Skip to main content
12 votes
Accepted

Block diagram vs flow chart?

Use Google's define:<item to look up> feature. block diagram noun: block diagram; plural noun: block diagrams a diagram showing in schematic form the ...
Transistor's user avatar
  • 10.9k
10 votes

Do I need a pressure relief/safety valve if my pump can't exceed the rated system pressure?

Not a plumbing engineer, but: What about thermal expansion? You reach a dead end, pump stops. Pumps often have a checkvalve that prevents backflow, so you have now created a pressurized container. ...
Thomas's user avatar
  • 109
9 votes

What is the correct pipe size for a 2inch pipe?

As of the 2013 edition of ASME B16.5, the scope section explains: This Standard states values in both SI (Metric) and U.S. Customary units. As an exception, diameter of bolts and flange bolt ...
Ethan48's user avatar
  • 4,541
7 votes
Accepted

Does every engineering design needs to have a complete theoretical backing or may experimental data suffice?

Are any designs based solely on data from trial and error used in critical mainstream engineering? Usually not. And the reason is that trial and error is expensive and time consuming. As engineers, ...
Daniel K's user avatar
  • 2,646
6 votes
Accepted

What is the correct pipe size for a 2inch pipe?

I would guess that the discrepancy is down to rounding fractional inch sizes to decimal inches ie 2.38 is not exactly 2 3/8" Note that 2.375 (two and three quarter eighth inches) is 60.325mm
Chris Johns's user avatar
  • 15.2k
4 votes
Accepted

Real world applications where one would use a force function in PLC programming?

A "force" in a PLC is the act of forcing a memory bit on or off from the PLC programming software. It is used exclusively for testing. Forcing a bit on or off over-rides all other PLC logic. You can ...
ericnutsch's user avatar
  • 8,181
4 votes

Do I need a pressure relief/safety valve if my pump can't exceed the rated system pressure?

Certainly not all piping systems need relief valves. The specifics of the application matter. Relief valves typically protect vessels that can store significant energy and release it violently at ...
Tiger Guy's user avatar
  • 6,969
3 votes

Block diagram vs flow chart?

The ISO EN 10628-1 has this example for a basic flow chart (which block diagram may also refer to): The blocks can be unit operations, processes, or parts of a plant, the lines can be material or ...
mart's user avatar
  • 4,791
3 votes
Accepted

Modelling gas desorption from a still solution (e.g. a beer)

In perfectly stagnate gas systems, transport of a component through a gas collapses to diffusion of the component through the gas. In this case, $k_L a \propto (D / \delta)^n$ where $D$ is diffusion ...
Jeffrey J Weimer's user avatar
3 votes

How do you get a closed vessel to >90,000 psi internal pressure

Contact an engineering firm with experience designing and building such systems and vessels to code. Otherwise, you're just building a bomb.
DLS3141's user avatar
  • 2,145
3 votes

Boiling Point, Pressure and Distillation

In ambient pressure, ethane boiling point is -89 °C; ethylene boiling point is -103.7 °C. Water, to act as efficient coolant needs to be liquid, so above 0 °C. You're not going to condense ethane ...
SF.'s user avatar
  • 6,105
3 votes

Valve first,then heat exchanger OR heat exchanger first then valve

I think the key information is that the liquid is saturated. This means any reduction in pressure will lead to partial vaporization and two phase flow. For heat tranfer best overall heat transfer ...
Ohio ChemE's user avatar
3 votes

What is the fouling effect (in rate, foulant thickness) of sand inside tube side of a shell and tube heat exchanger?

There is quite a bit to unpack here, so I may need to deconstruct your question a bit. Your question is surrounding the fouling rate of a Shell & Tube (S&T) heat exchanger which I will get to, ...
ChemE mang's user avatar
3 votes

How to automate this seemingly easy manufacturing process?

In the past this would have been done entirely mechanically (apart from the electric weld). Station Description Strip unwind Feed in a roll of strip on the left. Strip flatten Run it through some ...
Transistor's user avatar
  • 10.9k
3 votes

Where do engineers find the manufacturing processes of objects?

I can't read your instructor's mind, so I can't be sure this is what they intend, but: the fact you've been asked to disassemble the object suggests to me that you're expected to look for physical ...
Daniel Hatton's user avatar
3 votes

Where do engineers find the manufacturing processes of objects?

Take the object fully apart. Inspect each component and consider it. Is it standardized like a screw or gear? If that's the case internet search to see how those are made. Done. Even for parts that ...
Drew's user avatar
  • 1,981
2 votes
Accepted

Derivation of Overall Mass Transfer Coefficient

Regarding $k_p$: So, you've got $N_1$ a flux in $mol/ s \cdot m^2 $ and a partial pressures $p_i$ in $Pa$. $k_p$ has got to connect those, and make the units work out. Exactly what $k_p$ is depends ...
Dan's user avatar
  • 1,976
2 votes

How do you calculate the required power of a disk turbine (Rushton turbine) to rotate a fluid at a given speed?

We have a fair share of questions about how to calculate maximum speed, but the fact remains that this is extremely hard calculation to make. See a mass will continue to accelerate until the losses ...
joojaa's user avatar
  • 3,577
2 votes
Accepted

How exactly do noise canceling headphones work?

Briefly they take the waveform of the ambient noise then produce the inverse waveform which is then generated. The two waveforms effectively cancel out leaving a much quieter ambient sound level. The ...
Solar Mike's user avatar
  • 15.9k
2 votes

Modelling reactor jacket with or without insulation, how to proceed?

Full Analysis Perfectly Insulated System The best case is to analyze this system in both the time and position domains. The time domain considers the variation of the reactor temperature $T_r(t)$ ...
Jeffrey J Weimer's user avatar
2 votes

Entrainers to distill MTBE from Methanol? - Chemical Engineering Question

Few points: First off, see if you can figure out a way to NOT use MTBE in the first place since it is not an environmentally friendly chemical. That being said, in dealing with separating azeotropic ...
Monty's user avatar
  • 131
2 votes

Recommended models for mineral liberation in crushers

You might want to look up the the "Bond Work Index". It's an empirical method for understanding the energy required to achieve certain amounts of comminution (think P80) for a given method and mineral....
FooAnon's user avatar
  • 131
2 votes

How to add a controlled amount of a nutrient solution to a water line

Our water purification system uses an injection pump, in this case a diaphragm style pump. It has a control for volume dispensed during operation. The operation is limited to when water is flowing by ...
fred_dot_u's user avatar
  • 7,227
2 votes

Identification a Symbol for P&ID's Standards

I would guess it's a non-standard symbol for a check valve. @NMech is correct that it looks like a diode, but that would not appear on a P&ID. A check valve is a fluid flow equivalent of a diode ...
Mark's user avatar
  • 1,012
2 votes
Accepted

What type of electrical machine component for counting time?

Omron makes a wide variety of industrial timer modules which can count down a preset number of tenths of a second all the way to hundreds of hours and then close or open a set of switch contacts and ...
niels nielsen's user avatar
2 votes
Accepted

What is exactly dead-burnt lime, and why is less reactive than quicklime?

After calcium carbonate (lime rock) is heated in a kiln to form calcium oxide, it must be slaked (mixed with water) to form calcium hydroxide. This may occur right away in a sugar processing plant, or ...
ericnutsch's user avatar
  • 8,181
1 vote

Solving a linear mass balance equation in the form of Ax = 0 with variables in vector x

You don't need a computer program to solve this. You can almost do it in your head. The last equation is satisfied by any values of $x, y, z$ so you can forget about it. If you multiply out the ...
alephzero's user avatar
  • 12.5k
1 vote

Designing a Chilled Process Water System for Small Plant

Disclaimer 1: I've dealt with heating circuits, never with cooling circuits Disclaimer 2: I don't feel like doing your math for you, I'll just show the way. Here's how I would set it up (ignore the ...
mart's user avatar
  • 4,791
1 vote

If I replace a flow orifice with a Coriolis flow meter of the same size do I need to worry about pressure drop with the new Coriolis meter?

Usually flow orifices are very aggresive to the pressure. Everything you add has a pressure drop and doing calculations by hand of an equipment like that can be hell. So yes you should check the specs ...
Media's user avatar
  • 109
1 vote
Accepted

Can Fortran 90 be used with Aspen Plus, or only Fortran 77?

Nat was right that Aspen doesn't care as long as your compiler can produce a DLL from the Fortran 90 code (which most do). However, I found that the Aspen files that need to be included in most user ...
Zach's user avatar
  • 21

Only top scored, non community-wiki answers of a minimum length are eligible