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2 years ago

What is a rivet and how do tehey work

Engineering

1 answer:

Tresset [83]2 years ago

4 0

Answer:

A rivet is a mechanical fastener composed of a head on one end and a cylindrical stem on another (called the tail) which has the appearance of a metal pin.

When installed the rivet is either drilled, placed or punched into a hole, afterwards the tail is then deformed, holding the rivet in place. When finished the tail has the appearance of a dumbbell shape completing the riveted joint.

You might be interested in

You want to determine whether the race of the defendant has an impact on jury verdicts. You assign participants to watch a trial

Andru [333]

Answer:

The confidence scale represents an ordinal scale of measurement

Explanation:

An ordinal scale or level of measurement is used to measure attributes that can be ranked or ordered, but the interval between the attributes do not have quantitative significance. In this case, the measurement was done on a scale of 1 - 7, with a "1" being; not all that race of defendant has an impact on jury verdicts and a "7" being "very" meaning that race indeed has impact on jury verdicts. Another example can be a survey carried out on the level of customer satisfaction on a particular product, with "1" most dissatisfied and "10 " representing most satisfied. In the first example, it is wrong to say that the difference between 1 being "not at all" and maybe 3 is the same as the difference between 5 and 7 which have different connotations, because the numbers are merely for tagging and not to quantify.

Other levels of measurement include:

1. Nominal: this is the simplest level of measurement and it is simply used to categorize the attributes. Example is taking a survey on gender in the categories of male, female and transgender.

2. Interval: the interval scale is used when the distance between two attributes have meanings but there is no true zero value associated with the scale.

3. Ratio: this combines all the other three levels of measurement and is used to categorize, used to show ranking, has meaningful distances between the attributes and the scale has a true zero point. Example is the measurement of temperature using the celcius scale thermometer, where there is a true zero point at 0°C and the distance between 5°C and 10°C is the same as the distance between 10°C and 15°C.

6 0

3 years ago

A steam power plant operates on an ideal Rankine cycle with two stages of reheat and has a net power output of 120 MW. Steam ent

uysha [10]

Answer:

a) 40.6%

b)72.19kg/s

Explanation:

The Rankine cycle with two reheat stages has 9 stages in total.

The maximum pressure will be at the first inlet stage of the HP turbine which is stage 3. The minimum pressure will be the exit stage of the condenser because the condenser operates under vacuum pressure which is stage 1.

The following assumptions can be made:

1 - Each component in the cycle is analyzed as an open system operating at steady-state.

2 - All of the processes are internally reversible.

3 - The turbine and pump operate adiabatically and are internally reversible, so they are also isentropic.

4 - Condensate exits the condenser as saturated liquid.

5 - The effluent from the HP turbine is a saturated vapor.

6 - No shaft work crosses the system boundary of the boiler or condenser.

7 - Changes in kinetic and potential energies are negligible

a) The thermal efficiency of the cycle is defined as the work of the cycle divided by the total heat input to the system. The stages that have heat input is stages 2-3, 4-5, 6-7.

For stage 2:

s₁=s₂ assuming isentropic

$s_1=0.4762 @ P_1=15MPa$

enthalpy will be a compressed liquid so after interpolation

$h_2=97.93+(0.4762-0.2932)((180.77-97.93)/(0.5666-0.2932))=153.38kJ/kg$

For stage 3:

Superheated steam @ T=500⁰C and P=15MPa

$h_3=3310.8kJ/kg$

Stage 4:

superheated vapor

P=5MPa

s₃=s₄=6.3480 kJ/kg, we must use interpolation to find h₄

$h_4=2925.7-(6.348-6.2111)((3069.3-2925.7)/(6.4516-6.2111))=3007.44kJ/kg$

Stage 5:

Superheated steam @ T=500⁰C and P₄=P₅=5 MPa

$h_5=3434.7kJ/kg$

Stage 6:

Superheated steam at P₆= 1MPa

s₅=s₆

$s_6=6.9781$

We find h₆ using interpolation from the steam tables:

$h_6=2943.1-(6.9781-6.9265)((3051.6-2943.1)/(7.1246-6.9265))=2970.67kJ/kg$

Stage 7:

P₇=P₆=1MPa

T=500⁰C superheated steam

$h_7=3479.1kJ/kg$

The heat into the cycle is:

$=(h_3-h_2)+(h_5-h_4)+(h_7-h_6)$

$=(3310.8-153.38)+(3434.7-3007.44)+(3479.1-2970.67)=4108.74kJ/kg$

We can determine the work out by the condenser from stage 9 to stage 1:

Stage 1:

saturated liquid P=5kPa

$h_1=137.75kJ/kg$

Stage 9:

We assume that its a saturated liquid with quality of 1 at 5kPa and

s₇=s₉ and after interpolation

$h_9=2568.53kj/kgK$

Qout = [/tex]2568.53-137.75=2430.79kJ/kg[/tex]

The thermal efficiency can be written in terms of qin and qout:

$n=1-(q_o/q_i)=1-2430.79/4093.11=0.4061$

Efficiency of 40.61%

The mass flow rate can be calculated from the Wnet:

$W_n=W_t-W_p$

Work of the turbines minus the work of the pumps:

$W_n=m((h_3-h_4)+(h_5-h_6)+(h_7-h_9)-(h_1-h_2)$

$120000=m(1662.33)$

$m=72.19$

mass flow rate of steam is 72.19 kg/s

7 0

3 years ago

Which statements describe how the Fed responds to high inflation? Check all that apply.

Sveta_85 [38]

Answer:
• it charges banks more interest
• it sells more securities
• it decreases the money supply

In response to high inflation, the Fed charges banks more interests and pays the banks less interests. It also sells not securities.

8 0

2 years ago

The penalty for littering 15 lb or less is _____.<br> A. $25<br> B. $50<br> C. $100<br> D. $150

Marina CMI [18]

Answer:

D the closest

Explanation:

i looked it up and 8t says 200

5 0

3 years ago

_______ is a material property that pertains to local resistance to plastic deformation, such as scratching or denting. It is of

Readme [11.4K]

Answer: hardness

Explanation:

Hardness is a measure of a material's ability to resist plastic deformation. In other words, it is a measure of how resistant material is to denting or scratching. Diamond, for example, is a very hard material. It is extremely difficult to dent or scratch a diamond. In contrast, it is very easy to scratch or dent most plastics.

7 0

3 years ago