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18

This is not a factor in practice: Water (and entrained solids) directed into a vertical pipe segment adhere to the sides of the pipe. I.e., there is no free-fall in a vertical waste pipe. Rather, liquids swirl around the side of the pipe (producing a self-cleaning effect known as scouring). Even if you managed to introduce a dense solid with insufficient ...


9

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 holes are expressed in inch units only. These systems of units are to be regarded separately as standard. Within the text, the U.S. Customary units are ...


9

I have done this before so would like to share some of what I know. Super critical CO2 has some unique properties, for one it is extremely difficult to keep in a closed container since it has near zero surface tension. As such, if a standard threaded fitting is used and the fluid comes into contact with it you can be fairly certain it will leak (and usually ...


7

You are correct in your assumption that corrugations give pipes strength and hence such pipes can have thinner walls that smooth walled pipes made of the same material when used for the same application. Pipelines are made to transport fluids or slurries. When it comes to the flow of fluids or slurries in a pipe, one of the import considerations is the ...


6

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


6

Think about the pressures. With the pump above the supply line, the pressure at the input of the pump will be lower than the supply. At roughly 2 PSI per foot, you're down about 18 PSI. Since air pressure is about 15 PSI, the system will at least work as long as the supply pressure is over 3 PSI, but that's still not a good situation. If the "supply" is ...


5

You can get a minimum bound from energy balance alone. This is as if the fluid has no viscosity, so the force you have to apply over the distance is only due to the kinetic energy required to expell the fluid. The diameter of the tube is 1 cm, so the area is .785 cm². That means the plunger travel distance is 25.5 cm = 0.255 m. The fluid is squeezed ...


5

Although it doesn't corrode in the same say that steel does, plastic also degrades over time. The common corrugated steel pipes are galvanized, so take some time to corrode. Concrete is usually used to support larger soil pressure from the outside. Corrugated steel pipe can sometimes get squished by the pressure of the soil, especially when it's a bit ...


4

The way of removing couplings in the worst case scenario, where all other alternatives has failed, is to physically destroy the coupling. Cut/grind 2 slots the entire length of the coupling on opposite sides, usually one on top and one on the bottom. The slots need to be deep enough that it is at least flush with the pipe its screwed onto, pretty much as ...


4

It is called a "steam wand gasket". Technically, it's a ball-and-socket joint made out of two concave PTFE (Teflon) gaskets and an EDPM gasket for the seal. There may be other designs too; I learned this by watching Saeco StarBucks Barista - How to Replace Steam Wand Seals and Gasket (YouTube video).


4

A Mechanical engineer, or some one who works in materials/reliability would be better suited to answer this, but I believe the reasoning to be the a combination of safety factor (ensuring fittings, gaskets, etc are all going to withstand the pressure load) in addition to the difference between peak acute strength vs sustained or cyclic loads. MAWP stands for ...


3

Cold bending steel, especially with a relatively thin wall, is difficult to do accurately. Typically the standard for custom parts like this is that the shape is close enough that the person installing it can bend the pipe into the final curve with the use of clamps. Then they weld it in place so it keeps its shape. I'm going to assume that you're already ...


3

Notice that the "shapes" are in a right angled bend where the flow changes directions. Sometimes vanes are placed in right angled bends to reduce shock losses by reducing the turbulence of the flow as it goes through the bend. The "shapes" the picture appear to be on the outside of the bend, in which case they have been placed there to reinforce the bend ...


3

The manufacturer says this about maintanence: annual testing of the non-return valve, body leak tightness and flow capacity is recommended WITT is happy to supply special test equipment Flashback Arrestors are only to be serviced by the manufacturer; the dirt filter may be replaced by competent staff Given that you inherit this equipment ...


3

Typically, most threads on pipes (in the USA at least) are male NPT and all the couplings or fittings are female NPT. You can connect two pipes with a coupling as long as the last pipe added is free to rotate about its axis. A union is used for easy removal of pumps and other serviceable equipment that would otherwise not be easily unthreaded. It is also ...


3

Firstly, I assume that when you say "tube" what you mean is Hollow Structural Sections, and when you say "pipe" I assume that you mean typical scheduled pipe sections. In the US, the AISC Code specifies material properties for structural shapes. From the manual Tables 2-4, we can see that the Pipe material is ASTM A53 Gr. B, and that for round HSS we have ...


3

The advertisement referenced in the question was written by a liberal arts major without much of a clue what he was writing about. Pipe comes in certain diameters and wall thicknesses and threads defined by ANSI OR API ( in the US, code bodies in other countries usually follow these same sizes - such as CSA in Canada). Pipe and tube may be made of the same ...


3

Here is a reference from RoyMech, see section under "Orifice Flow Meter". The setup has the orifice placed in a pipe. Below is a similar, perhaps simpler, expression, from Jobson 1955, part of the way between equations (4) and (5) of that paper. (The paper is really about incompressible flow, this is just a warmup for the author). $$\dot{m} = {{\...


2

I'm sure there are specific strategies relating to pipe flanges, but for the broader issue of controlling that all of your bolts are tight enough, here is some background information. When tightening bolts in any clamping application, what's really important is the total clamping force. In any simple joint, and specifically when dealing with pipe flanges, ...


2

Although i know is's not the right answer, i would like to mention that using a micrometer to measure bolt length out of nut can be helpful, because that is proportional to torque, so for same installations one can use it to check if all bolts have the same load. another option when a torque meter is not helpful is to use smart bolts. they have internal ...


2

Based on your translation of 'root face' I'm assuming that the bevel they are inspecting is a bevel that has been prepared for a groove weld between two pipes. If that's the case, the typical measurement tool, at least in America, would be a weld inspector's gauge like this one. There are various designs of gauge that do the job, but a Bridge Cam gauge is ...


2

Considering this is a centrifugal water pump, it can provide very little air suction. That means if your pump is airlocked, there's not a shade of a chance it will be able to produce nearly enough suction to pull the water up two floors. And it will be airlocked all the time. With a check valve preventing backflow into the mains, and then filling the water ...


2

Pipe comes in different wall thicknesses, designated schedule 40, Sch. 80, Sch. 10, etc. Higher numbers are thicker walls. The outer diameter is the same for all schedules, so the inner diameter varies. The nominal size is close to - but not exactly - the actual inner diameter for schedule 40 pipe. Here is a chart summarizing the dimensions


2

The problem with older and under-maintained (this is South Africa after all) systems is that the pipes get brittle, rusted and joints fragile and the network won't be able to handle the transient forces of constantly opening and closing valves, even if it's done slowly. The networks are in general not designed to withstand such large constant cyclic loading ...


2

It is difficult to provide a useful answer to this question without additional information. For example, what is the system pressurization - operating psi/bars? Having installed ductile iron water mains, and having pressure tested new installations to destruction (resulting from hairline cracks in new pipes), I can confirm that the effects can potentially ...


2

The flange on the pipes are beveled and the groove in the clamp is V shaped. There is also a seal between the 2 pipes. As the clamp is screwed down it will force the 2 ends together. The dimensions are such that the clamp will not bottom out without providing enough pressure to ensure water tightness.


2

Simply if you remove the ventilation then you create a closed tube where the « piston » ie waste is trying to create a vacuum behind it, that is, untill it can draw past the liquid in the u-bend...


2

Two of those are not standard usage symbols in that way. You may to have to use context and/or a physical inspection to determine what they are. Where is that diagram from? Various organizations define symbols for piping and/or control. The International Society of Automation uses ANSI/ISA-5.1-2009, which you can officially find on their website. The top ...


2

The "area" terms in the equations all cancel out. Think about a section of pipe of internal diameter $d$, length $l$, thickness $t$ with internal pressure $P$. Now imagine you slice the section of pipe (and the fluid causing the internal pressure) into two semicircular parts, and think about the forces acting one of the parts. The "area" of the cut through ...


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