CHAPTER 2
LAYOUT AND BENCHWORK
CHAPTER LEARNING OBJECTIVES
Upon completing this chapter, you should be able to do the following:
Describe the process used to extract data from blueprints.
Describe the procedures used to draft working drawings for parts
manufacture and alteration.
Explain surface characteristics of metal.
Explain how to determine surface finish quality.
Explain layout work.
Explain the procedure used to lay out valve flange bolt holes.
State the process used to hand scrape and blue parts and surfaces for flatness
and fit.
Explain filing operation.
Explain the setup and operation of pressure.
Explain the setup and operation of oxyacetylene equipment.
Explain the use of helicoils.
As an MR, you will repair or help repair many
As with any shop equipment you must observe all
types of equipment used on ships. You will make
posted safety precautions. Review your equipment
replacement parts, disassemble and assemble
operators manual for safety precaustions and any
equipment, make layouts of parts to be machined, and
chapters of Navy Occupational Safety and Health
do precision work to lit mating parts of equipment. This
(NAVOSH) Program Manual for Forces Afloat
is known as benchwork and it includes practically all
(OPNAV) Instruction 5100.19B that pertain to the
repair work other than actual machining.
equipment.
This chapter contains information that you need
to make effective repairs. Read Blueprint Reading
LIMITS OF ACCURACY
and Sketching, NAVEDTRA 10077-F1, for additional
information on working drawings. Other sources of
You must work within the limits of accuracy
information that you should study for details on
specified on the drawing. A clear understanding of
specific equipment include the Naval Ships' Techical
TOLERANCE and ALLOWANCE will help you to
Manual, the manufacturers technical manuals, and
avoid small, but potentially dangerous, errors. These
the training manuals for the equipment you are
terms may seem closely related, but each has a very
working on.
precise meaning and application. We'll point out the
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