# Tag Info

### General term for a technique that ensures that two parts can be mated only if they are meant to be mated, and prevent any other part from mating

The general term for a technique that ensures that two parts can be mated only if they are meant to be mated and prevents any other parts from mating is called Key Interlocking or Keying.
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### What would be an ideal material to use for O-rings on a canister in a lubricant-less, high-velocity pneumatic tube system?

A commonly used material for O-rings in high-pressure applications is Fluorocarbon (Viton) which has good resistance to chemicals, high temperatures, and good sealing properties. Other materials to ...
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### How to find press fit/ slip fit for non standard size parts?

The calculations for slip fit and press fit can be done using the following formulas: Slip fit: Hole size = Dowel Pin diameter + clearance (C) Clearance (C) = (Upper tolerance of the dowel pin - Lower ...
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### Input power unit for Heavy Duty spool hose

A hydraulic motor would be a suitable solution for your application, given its high torque capability and ability to operate in harsh environments. To find a hydraulic motor that would suit your ...
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1 vote

### 2-speed 2-direction gearbox design

A simple solution for a gearbox with the desired properties is to use a planetary gearset. Planetary gearsets can provide different gear ratios based on the rotation direction of the input shaft. They ...
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### How to design a gear decoupling system?

You can consider using a simple mechanical locking mechanism such as a deadbolt or latch bolt that can be unlocked using a key, as well as a motor or servo to actuate the mechanism. This allows you to ...
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### On a Diesel/hydraulic DMU train what exactly does the “go faster” lever control?

When you move the "go faster" lever in a Diesel Multiple Unit with a mechanical or hydraulic transmission, you are commanding the transmission to shift to a higher gear ratio. This allows ...
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### Forcing a part into "home position"

One approach could be to use a spring mechanism to keep the block in the home position. For example, a spring could be mounted on the inside of the ring near the bottom and connect to the bottom of ...
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### Backward stabilization of a Z-axis

It's better to place the stabilizing pieces behind the rails, as this would provide more stability to the system and help to keep the plate and the rail level. The placement on the edge of the plate ...
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### Stress and Displacement of Cantilever Plate with a Uniform Load

For bending of wide plates, we typically use the so-called plane-strain modulus $\frac{E}{1-\nu^2}$, where $E$ is Young's modulus and $\nu$ is Poisson's ratio. For $\nu=0.3$, for example—typical for ...
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### Is this proposed addition possible for an evaporative cooler?

The diagram is the proper design diagram for a evaporative cooler, BUT you need to understand a few things: The 25 degree air will be close to 100% relative humidity. Most people will not find this ...
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### Stress and Displacement of Cantilever Plate with a Uniform Load

If you are after the deflection of the beam at any point along the beam (but also for most intends and purposes - see below for exceptions) the problem you are after is equivalent to the following 2D ...
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### Is this proposed addition possible for an evaporative cooler?

Not only is it possible, it is the fundamental invention of effective "air conditioning" Historically, an "air conditioner" was an invention that controlled the humidity of air. ...
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1 vote

### What would be an ideal material to use for O-rings on a canister in a lubricant-less, high-velocity pneumatic tube system?

Precise machining of metals can result in a cylinder/piston fit so tight that it cannot be inserted if the exit hole is blocked. This would be impractical, in my opinion, in your application, as ...
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1 vote
Accepted

### Are there compressors that can compress both water and water vapor?

Water at "normal" pressures is assumed to be incompressible. However, if you subject water to about 200 atmospheres of pressure then its volume will reduce by about 1%. So, water vapor will ...
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### How to stamp a thin copper pipe?

Metal can be very ductile but it is difficult for humans to imagine since we don't normally work with forces that large. Look at how an aluminum soda can is made. It's like forming putty. To me those ...
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1 vote

### Centrifugal Pumps Self Priming

Because sometimes your pump is placed above and some distance from the waterline. but lets look at the startup sequence when the inlet is full drained and the housing is still full of water: When you ...
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### Flopping toy mechanism design

Usually the motor will be heating up when it reaches a "hard limit". At that point it still tries to move (but it can't) and draws too much current while it tries to move. I would start by ...
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### Steel selection for building a trailer

I’m not a structural engineer but I do understand materials and statics. My degree includes engineering, physics, other sciences and math. Long story short I worked as a civil engineer. The first ...
1 vote

### Origins of the "threaded fastener pullout formula"

You are right about the shear cylinder. With a SF of three, the thread's pitch or angle are irrelevant at the point of greatest strength. They assume that ultimately the threads will yield a stripped ...
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### Origins of the "threaded fastener pullout formula"

(adding to DKNguyen answer, and giving a slightly different perspective --hopefully). general calculation The calculation is indeed based on a cylinder surface/plane that transfer the force from one ...
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### Origins of the "threaded fastener pullout formula"

I think you're correct about the cylinder thing. It appears to be a crude equation though since it does not include thread percentage or thread pitch and does not even appear to be assuming a ...
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### How to theoretically determine the flow rate for a fan design?

Flow rate = V_induced * Area of the duct (at the rotor plane) V_induced can be calculated using Momentum (or combined Blade Element Momentum Theory, BEMT), for open rotors. (this reference uses V0 ...
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### Passive gas mixing valve that takes fixed ratio of gas from two different inputs

Such a thing exists for hydraulic system. It is not simple or cheap, but passive. You need two positive displacement machines for the airflows, like sliding vane or rotary lobe pumps. At least the ...
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1 vote

### Can air compressors be used to boil water?

what you propose is capturing the waste heat given off by the cooling fins on the outside of an air compressor's cylinders while the compressor is running. This is certainly feasible, but note the ...
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### Can air compressors be used to boil water?

Yes, submerge the hot parts in water. If you can reach over 100 C, the water will eventually start to boil. You could keep the water at a constant level using a fill valve, such as the type you find ...
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1 vote

### Can air compressors be used to boil water?

This is probably technically feasible (albeit requires a high level of sophistication and there are a lot of asterisks attached to it) but as mentioned above not practical or economical. Air has a ...
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1 vote

### Bending stress in gears

Because energy/power is the invariant which is transmitted through the gearbox (i.e. the power remains the same, while rpm , torque and forces change) , it might help if you think about it in terms ...
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1 vote

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Accepted

### Tension forces in a cable and reaction at the supports

Assuming that the posts are rigid (non deformable) and the rope is weightless, then pole L1 should experience only horizontal forces at the top (which will be converted to shear forces for the pole). ...
• 23.7k
1 vote
Accepted

### What will the reaction forces of a support be in case of an angled cable

The reaction force is a vector in the direction (or opposite) of the cable. Note that the only way to have a horizontal cable is by having the other support higher. But if you do, a horizontal vector ...
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