Unit 12 Machining Details Objectives Determine the difference

Unit 12 Machining Details

Objectives • • • Determine the difference between a neck and a groove. Determine the sizes of necks and grooves. Identify common types of slots. Identify type and size of a keyway and keyseat. Identify a flat. Determine the difference between a boss and a pad. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Unit 12 • Six Topics can be grouped under two headings: Fastening Group Necks Grooves Slots Assembly Group Keyways Keyseats Flats Last two topics are…. Bosses Pads Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Necks • Recesses in outside diameters • Sometimes called grooves Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Necks • Frequently used when it is necessary to have a threaded diameter assemble flush. • Bear in mind this eliminates the benefits of having the radius. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Necks • Necks are dimensioned using one of three methods… – Width and Depth of the recess – Using a note – Width and diameter of the recess. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Necks Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Necks • If the size of the neck is not important, no dimension is given. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Grooves • Annular (ringlike) recesses • Found on inside and outside diameters Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Grooves • Used for mounting fasteners like snap rings and retaining rings. • Used for installing orings. • Passageways for lubricating oils. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Grooves Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Pulleys • V-groove is a type of groove found on pulleys that use vbelts. This Photo by Unknown Author is licensed under CC BY-SA-NC Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Pulleys help us pull through life • V-groove is a type of groove found on pulleys that use vbelts. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Groovy Shafts • Some shafts may have a machined groove on the end. This Photo by Unknown Author is licensed under CC BY-SA Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

• Some shafts may have a machined groove on the end. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Slots • T-slots – For fastening down devices • Dovetail slots – Used on machine tool slides – Create interlocking assembly – Reciprocating movement Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Slots • T-Slots and Dovetail slots are used to lock turbine blades to rotor. • Turn at high RPM – precise tuning and accurate machining. This Photo by Unknown Author is licensed under CC BY-SA Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Keys…not just for Florida • Keys—secure parts to shafts • Common key types: – Square – Flat – Woodruff Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Keys keep things attached Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Keys are key to smooth operation Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Woodruff Key Sizes • The number of a Woodruff Key identifies its size. • Figuring out the size is like solving a puzzle! Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Woodruff Key Sizes • The last two digits indicate the diameter of the key in 1/8 ths of an inch. • The first two digits provide the width of the key in 1/32 nds of an inch. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Woodruff Key Sizes • #807 indicates the key is 8/32” (or ¼”) wide and 7/8” diameter. • #1013 indicates the key is 10/32” (or 5/16”) wide and 13/8” (or 1 -5/8”) in diameter. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Keyways and Keyseats • Keyway—internal groove in hole • Provides slot for key Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Keyways and Keyseats • Keyseats—external groove on shaft • Provides seating for key Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Flats • A flat is a depression located on a shaft or shank that provides a seat for a setscrew. • The setscrew is used to hold another object in place Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Flats • Many tool shanks and shafts have flats for this purpose. Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.

Bosses and Pads • Boss—cylindrical raised surface • Pad—raised surface shape other than round • Provide smooth surfaces for mating parts Copyright Goodheart-Willcox Co. , Inc. May not be posted to a publicly accessible website.