A tool that has a single point for cutting purpose is called single point cutting tool. It is generally used in the lathe machine, shaper machine etc. It is used to remove the materials from the workpiece.
Thread fastener, Computer Aided Machine Drawing (CAMD) of VTU Syllabus prepared by Hareesha N Gowda, Asst. Prof, Dayananda Sagar College of Engg, Blore. Please write to hareeshang@gmail.com for suggestions and criticisms.
A tool that has a single point for cutting purpose is called single point cutting tool. It is generally used in the lathe machine, shaper machine etc. It is used to remove the materials from the workpiece.
Thread fastener, Computer Aided Machine Drawing (CAMD) of VTU Syllabus prepared by Hareesha N Gowda, Asst. Prof, Dayananda Sagar College of Engg, Blore. Please write to hareeshang@gmail.com for suggestions and criticisms.
chapter-5 Limits, classification Fits and Tolerances.SHITALUDAGAVE2
It is impossible to produce a part to an exact size or basic size, some
variations, known as tolerances, need to be allowed.
The permissible level of tolerance depends on the functional requirements, which cannot be compromised
The limit fit tolerance refers to the acceptable degree of variation allowed in a part's dimensions or the permissible difference between the minimum and maximum sizes of mating parts in engineering and manufacturing. This system ensures that parts fit together properly while accounting for unavoidable variations in the manufacturing process.
The tolerance consists of two main components:
Limits: These are the extreme values (upper and lower bounds) within which the actual dimension of a part must fall.
Fits: The relationship between the parts based on the prescribed tolerance. Fits can be categorized into various types, such as clearance fit, interference fit, and transition fit, based on the allowances for the difference between the mating parts.
The ANSI (American National Standards Institute) and ISO (International Organization for Standardization) often provide standard charts and tables that detail various limit fit tolerance classes. These classes specify the allowances for different fits to ensure proper functionality while allowing for ease of assembly or providing a snug fit, depending on the application.
Selecting the appropriate limit fit tolerance depends on the specific requirements of the application, considering factors like function, material, environmental conditions, and manufacturing capabilities. This ensures that parts fit together with the required precision, avoiding issues like parts being too loose or too tight.
When specifying a limit fit tolerance for manufacturing or engineering purposes, it's essential to consider:
Design requirements: What function does the part need to fulfill?
Material properties: Different materials expand, contract, or behave differently under varying conditions.
Environmental factors: Temperature, humidity, and other external conditions may affect the parts' dimensions.
Manufacturing processes: The methods used for manufacturing can influence the achievable tolerance.
Ultimately, the right limit fit tolerance is a balance between functionality, ease of assembly, and ensuring the required performance of the final product. Engineering standards, charts, and tables provided by organizations like ANSI and ISO offer guidance in selecting appropriate tolerances for specific applications.
in this ppt pdf the various types of fitting has explained. and how the different gauges like plug and ring gauge check holes and shaft are also explained.
An introduction to the cryptocurrency investment platform Binance Savings.Any kyc Account
Learn how to use Binance Savings to expand your bitcoin holdings. Discover how to maximize your earnings on one of the most reliable cryptocurrency exchange platforms, as well as how to earn interest on your cryptocurrency holdings and the various savings choices available.
Premium MEAN Stack Development Solutions for Modern BusinessesSynapseIndia
Stay ahead of the curve with our premium MEAN Stack Development Solutions. Our expert developers utilize MongoDB, Express.js, AngularJS, and Node.js to create modern and responsive web applications. Trust us for cutting-edge solutions that drive your business growth and success.
Know more: https://www.synapseindia.com/technology/mean-stack-development-company.html
Event Report - SAP Sapphire 2024 Orlando - lots of innovation and old challengesHolger Mueller
Holger Mueller of Constellation Research shares his key takeaways from SAP's Sapphire confernece, held in Orlando, June 3rd till 5th 2024, in the Orange Convention Center.
Buy Verified PayPal Account | Buy Google 5 Star Reviewsusawebmarket
Buy Verified PayPal Account
Looking to buy verified PayPal accounts? Discover 7 expert tips for safely purchasing a verified PayPal account in 2024. Ensure security and reliability for your transactions.
PayPal Services Features-
🟢 Email Access
🟢 Bank Added
🟢 Card Verified
🟢 Full SSN Provided
🟢 Phone Number Access
🟢 Driving License Copy
🟢 Fasted Delivery
Client Satisfaction is Our First priority. Our services is very appropriate to buy. We assume that the first-rate way to purchase our offerings is to order on the website. If you have any worry in our cooperation usually You can order us on Skype or Telegram.
24/7 Hours Reply/Please Contact
usawebmarketEmail: support@usawebmarket.com
Skype: usawebmarket
Telegram: @usawebmarket
WhatsApp: +1(218) 203-5951
USA WEB MARKET is the Best Verified PayPal, Payoneer, Cash App, Skrill, Neteller, Stripe Account and SEO, SMM Service provider.100%Satisfection granted.100% replacement Granted.
Recruiting in the Digital Age: A Social Media MasterclassLuanWise
In this masterclass, presented at the Global HR Summit on 5th June 2024, Luan Wise explored the essential features of social media platforms that support talent acquisition, including LinkedIn, Facebook, Instagram, X (formerly Twitter) and TikTok.
LA HUG - Video Testimonials with Chynna Morgan - June 2024Lital Barkan
Have you ever heard that user-generated content or video testimonials can take your brand to the next level? We will explore how you can effectively use video testimonials to leverage and boost your sales, content strategy, and increase your CRM data.🤯
We will dig deeper into:
1. How to capture video testimonials that convert from your audience 🎥
2. How to leverage your testimonials to boost your sales 💲
3. How you can capture more CRM data to understand your audience better through video testimonials. 📊
Putting the SPARK into Virtual Training.pptxCynthia Clay
This 60-minute webinar, sponsored by Adobe, was delivered for the Training Mag Network. It explored the five elements of SPARK: Storytelling, Purpose, Action, Relationships, and Kudos. Knowing how to tell a well-structured story is key to building long-term memory. Stating a clear purpose that doesn't take away from the discovery learning process is critical. Ensuring that people move from theory to practical application is imperative. Creating strong social learning is the key to commitment and engagement. Validating and affirming participants' comments is the way to create a positive learning environment.
2. Fig. 1.1 Graphical Illustration of Fits and Tolerances
ILLUSTRATION OF BASIC SIZE DEVIATIONS,
LIMITS AND TOLERANCES
3. LIMITS
Actual machine size - between the maximum
and minimum limits
MAXIMUM LIMIT
Maximum permissible machine size corresponding to basic
size.
Fig. 1.1, Ø 30 mm is = Ø 30 + 0.035 = Ø 30. 035 mm.
Basic size Maximum limit
MINIMUM LIMIT
Minimum allowable machine size corresponding to basic
size.
In Fig. 1.1, Ø 30 mm is = Ø 30 - 0.215 = Ø 29. 785 mm.
Basic size Minimum limit
4. TOLERANCE
The difference between the maximum and minimum limits
of a size is tolerance.
In Fig. 1.1 the tolerance is = Ø 30.035 - Ø 29.785 = 0.25m.
Max. limit Min. limit Tolerance
DEVIATION
(Actual, or maximum, or minimum) – (Basic size).
UPPER DEVIATION - (Maximum limit) – (Basic size)
In Fig.1.1, the upper deviation is = Ø 30.035 - Ø 30
= 0.035 mm.
5. LOWER DEVIATION - (Minimum limit) – (Basic size)
In Fig. 1.1, the lower deviation is = Ø 29.785 - Ø 30
= - 0.215 mm.
ACTUAL DEVIATION - (Actual measured size) – (Basic size)
In Fig. 1.1, the actual deviation = Ø 29.925 - Ø 30
= - 0.075 mm.
ZERO LINE
• A straight line drawn for the basic size is called zero line.
• Upper and lower deviation are referred to zero line.
• Zero line is drawn horizontally.
• Above zero line - positive deviations.
• Below zero line - negative deviations.
6. TOLERANCE ZONE
The zone bounded by the upper and lower limits of the
basic size.
In Fig. 1.1, tolerance zone is shown by hatched line.
FITS
• The relationship between the mating surfaces of
the parts,because of the difference in dimensions
is
called fit.
• Thus fit has a characteristic effect on the
performance of mating parts.
• Example: width of the slot & the thickness of the
key.
7. CLEARANCE
(Hole dimension) – (Dimension of shaft that fit to it).
Maximum - hole size is maximum and the shaft size is
minimum.
Minimum - shaft size is maximum and the hole size is
minimum.
CLASSIFICATION OF FITS
Clearance fit
Interference fit
Transition fit
8. A
B
Fig. 1.2 Clearance Fit
Min hole – Max Shaft = + ve – clearance fit.
Fit with positive clearance between the hole and the shaft.
CLEARANCE FIT
9. INTERFERENCE FIT
Fit with negative clearance between the hole and the shaft.
Fig. 1.3 Interference Fit
Max hole – Min Shaft = - ve – interferance fit
10. TRANSITION FIT
Fit established when the dimensions of the hole are
such that there exists either a positive clearance or a
negative clearance when the shaft is fitted into the hole.
B
12. TRANSITION FITS AND INTERFERENCE FITS
Combination of
Hole and Shaft
Quality of Fit Typical uses
H6 j5 fine
Clearance
transition
Very small clearance is obtained - used for fits where a
slight interference is permissible - coupling spigots and
recesses, gear rings clamped to steel hubs.
H7 j6 normal
H8 j7 coarse
H6 k5 fine
True
transition
Fits averaging no clearance where slight interference can be
tolerated , with the object of eliminating vibration - ball
bearings races of light duty.
H7 k6 normal
H8 k7 coarse
H6 m5 fine
Interference
transition
Fits averaging slight interference - used for ball bearing
races of medium duty.
H7 m6 normal
H8 m7 coarse
H6 p5 fine
Press fit
Light press fit for nonferrous parts which can be dismantled
when required-bearing bushes-press fit for steel, cast iron
or brass to steel assemblies- bush in a gear.H7 p6 normal
H6 r5 fine
Drive fit Medium drive fit for ferrous parts and light drive fit for
non-ferrous parts that can be dismantled.H7 r6 normal
H6 s5 fine
Drive fit
Permanent or semi permanent assemblies of steel and cast
iron with considerable gripping force- collars pressed on to
shafts, valve seatings etc. For light alloys this gives a press
fit.
H7 s6 normal
H6 u5 fine
Force or
shrink fit
High interference fit a thorough investigation into the
degree of grip and the stresses in the part must be made.H7 u6 normal
13. SYSTEMS OF FITS
HOLE BASIS SYSTEM: the hole is constant in
diameter and various types of fits are obtained by
suitably varying the limits of the shaft.
SHAFT BASIS SYSTEM: the shaft is constant in
diameter and various types of fits are obtained by
suitably varying the limits of the hole.
14. Fig. 1.5 Hole Basis System
Clearance Fit
B
Interference Fit
C
HOLE BASIS SYSTEM
Single hole, whose lower deviation is zero.
Minimum limit of the hole will be equal to its basic size.
15. Grades of
Holes
MANUFACTURING PROCESS USED
H5 Fine Boring, Fine Grinding, Honing
H6 Fine Boring, Honing, Hand Reaming
H7 Int. Grinding, Broaching, Reaming
H8 Boring, Machine Reaming
H9 Boring & Reaming
H10
Not for diameter fits; used for milled widths,
drilled holes
H11
Not used in fits; punching, coarse drilling drawn
recesses
16. HOLE BASIS SYSTEM - Design Example
Requirement
Hole basic size - 20 mm diameter.
Clearance of - 0.100 mm.
Hole tolerance - 0.025 mm.
Shaft tolerance - 0.050 mm.
Minimum limit of the hole is Ø 20 mm.
Maximum limit of the shaft = Lower limit of the hole –
Minimum clearance
= Ø 19.900 mm
Design
17. Minimum limit of the shaft = Maximum limit of the shaft –
Tolerance on the shaft.
= Ø 19. 850 mm.
Shaft
Max. limit = Ø 19.900 mm.
Min. limit = Ø 19. 850 mm.
Maximum limit of the hole = Maximum limit of the hole +
Tolerance on the hole.
= Ø 20. 025 mm.
Hole
Max. limit = Ø 20.025 m.
Min. limit = Ø 20. 000 mm.
18. Why the Hole Basis System is Preferred?
Holes are produced by drilling, boring, reaming,
broaching, etc.,
Shafts are either turned or ground.
Shaft basis system - Holes of different sizes are required,
(requires tools of different types and
sizes).
Hole basis system - Only one tool is required, to
produce the hole and the shaft can
be machined to any desired size.
19. SYSTEMS OF TOLERANCING
1. UNILATERAL SYSTEM
• Deviations are allowed in only one direction from the
basic size.
• The deviation in the other direction is zero.
• Hence, either the maximum limit or the minimum
limit will be equal to the basic size.
• Deviations are allowed in both the directions from
the basic size.
• The deviations are allowed in both the directions.
• One of the limits - above the basic size.
• Other limits - below the basic size.
2. BILATERAL SYSTEM
27. REFERENCE
1. Gopalakrishna K R, “Machine Drawing”, Tenth
Edition, Bangalore, 1996.
2. Faculty of Mechanical Engineering, PSG College of
Technology, “Design Data Book”, Coimbatore, 1993.
3. ASME Y 14.5M- 1994, “Dimensioning and
Tolerancing”, ASME, New York, 1995.