Table of Contents
- 1 Why are allowances important in manufacturing?
- 2 What is the importance of pattern in casting?
- 3 What is the importance of allowances in time study?
- 4 What is the function of pattern?
- 5 What are the objectives of time study?
- 6 Why are the pattern allowances in casting important?
- 7 Why are shrinkage allowances important for pattern making?
- 8 When to use distortion allowance in pattern removal?
Why are allowances important in manufacturing?
Allowance is basically the size difference between components that work together. It is important to get the allowance between the axle and the bearing correct so that the axle rotates smoothly and easily without juddering.
What is the importance of pattern in casting?
In casting, a pattern is a replica of the object to be cast, used to prepare the cavity into which molten material will be poured during the casting process.
What are different types of pattern allowances?
Pattern allowances:
- Shrinkage allowance: After solidification of the metal from further cooling (room temp.)
- Draft or taper allowance:
- Distortion allowance:
- Finishing or machining allowance:
- Shaking or rapping allowance:
What is the importance of allowances in time study?
The fundamental purpose of allowances is to add enough time to the basic time of the production in order to enable the average worker to meet the standard while performing at a normal pace.
What is the function of pattern?
Functions of Pattern: (i) A pattern is essential for the production of any metal or alloy casting. (ii) A pattern is used to produce the cavity in the moulding sand for pouring the molten-metal. (iii) A properly manufactured pattern reduces the overall cost of casting.
What is master pattern and its allowance?
A master pattern is created from wax, clay, wood, steel or plastic by either a specialised mould maker or sculpture artists as per final product requirement. These are made considering both wax and casting material shrinkage, hence it’s called, “master pattern” for having double shrinkage allowance.
What are the objectives of time study?
Objectives of Time Study The main objective of time study is to determine by direct observation, the quantum of human work in a specified task and hence to establish the standard time, within which an average worker working at a normal pace should complete the task using a specified method.
Why are the pattern allowances in casting important?
Pattern Allowances In Casting: A pattern is a replica of the casting but has slightly larger dimensions. This change in pattern in casting for various reasons is known as pattern allowance in casting. Example for Pattern Allowances In Casting
What do you call change in pattern allowance?
This change in dimension of casting is known as machining allowance. When casting of very thin surfaces like V Shape, U shape etc. it will distort or damage during pattern removal or during casting. To avoid this problem, a chamber is provided on pattern to compensate distortion during pattern removal.
Why are shrinkage allowances important for pattern making?
The pattern maker’s experience and a little bit of trial are to be used in arriving at the final shrinkages provided on the pattern. The shrinkage allowance is always added to the linear dimensions.
When to use distortion allowance in pattern removal?
When casting of very thin surfaces like V Shape, U shape etc. it will distort or damage during pattern removal or during casting. To avoid this problem, a chamber is provided on pattern to compensate distortion during pattern removal. This change in casting dimension is known as distortion allowance.