Animated Double Acting Compressor Cylinder

Double Acting Cylinder animation showing suction and discharge valve gas flow linked to location on pressure cards

[@ACIServicesInc]

The piston does move the gas, but more so, it actually compresses the gas. The piston pulls back and generates a lower pressure inside the cylinder bore which in turn allows the suction valves to open. The gas that fills from the suction valves is then compressed to a higher pressure which at a certain point of the higher pressure, the discharge valves will open and pushes it now out of the cylinder. The stroke of the piston discharge is equal amounts of gas out of the cylinder.

[@rrpainter]

Super Fun Time had a question about the head end unloader pictured on the left of the animation. Super fun time is correct the actuator that opens this volume which adds additional clearance is not a timed event associated with the operation of the cylinder. It is controlled externally usually be the control panel or a manual solenoid switch. This clearance is added based on the operating map of the compressor which is determined by pressure and temperature as well as the limitations of the reciprocating compressor - rod load, non-pin reversal, etc. One analogy might help - Many times the clearance is added because the additional clearance makes the force needed to compress on that end of the cylinder less. So many times the clearance is added when starting a unit so the driver does not stall. It's like driving a semi up a hill if you start in a high gear the truck will stall. So many compressors will have many load steps and will decrease clearance in steps to use more torque and flow more gas. Again, usually done with a control panel that optimizes the compressor.

[@Danfranschwan2]

Ooooh ! makes sense now ^^ I´ve been watching animations of engines etc. and din't think of taht back then :D atleast it makes sense now :D thx

[@latestbuzz5066]

😊

[@jhlagann8975]

pretty understandable

[@YangSword9x]

Is this air compressor more efficient than a car turbo- air compressor? Are turbo air-compressors not able to make high psi air because of air surge through the blades? Or can turbo make the same psi just as easily as a air pump? Are air pumps more efficient at making pressurized and cooling down air because it has a chamber to contain and pressurize air, which turbo does not have?

[@sathishgujjunuri7677]

Spr ,clear animation..tq. Keep rocking

[@SupriYanto-dd6gp]

Very good thanks.

[@jaspalbatham]

very nice and helpful video too understand such complicated machine. can u please add two stage after cooler inter cooler reciprocating air compressor animated video ???

[@Rinnu224]

valuable video to understand the basic concept

[@carloscristanchoclavijo689]

Nice, nice, very nice! Thanks!

[@ACIServicesInc]

Thank you!

[@vinodujval2145]

very nice

[@ACIServicesInc]

We appreciate your inquiry and will be contacting you soon with an answer.

[@abiadickson6078]

Thank you

[@chadgra]

wish there was a animation that would explain or show a labrinth seal failure and how to trouble shoot.

[@anilkumaryadav2885]

very good video

[@misterloukasgmailcom]

how can I set screw?

[@ACIServicesInc]

Thank you for the comment. This is a compressor and please note the change in the video title.

[@latestbuzz5066]

Okay

[@Srk7028]

hii nice video. Which software u using to do such animations ?

[@ACIServicesInc]

Dear Akash, Thank you for your inquiry. ACI has not posted any of those types of videos. You may want to search within KZbin other than our channel.

[@kevaniko86]

does it not need lubrication? this compressor seems smart and compact but how you can lubricate it when the piston's both side is used for compression?

[@dwayneoh]

Depends. Most cylinders are lubricated via a force lubrication system. In the case of cylinders, a small hole, typically in about the middle of the cylinder, feeds small amounts of oil into the cylinder. That oil lubricates the cylinder, the piston, etc. and reduces frictional forces, and helps to seal gas between the head end (outboard) and the crank end (inboard) sections. However, oil is not always desirable, and some cylinders are non-lube. For these, typically Teflon-type seals and rings are used to reduce friction.

[@ACIServicesInc]

There is currently no audio for this animation.

[@Mangyek0]

Are there videos of single acting compressors, single stage and double stage compressors ? Its all just confusing..

[@Bharatsingh-bx7nv]

i think this is good but i have one question connected rod will be soo much affect just because of continuous cooling and hot temp. else it will get damage easily.acording to mee. soo please explain this.

[@dwayneoh]

For a reciprocating compressor the term "connecting rod" (not shown in this video) connects the crosshead to the crankshaft. Thus, I believe the note is about the piston rod (connects the piston to the crosshead). For this piston rod, metal does not heat and cool all that quick, and these compression events vary from 5 times per second (on 300 rpm units) to 30 times per second (on 1800 rpm units). Thus, the temperatures of the piston, the rod, the cylinder body, etc. do not quickly change. That said, some gases being compressed are cryogenic and those may be coming in at -200 degF to -40 degF (-130 degC to -40 degC). These extreme temperatures can be more challenging (due to embrittlement issues of metal) during unit start up, but again, once running, quick temperature swings on components is not seen.

[@thisisshiva44]

Can i get the audio ?

[@saxriyarmamedov]

hi thanks for video.can you make a video about compressor of 10 qmk

[@BeWithWasif101]

nice

[@prasadneerukonda]

Nice

[@markranielochigue4660]

Referring to the left side of the animation, is that an "extra suction"? If so, is it's function/operation periodical?

[@cavemansmancave9025]

Mark, no it's additional compression volume also known as added fixed clearance. A compressor is designed with a certain amount of fixed clearance to achieve optimum performance at design conditions. If conditions change in such a way that the compressor is no longer operating under design conditions ( which happens a lot), the compressor may require more power than the driver can supply. To reduce the power required to operate, additional clearance is needed to reduce the amount of compression taking place which reduces the amount of power required. The device shown on the left end of the cylinder is an valve and volume device called a fixed clearance pocket. When the valve is closed, the compressor is operating at full load. When the valve is opened, the device adds more fixed clearance to the compression volume. By adding this clearance to the compression volume, less compression takes place which means less work is done which means less power is needed. Devices like this are often referred to as unloaders. I hope this helps. Thanks, John

[@dwayneoh]

On the left side is a "fixed volume clearance pocket". The pocket is opened as needed to reduce flow (or load) (and hence closed to increase load or flow as needed). Adding more volume (clearance) to the cylinder's end delays the compression event by forcing the internal pressure to rise more slowly during the compression event (and falls more slows during the expansion event). As such, less gas is effectively compressed, and hence reducing flow (and for clearance pockets, also reducing load). These types of devices are often added to reciprocating compressors to allow them to dynamically load and unload to meet compression goals across wide ranges of operating pressures.

[@ACIServicesInc]

Please note the title change and thank you for your comment.

[@ACIServicesInc]

Bharathi - what exactly is it that you are expecting from this animation?

[@mohammadazas1658]

Can u explain multi stage compressors with intercooler

[@dwayneoh]

For a reciprocating compressor, there can be multiple limitations for compressing the gas in one stroke, but the two most common issues are 1) high stresses on the rod and/or pin, and 2) high temperatures (as the pressure goes up, so does the temperature). Both issues can be addressed nicely by splitting the compressing event into multiple stages. Thus, the first stage might take gas from X pressure to 3*X, and then the next stage takes it from roughly that 3*X to 9*X. That solution typically helps the mechanical stresses within a particular cylinder. However, it does not address the high temperature issue. So, to handle the high temperatures, a cooler is added between the stages. This reduces the temperature of the gas after that first stage back down, and then that cooler gas can then go into the next stage. For example, to compress from 10 AbsPressure gas to 120 AbsPressure gas, you need about (120 / 10) or 12 ratios of compression. That's generally too much for stresses and temperatures. Thus, look at SQRT(12) = 3.46, or we need roughly 3.5 ratios per stage. Hence, the first stage compresses gas from 10 AbsPressure (and say 15 degC) to 35 AbsPressure (and say 127 degC), we cool that gas down to say 49 degC and the second stage takes it from 35 AbsPressure (and 49 degC) to 120 AbsPressure (and say 160 degC). Thus, we can compress from 10 to 120 without breaking anything, or having temperatures so hot that they melt critical components (such as valves, rings, seal, etc.)

[@superfuntime3107]

What is the function of the valve and the chamber on the far left ?

[@rrpainter]

If I understand the question correctly. You are talking about the little red area on the far left. This is an air cylinder. It is used to actuate the shaft up and down or back and forth in this case in order to remove the plug from the seat and add clearance to the cylinder.

[@superfuntime3107]

@@rrpainter But it is not timed in any sequence with main shaft. I don't understand please explain differently. The animation looks incomplete.

[@nevermind6726]

Why there is a high temperature at 50% compressor load.

[@dwayneoh]

Discharge temperature (Td) is related to Inlet Temperature (Ts), Compression Ratio (CR), and the exponential rise value of the gas (aka GasK value), typically by Td = Ts * CR ^ (1-1/GasK), where temperatures are in degR or K. Thus, the Td can easily exceed a limit while the overall load on the compressor is low, moderate, or high.

[@nivasnanchari8272]

good But if there was an explanation abt it it would awesome

[@Prishni829]

Thank you for the very informative video... What does the valve present on the left, the one shown in green color do.. or what is its significance. Please explain... Best Regards,

[@ACIServicesInc]

Asutosh, The green device located on the cylinder’s left end is a pneumatic actuator that opens (and closes) to allow (and prevent) the gas being compressed into the added volume section (known as a fixed volume clearance pocket). When open, more clearance volume is added to the cylinder’s head end and thus the compressor’s overall load (HP, KW) and its overall flow rate (MMscfd, scfm, Kg/hr, etc.) are reduced. When closed, less clearance volume is available and thus the load and flow rate are increased.

[@MrVictornana48]

ACI Services, Inc. thanks for your animation. could you please eloberate more on clearance pocket?? what will be the position of the clearance pocket when the compressor load at 50%?? on which factor loading of the compressor depends.like i found some compressors having 110% also..i little bit confused. thanks

[@ACIServicesInc]

Dear Sir, Thank you for your interest in our video. I would like to guide you to our website for more information, www.ACIServicesInc.com. In particular: 1) To elaborate more on clearance pocket, please navigate to www.aciservicesinc.com/performance-control-devices/. A clearance pocket is a means to control the effective clearance in a cylinder end. Thus providing the ability to control the volumetric efficiency and hence capacity. 2) In order to control the compressor load, one has to evaluate the performance of the compressor accordingly to identify the volume of the clearance pocket to effectively control the load to 50% as there are many variables to consider, such as operating pressures, gas analysis, speed, stroke, and cylinder bore diameter. 3) I am not sure what you are referring to when you mention 110%. It is possible for compressors to require more power than what is available from the driver as operating pressures may change. Variable such as suction and discharge pressure and temperatures play a key role in the power consumption required. If you are interested, ACI can help evaluate the performance of a compressor to identify a possible performance control selection to ensure operation closer to 100% and 50% if that is the requirement. Please feel free to reach out via email if you have any questions.

[@studysrr7822]

Super

[@ACIServicesInc]

Glad you like!

[@ACIServicesInc]

At this time, there is no audio.

[@dharmsinghrajput9704]

this engine work 2times of single acting engine in one cycle the crank subjected to this cyllinder rotate two cycle

[@khalidfahad356]

We have one comp alwys raider ring damge and liner scratch

[@ACIServicesInc]

Thank you for the comment. We would be most interested in discussing further, if you are able to share additional details such as equipment model, operating conditions, operating speed gas analysis, ACI would be able to assist. Please feel free to email us at [e-mail]

[@harinderprasad851]

ACI Services, Inc. and the

[@Danfranschwan2]

This animation makes little to no sense to me ?! looks like a double 2 stroke engine but with missing/wrong ignition of the gas ? when the blue gas turns red -(which means ignition to me ), comes compression instead expansion .. so the shown movement of the cylinder can't happen like shown in the animation ... did I miss something ?!

[@Detective774]

How can find efficiency

[@dwayneoh]

Finding the "efficiency" of a compressor is subject to starting and stopping points considered during the compression. For some (e.g. end users), this is "fence to fence" (e.g. inlet into the station to outlet out of the station), whereas others (e.g. compressor manufacturers) tend to prefer "flange to flange" (e.g. gas into the compressor cylinder to out of the compressor cylinder). Both have merits for their use. The former as it covers all losses associated with the application, including pressure drops through piping, restrictive orifice plates, pulsation bottles choke tubes, coolers, scrubbers, etc. In short, if something is needed to make sure that the compressor runs and runs safely, then that needs to be included in the overall unit efficiency. The latter as is covers the losses associated with the actual compressor itself. Namely, frame friction, mechanical losses/cylinder friction, valve losses (pulling and pushing gas through valves), parasitic losses from certain unloading devices, etc. In short, things that the compressor manufacturer has control and accountability over. In short, Efficiency (often referred to as Isentropic Efficiency) is the measure of how much power is takes to actually compress the gas relative to how much power it takes to actually complete the compression event. For example, it might take 100 HP (75 KW) to compress a volume of Natural Gas from Pressure A to Pressure B in an ideal compression event (no losses). But if your compressor takes 120 HP to do this, then its Isentropic Efficiency is 100/120 = 83.3%. Now finding the amount of work to compress gas without losses starts to involve Enthalpy and Entropy changes, and thus you're getting into Gas Thermodynamics. However, most compressor efficiencies will be based on more specific details of the equipment and system. For a reciprocating compressor, the general guideline is Eff = IIHP / [ (IIHP + VL + PL)/ME + FF + AuxHP ] , where: IIHP = Ideal Indicated Horsepower: Sum of (HP per Cylinder End), for all cylinders ends compressing gas ME = Mechanical Efficiency: To account for cylinder friction, typically 95% for Recips (there's field data to prove this is a good value). VL = Valve Losses: Sum of (Suction and Discharge Valve Losses), for all cylinders ends compressing gas PL = Parasitic Losses: Sum of (Deactivated End Losses), for all cylinders ends NOT compressing gas FF = Frame Friction, generally about 1-2% of frame's Rated Load, varies with speed. AuxHP = Auxiliary Load, power required for additional fans, coolers, pumps, etc. required during operations. Most slow-speed reciprocating compressors will tend to be in the 85%-95% Efficiency range. Most high-speed reciprocating compressors will tend to be in the 75%-90% Efficiency range. Example: If IIHP was 1000 HP, Valve losses are generally 5-10% (can be from 1%-50%) and we'll use 8% here, Parasitic Losses are often zero, Frame Friction is general 1%, ME is 95%, and AuxHP is often 0 HP. Thus: Eff = 1000 / [ (1000 + 80 + 0)/0.95 + 10 + 0) = 87.2%. Now, another "Efficiency" often used is BHPMM which is an abbreviation for BHP per Million Flow. Thus, the real concept (ratio) is Power/Flow. In short, we want to pay (power costs us) as least as we can while obtaining as much flow (flow makes us money) as possible. That is, this ratio helps users better understand how much each Million of flow is "costing". Be aware that at times Isentropic Efficiency may get better, but BHPMM gets worse, they both go together, or BHPMM gets better while Isentropic Efficiency gets worse. If someone is only concentrating on one o those efficiency measures, they may well be trying to avoid/hide important conversations/information.

[@andres1980b]

It's a compressor, not an engine. It should be in title and/or description.

[@ACIServicesInc]

This animation was done by a third-party for us and the software they used is unknown to us.

[@bharathiraja7733]

animation is good but i m expecting stil more

[@eslpaKo]

there is no sound! the explanation is needed to know how it works, not everyone knows about the physics!

[@pramodkinge8225]

But action is sufficient to know working..!!

[@ACIServicesInc]

The piston does move the gas, but more so, it actually compresses the gas. The piston pulls back and generates a lower pressure inside the cylinder bore which in turn allows the suction valves to open. The gas that fills from the suction valves is then compressed to a higher pressure which at a certain point of the higher pressure, the discharge valves will open and pushes it now out of the cylinder. The stroke of the piston discharge is equal amounts of gas out of the cylinder.