Primary manufacturing processes convert raw materials into primary shapes with wide tolerances, poor surface finish, and inadequate integrity. Secondary processes then modify the primary shapes for improved properties, closer tolerances, and better surfaces. Advanced processes can directly create products from raw materials with reduced time and costs. Casting is an example of a primary process that produces parts with intricate shapes but also limitations like dimensional inaccuracies and defects. Patterns are replicas of the desired casting that must account for shrinkage, draft, and machining allowances. Pattern material, type, and size are chosen based on the casting requirements.
Manufacturing Processes
Introduction to manufacturing processes and casting
casting advantages, limitations, pattern materials
types, allowances, pattern color code
Gates, runners and risers, types of core and core making
Moulding sand, types and properties of moulding sand, types of moulding processes,
Investment casting, Gravity and pressure die-casting,
Centrifugal casting, Continuous casting.
Power point presentation about basics of casting technology. Different terms related to casting, do's and don't during casting, properties of casting sand and defects in casting are also discussed.
Manufacturing Processes
Introduction to manufacturing processes and casting
casting advantages, limitations, pattern materials
types, allowances, pattern color code
Gates, runners and risers, types of core and core making
Moulding sand, types and properties of moulding sand, types of moulding processes,
Investment casting, Gravity and pressure die-casting,
Centrifugal casting, Continuous casting.
Power point presentation about basics of casting technology. Different terms related to casting, do's and don't during casting, properties of casting sand and defects in casting are also discussed.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
1. Primary Manufacturing Processes
• Convert raw material to a primary shape/size
• They result in:
• Wide dimensional tolerance
• Inadequate surface finish and surface integrity
• Poor appearance
• Examples
• Casting
• Forming, such as Forging, Rolling, Extrusion, etc.
• Joining, such as Welding, Soldering, etc.
2. Secondary manufacturing processes
• Modify output of primary manufacturing processes
• Input material must have some specific shape and size
• Result in:
• Improved material properties
• Better surface quality and integrity
• Closer dimensional tolerance
• Examples
• Machining
• Surface working, such as Heat Treatment, Coating, etc.
3. Advanced Manufacturing Processes
• Can directly convert raw material into products
• Reduced production time and cost can be reduced
• Various advanced manufacturing processes are:
• Powder Metallurgy (PM)
• Rapid Prototyping (RP) or 3-D Printing
• CNC machines, machining centers, etc.
• Dye Casting, etc.
4. Casting
• Oldest manufacturing process
• Applications:
• Automobile engines
• Turbine blades and housings
• Machine tool structures
• Fly wheel of locomotives
• Jewelry etc.
5. Advantages
• Intricate shapes with complex features can be successfully
• Flexibility of size and weight from jewelry to turbine blades
• Requires simple and inexpensive tools
• High production rate
• Both ferrous or non ferrous materials can be cast
• Low wastage of raw material is very less in the metal casting
6. Limitations of metal casting
• Labor intensive process
• Low dimensional accuracy
• Poor surface finish especially in sand casting
• Possibility of gas defects
• Cast object may have non-uniform mechanical properties due to non-
uniform cooling
8. Pattern
• Replica of the final casting
• Has the similar geometry as the required casting with necessary
modifications like:
• Allowances
• Provision for core prints
• Elimination of fine details
9. Pattern Allowances: Shrinkage Allowance
• Compensates for metal shrinkage
• Shrinkage may be categorized as
• Liquid shrinkage:
• Compensated for by the riser
• Al has most liquid shrinkage
• Solidification shrinkage
• Compensated for by the riser
• Solid shrinkage
• Compensated for by shrinkage allowance
• Brass shows maximum solid shrinkage
• Total shrinkage is maximum for steel
10. Shrinkage Allowances
• Added to linear dimension
• Uniform in all directions unless
constrained
• Grey CI expands on solidification
% V = 2 * (% graphite – 2.8)
11. Pattern Allowances: Draft
• For easy removal of pattern
• Vertical faces are tapered from parting line (0.5 to 2 degrees)
• Varies with design complexity
• Inner details need higher draft allowance
• Hand molding required more draft allowance
12. Draft Allowances
Pattern Material Height of surface (mm) Draft angle (degrees)
External Surface Internal Surface
Wood
Up to 20 3.00 3.00
21 to 50 1.5 2.5
51 to 100 1 1.5
201 to 300 0.75 1
301 to 800 0.5 1
801 to 2000 0.5 0.75
Over 2000 0.35 0.5
Metal and plastic
Up to 20 0.25
21 to 50 1.5 3
51 to 100 1 2
201 to 300 0.75 1
301 to 800 0.5 0.75
801 to 2000 0.5 0.75
Over 2000 0.35 0.5
13. Machining Allowance
• It is required for
• Superior finish
• Dimensional accuracy
• Ranges from 2 to 20 mm depending on
• Casting method used
• Metal cast: Removal of scales in ferrous casts
• Surface finish, dimensional accuracy required
• Complexity of surface details
• May be reduced by proper positioning of parting line
14. Pattern Allowance
• Shake allowance
• Negative allowance
• Provided in sand molds
• Accounts for rapping of pattern
• Distortion allowance
• Provided in long, flat, U or V sections
• When thin sections are connected to thick sections
15. Characteristics of a pattern material
• Easy to work, shape and join
• Light weight
• Strong hard and durable
• Wear and abrasion resistance
• Resistance to corrosion and to other chemical reactions
• Dimensionally stable under wide range of temperature and humidity
• Affordable
16. Pattern Materials
• Choice of pattern material depends on:
• The number of castings to be produced
• Complexity and size of the casting
• Dimension accuracy and surface finish requirements
• Method of casting/mold material
17. Pattern Materials: Wood
• Most commonly used material
• Suitable for large patterns and small number of castings
• Commonly used woods: teak, deodar, mahogany, pine, veneer boards etc.
• Using for making master patterns
• Advantages
• Cheap and easily available
• Light weight
• Easily shaped and may be given a good finish
• Disadvantages
• Has a short life span due to
• Abrasion in sand molds
• Distortion in moist environment: may be controlled
18. Pattern Materials: Metal
• Used for large number of castings and close dimensional tolerance
• Commonly used metals: Al/ Al alloy, brass, white metal, steel, etc.
• Advantages
• Longer life span
• Stronger
• Can be given better finish and tolerances
• Good machinability
• Disadvantages
• Expensive
• Machining requirements add to the cost
• Patterns are very heavy patterns
• Have a tendency to rust in large numbers
19. Plastic
• Includes thermosetting resins, epoxy, PVC, etc.
• Made in sand clay/plaster of paris molds
• Advantages
• Light weight
• Easy formability with a smooth finish
• Dimensional stability: High resistance to wear and corrosion
• Reasonable cost
• Minimal shrinkage
• Disadvantages
• Fragile.
• Not suitable for severe shock conditions like machine molding
20. Other Pattern Materials
• Wax: Used exclusively in investment casting
• Polyurethane foam
• Used for single/ small number of castings
• Light weight and easy formability
21. Choice of Pattern Material
Casting size No. of castings Pattern Material
Small Castings
(up to 600mm)
2000 Hard wood
6000 Al, Plastic
100,000 Cast Iron
Medium Castings
(600 to 1,800 mm)
1,000 Hard wood
3,000 Al, Plastic
Large Castings
(>1,800mm)
200 Soft wood
500 Hard wood metal reinforced
22. Types of patterns
• Single piece pattern
• Split or two piece pattern
• Match plate pattern
• Gated pattern
• Sweep pattern
• Loose piece pattern
• Skeleton pattern
23. Pattern Types
• Single piece Pattern
• Used for simple casts with no with-drawl problems
• Very small scale production
• Used entirely in the drag
• Flat surface forms the parting line
• Gated patterns
• Gating and runner form an integral part of the mold
• Used to make multiple castings in a single mold
• Usually used for making very small castings
• Made of metal
• Used for large production runs
Fig: Single piece pattern
Fig: Gated Pattern
24. Pattern Types
• Split pattern
• Used for making intricate castings when
• Contour makes with-drawl difficult
• Depth is too high
• Dowel pins ensure alignment
• Cope and Drag Pattern
• Gating and risering systems are attached to metal/wooden plates
• Used for heavy castings
• Match plate pattern
• Patterns, gating and risering systems are attached to a single plate
• Pattern is made of metal, usually Al
• Used for
• Large production runs of small castings
• High dimensional accuracy
Fig: Split piece pattern
Fig: Match plate pattern
Fig: Cope and drag pattern
25. Pattern Types
• Sweep pattern
• Used for large castings with rotational symmetry
• 2D pattern results in lower material cost
• Loose piece pattern
• Used when pattern contour does not allow with-drawl
• Loose piece is held by a wire
• Skeleton pattern
• Used for huge castings and short production runs
• It may be hollow for lower cost and weight
• Has two halves
Fig: Loose piece pattern
Fig: Sweep pattern
Fig: Skeletal pattern
