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3 years ago

5

The gradual and uniform cooling of glass that has been heated in order to relieve random internal stresses is... Group of answer

choices annealing tempering quenching heat treating

1 answer:

kirill115 [55]3 years ago

7 0

Answer: Annealing

Explanation:

In the manufacturing of glass, Processes such as expansion when glass heats and cooling when it contracts are involved. These build up random internal stresses which can cause cracks and breakage when finally cooled at room temperature. To relieve these stresses, Annealing is carried out on glass during the manufacturing process.

Annealing is the process whereby the temperature during the process of the manufacturing of glass is reduced and maintained at a uniform rate so that it undergoes a gradual cooling process. so as to make the glass tough and reduce internal stress.

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Identify the phase of the design process illustrated in the following scenario, and justify its importance. Kristin has recently

zaharov [31]

Answer:

The design process is at the verify phase of Design for Six Sigma

Explanation:

In designing for Six Sigma, DFSS, is a product or process design methodology of which the goal is the detailed identification of the customer business needs by using measurements tools such as statistical data, and incorporating the identified need into the created product which in this case is the hydraulic robot Kristin Designed

Implementation of DFSS follows a number of stages that are based on the DMAIC (Define - Measure - Analyze - Improve) projects such as the DMADV which stand for define - measure - analyze - verify

Therefore, since Kristin is currently ensuring that the robot is working correctly and meeting the needs of her client the design process is at the verify phase.

5 0

3 years ago

A ball bearing has been selected with the bore size specified in the catolog as 35.000 mm to 35.020 mm. Specify appropriate mini

Fofino [41]

Answer:

the minimum shaft diameter is 35.026 mm

the maximum shaft diameter is 35.042mm

Explanation:

Given data;

D-maximum = 35.020mm and d-minimum = 35.000mm

we have to go through Tables "Descriptions of preferred Fits using the Basic Hole System" so from the table, locational interference fits H7/p6

so From table, Selection of International Trade Grades metric series

the grade tolerance are;

ΔD = IT7(0.025 mm)

Δd = IT6(0.016 mm)

Also from Table "Fundamental Deviations for Shafts" metric series

Sf = 0.026

so

D-maximum

Dmax = d + Sf + Δd

we substitute

Dmax = 35 + 0.026 + 0.016

Dmax = 35.042 mm

therefore the maximum diameter of shaft is 35.042mm

d-minimum

Dmin = d + Sf

Dmin = 35 + 0.026

Dmin = 35.026 mm

therefore the minimum diameter of shaft is 35.026 mm

8 0

3 years ago

Select the correct answer.

boyakko [2]

I think the answer is b

6 0

3 years ago

Read 2 more answers

Lydia is the CEO for a large pharmaceutical manufacturer. Her company is in the final stages of FDA

weqwewe [10]

OSHA inspections are generally unannounced. In fact, except in four exceptional circumstances when advance notice may be given.

It is a criminal offense for any person to give unauthorized advance notice of an OSHA inspection.

5 0

3 years ago

Air at 400kPa, 970 K enters a turbine operating at steady state and exits at 100 kPa, 670 K. Heat transfer from the turbine occu

Sonja [21]

Answer:

a

The rate of work developed is $\frac{\r W}{\r m}= 300kJ/kg$

b

The rate of entropy produced within the turbine is $\frac{\sigma}{\r m}= 0.0861kJ/kg \cdot K$

Explanation:

From the question we are told

The rate at which heat is transferred is $\frac{\r Q}{\r m } = - 30KJ/kg$

the negative sign because the heat is transferred from the turbine

The specific heat capacity of air is $c_p = 1.1KJ/kg \cdot K$

The inlet temperature is $T_1 = 970K$

The outlet temperature is $T_2 = 670K$

The pressure at the inlet of the turbine is $p_1 = 400 kPa$

The pressure at the exist of the turbine is $p_2 = 100kPa$

The temperature at outer surface is $T_s = 315K$

The individual gas constant of air R with a constant value $R = 0.287kJ/kg \cdot K$

The general equation for the turbine operating at steady state is \

$\r Q - \r W + \r m (h_1 - h_2) = 0$

h is the enthalpy of the turbine and it is mathematically represented as

$h = c_p T$

The above equation becomes

$\r Q - \r W + \r m c_p(T_1 - T_2) = 0$

$\frac{\r W}{\r m} = \frac{\r Q}{\r m} + c_p (T_1 -T_2)$

Where $\r Q$ is the heat transfer from the turbine

$\r W$ is the work output from the turbine

$\r m$ is the mass flow rate of air

$\frac{\r W}{\r m}$ is the rate of work developed

Substituting values

$\frac{\r W}{\r m} = (-30)+1.1(970-670)$

$\frac{\r W}{\r m}= 300kJ/kg$

The general balance equation for an entropy rate is represented mathematically as

$\frac{\r Q}{T_s} + \r m (s_1 -s_2) + \sigma = 0$

=> $\frac{\sigma}{\r m} = - \frac{\r Q}{\r m T_s} + (s_1 -s_2)$

generally $(s_1 -s_2) = \Delta s = c_p\ ln[\frac{T_2}{T_1} ] + R \ ln[\frac{v_2}{v_1} ]$

substituting for $(s_1 -s_2)$

$\frac{\sigma}{\r m} = \frac{-\r Q}{\r m} * \frac{1}{T_s} + c_p\ ln[\frac{T_2}{T_1} ] - R \ ln[\frac{p_2}{p_1} ]$

Where $\frac{\sigma}{\r m}$ is the rate of entropy produced within the turbine

substituting values

$\frac{\sigma}{\r m} = - (-30) * \frac{1}{315} + 1.1 * ln\frac{670}{970} - 0.287 * ln [\frac{100kPa}{400kPa} ]$

$\frac{\sigma}{\r m}= 0.0861kJ/kg \cdot K$

5 0

4 years ago