination square

To measure and mark 45° and 90° angles.

Type of flame used for welding steel with an oxyacetylene torch

A neutral flame.

Purpose of flux in brazing

To clean and protect metal surfaces from oxidation.

Difference between soldering and brazing

Soldering occurs below 840°F, brazing above 840°F.

How pipe is measured

By its nominal pipe size and wall thickness (schedule).

Purpose of a pipe threader

To cut threads on the ends of pipes for fitting.

Two most common welding positions

Flat and horizontal.

Essential safety gear during grinding

Face shield, safety glasses, gloves, and hearing protection.

Cause of undercut in a weld

Improper technique or excessive welding current.

How to test a weld visually

Check for uniformity, cracks, porosity, and penetration.

Fillet weld

A weld that joins two surfaces at a right angle.

Butt joint

A joint where two pieces are placed end-to-end in the same plane.

Hot work permit

Authorization for performing welding or burning in hazardous areas.

Level I material

Materials requiring traceability due to safety-critical applications.

Role of a QA Inspector

To verify compliance with procedures and document quality checks.

Pipe hanger

A device used to support and secure piping systems.

Tool used to remove slag after arc welding

A chipping hammer.

Layout tool that marks circles or arcs

A divider or trammel.

Purpose of a scribe

To mark lines on metal surfaces before cutting.

Advantage of TIG welding

Purging

To prevent oxidation on the inside of the pipe.

QA Form 3

What form logs QA inspections on material condition.

Calibration of tools

To ensure accurate measurements and compliance with standards.

Pressure system welding preparation

Check procedures, get QA approval, and ensure system is isolated.

Root pass in welding

The first pass that fuses the joint from the root.

Weep hole

To allow fluids to drain and prevent corrosion.

Pipe lagging

For insulation to reduce heat loss and protect personnel.

Male and female pipe threads

Male threads are external; female threads are internal.

Die stock

To hold and guide the die for threading.

Tack welding

It holds components in alignment before final welding.

Thread pitch gauge

What tool is used to check thread pitch.

Eccentric reducer

To change pipe diameter while maintaining bottom-of-pipe alignment.

Pipe flanges

To connect pipes and allow disassembly.

Types of welding currents

DCEN, DCEP, and AC.

Major types of pipe joints

Threaded, flanged, soldered, brazed, and welded.

Expansion loop

A bend in pipe to absorb thermal expansion.

Schedule 40 vs Schedule 80 pipe

Schedule 80 has thicker walls.

Thread sealant

To prevent leaks in threaded connections.

Reducer vs bushing

Reducers change pipe size; bushings are threaded reducers.

Welding position 1G

Flat position for groove welds.

Back purging

To protect the backside of a weld from oxidation.

Pipe roundness check tool

A caliper or Pi tape.

Feeler gauge

To measure gap widths.

Cleanliness inspection

That the system is free of debris before closing.

Torch tip size

Based on metal thickness and type of welding.

Recommended PSI for oxygen in oxy-fuel cutting

Typically 20-25 PSI.

Acetylene regulator function

To control gas flow to the torch.