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how does a hydraulic displacement cylinder work

Cylinder Flow Rate (gpm) = 12 x 60 x cylinder speed (ft/sec) x area (in) / 231 Cylinder Volume Capacity (gals) = cylinder area (in) x cylinder stroke (ins) / 231 Basic Hydraulic Motor Calculations: Motor Torque (in lbs) = pressure (psi) x motor displacement (cu ins/rev) / 6.28 (Can also use horsepower (hp) x 63,025 / speed (rpm) Because of the facts explained above, we can conclude that the power density in the hydraulic cylinder is big; a great force can be created even with a small cylinder. If you want to learn more about hydraulics,contact ustoday! When one cylinder retracts, it transfers force to the next cylinder. How does a hydraulic displacement cylinder work? Some of our calculators and applications let you save application data to your local computer. The winch drum turns at five rpm. . Its just dirt simple design. The larger the rod, the more work can be done. It states that when pressure is applied to a confined fluid area, it will be evenly distributed throughout the entire area. The rod diameter area is the acting force. "url": "https://hcsplating.com/wp-content/uploads/2017/08/hcs-logo.png" However, you may visit "Cookie Settings" to provide a controlled consent. q = volume displacement (gal) A = cylinder area (in 2) s = cylinder stroke (in) 1 in (inch) = 25.4 mm = 2.54 cm = 0.0254 m = 0.08333 ft; 1 in 2 = 6.452 cm 2 = 6 . Non-positive pumps are more common in pneumatics and low-pressure applications. By clicking Accept All, you consent to the use of ALL the cookies. Typically, when the flow divider and crossports are part of the original design, their recommended setting will be provided. To correctly calculate thepulling forceof a cylinder, the surface area of the rod must be subtracted from the formula. The operator summons the winch by moving the spool in the directional valve 20% of its stroke. When oil enters the cylinder the rod is displaced and when the oil is released from the cylinder the force of the load returns the rod into the cylinder. The fluid is carried by the gears to the discharge side of the pump, where the meshing of the gears displaces the fluid.Due to this continual flow of fluid, it is important to know this cc measurement to avoid any system failures and costly repair work.Flowfit have a vast range of hydraulic gear pumps and accessories to choose from. A hydraulic cylinder provides linear force in one axis in either one or two directions (known as a single or double acting cylinder respectively). This then turns the wheels. We have a team of experienced engineers to work with you. In plunger pumps the plunger moves through a stationary packed seal and is pushed into the fluid, while in piston pumps the packed seal is carried on the piston that pushes the fluid out of the cylinder. "headline": "The Complete Guide to Hydraulics Systems", You may be wondering what hydraulics are. Unlike traction elevators, hydraulic systems don't use overhead hoisting machinery. If the area is 10 times the first area, the force on the second piston is 10 times greater, even the pressure is the same throughout the cylinder. These systems mainly use when high power densities are required or when the demand for loads increases quickly. They may be less efficient, however, and wear more quickly. In the example below, a small force F1 applied to a small piston of area A1 causes an increase in the pressure in the fluid. My Yale lift has this type of cylinder. It does not have seals on the piston, only the rod. Cookies are only used in the browser to improve user experience. These two components determine the force that can be exerted by the cylinder. If you cap the end of it with your finger and try to press down, neither the water nor the plunger will go anywhere. This cookie is set by GDPR Cookie Consent plugin. Designs up to 5000 psi working pressure. Hydraulic devices are much more accurate than other forms of the same device. The diameter of the rod is the effective piston area. Piston is more just a guide element. A Hydraulic cylinder consists of numerous delicate parts and components. Every part or component plays a crucial role in making the hydraulic cylinder to function properly. In simpler terms, pressure is applied to a small piston which then creates pressure within the fluid. 2021 Copyright Practicalmachinist.com. The seals keep the fluid where it needs to be; inside the hydraulic cylinder. They really are simple devices, capable of doing tremendous amounts of work. Total weights of telescopic cylinders can often reach nearly 25,000 pounds. This fluid is incompressible, and the path of the fluid is as flexible as the wire. Pascal principle. They are great for powering huge machines without taking up too much space. Open and closed systems of hydraulics refer to different ways of reducing pressure to the pump. If a flow divider has two motors, each of the same displacement, it is called a 50-50 flow divider, as it delivers half the flow that is input out of each motor. Leave this valve open until hydraulic fluid . If you run any sort of business, you may be able to put hydraulics to work for you. However, this type of flow divider can be configured with as many motors as needed, and the displacement of each motor can be different. .001" minimum chrome plated stages. How Hydraulic Cranes Work. Many seals / o-rings are used in a hydraulic cylinder, they are meant to prevent any hydraulic fluid leaking,some can even resist high heat, depend on theirmaterials. Other example: in certain extension cylinders the fluid flows through one cylinder to another in a way that the cylinder that needs the smallest amount of pressure moves first, asP=F/A. Typical load sensing circuit. This conserves energy on a large scale. Usually by using a CLEVIS, CROSS TUBE, PIN-EYE or TANG. Pneumatic cylinders are far less complex than hydraulics, but theyre incredibly accurate in creating linear motion. Or if it does, theres just a real good chance its OEM reusing existing parts in there parts libary. Since my topic included hydraulic troubleshooting, she thought I might be able to assist. . Clockwise rotation of the adjustment screw will increase the pressure setting and counter- clockwise rotation will decrease the pressure setting. Relief valve B and 2-way valve C provide a path for excess oil to go to a tank when the cylinder retracts. We will tell you more about double-acting and single-acting cylinder in our upcoming blogs. browsing data or IP addresses) and use cookies or other identifiers, which are necessary for its functioning and required to achieve the purposes illustrated in the cookie policy. Hydraulic Cylinders - Volume Displacement. We also use third-party cookies that help us analyze and understand how you use this website. In this article, were going to tell you everything you need to know about hydraulic systems. It is single acting, and there is no vent - but instead, there is some sort of bypass hole in the. In a displacement (single acting) cylinder the rod is extended by flowing pressurized oil behind the rod, which forces the rod out of the barrel like a piston. Clockwise rotation of the adjustment screw will increase the pressure setting and counter- clockwise rotation will decrease the pressure setting. How does a variable displacement hydraulic pump work? A Positive Displacement Pump must never operate against closed valves on the discharge side of the pump - it has no shut-off . In a displacement (single acting) cylinder the rod is extended by flowing pressurized oil behind the rod, which forces the rod out of the barrel like a piston. Hydraulic Pump/Motor Division Hydraulic Pump Basics Types of Hydraulic Pumps Centrifugal Flow dependent on speed and outlet pressure Primarily fluid transfer Positive Displacement Flow dependent on speed and displacement, independent of pressure Primarily fluid power Flow can then continue to the slower actuator and enable it to reach its limit. 3 or cm 3 per revolution. In short, hydraulic cylinders provide large machines with agility that wouldnt be possible otherwise. Arrangements like this can be used in a wide variety of general-purpose maintenance situations, or in a hydraulic press. A plunger pump operates using the reciprocating motion of plungers or pistons. Water flows along the channel at a low Reynolds number, so the inertia forces are not important. "@type": "ImageObject", A pressure used on a piston produces an equal increase in pressure on the second piston in the system. Every part or component plays a crucial role in making the hydraulic cylinder to function properly. To do so follow the formula below: Area = D^2 (diameter) x /4. Sign up to our newsletter to receive industry and company updates. You can even convert an open system into a closed system by replacing some of the components and adding space for the oil to go after the return trip. Once the pressure is released, the load on the cylinder retracts the rod. Hydraulic actuators operate on the basis of Pascals Principle of fluid mechanics. Pump creates a decreasing volume at the pressure side, forcing fluid out via the discharge port. Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. You are using an out of date browser. Such a unit can be mounted anywhere in the engine compartment instead of having to be directly in front of the pedal. They provide motion of a fluid in straight line. "description": "From the elevator you take at work to the dump truck you see rolling by on the street, hydraulics are everywhere. For example, if one motor has a displacement that is three times that of the second motor, it would be called a 75-25 flow divider. It uses a single central pump to move the fluid in a continuous loop. The aircraft hydraulic pump is a variable-displacement, pressure-compensated unit that adjusts the volume of fluid delivered to maintain constant pressure. Now that you have formulated the working area of the system's cylinder you can plug that data into the formula below and calculate the push force of your hydraulic cylinder. In other words, if you apply pressure to one end of a container of water, the same pressure will be applied to the other side. This principle is what allows the force to be multiplied and affect a larger, heavier object. I copied them and sent to my friend; he responded that the cylinder he is working on doesn't quite match the displacement design you all have described, because there. A valve also blocks oil from the pump, instead sending it to an accumulator where it stays pressurized. Enlarge To understand how the load-sensing pump and directional control valve function together in operation, consider a winch being driven through a manually actuated valve. Aside from construction machines, hydraulics are used for everything from elevators to motors, even in airplane controls. The counter movement is created when oil is driven to the other chamber and the piston moves back, pulling the rod. To start from scratch, a hydraulic cylinder forms its force from pressurized fluid. The displacement, or amount of fluid pumped per revolution of the pumps input shaft can be varied while the pump is running. In a displacement (single acting) cylinder the rod is extended by flowing pressurized oil behind the rod, which forces the rod out of the barrel like a piston. Pascals Principle states that, in a confined space, any change in pressure applied to a fluid transmits through the fluid in every direction. To learn more, please refer to the cookie policy. There may also be a relief valve in the circuit to route any excess fluid to the reservoir. How does the hydraulic cylinder work? While speaking at a conference a few years ago, I met a woman from the Department of Transportation. Hydraulic cylinders are linear drivers which use fluid pressure to counter the movement under load. We will talk about others as we move on. Hydraulics can also be very flexible, and there are many different types of hydraulic systems. Both the inlet to the pump and the return valve are hooked up to a hydraulic reservoir. A hydraulic system is a transmission technology that uses fluid to transfer energy from an electric motor to an actuator such as a hydraulic cylinder. TheSTROKEof the cylinder is the total travel possible from the fully retracted length and the fully extended length of the rod. In double acting hydraulic cylinder models, fluid moves into one port and exits through a second port, forcing the cylinder to retract and extend. Hydraulic energy can be referred to as the pressure needed by actuators to function. Any combination may be designed, but the most common are those with motors of equal displacement so the input flow is divided equally between each outlet to the actuators. For example, if you press down on the narrow end with high speed and low force, youll apply high force but low speed to the wide end. Once the crossport relief valves were added, the cylinders synched up and all vibration ceased. Second, its mechanical action delivers this liquid to the pump outlet and forces it into the hydraulic system. This includes large cranes, packing machines, lifts, drills, and dump trucks. Lines are under extraordinary pressure so if they burst, theres a chance of severe injury. A safematic system in a steering gear system allows for automatic isolation of defective or leaking hydraulic part of system changing over to the remaining hydraulic pump, hydraulic cylinder and mechanical system for the steering assembly.It is not an separate steering unit but just an independent control unit to . Home Blog Cylinders What is a Hydraulic Cylinder? Crossports added to the original Jack has Unboxing: Mystik JT-9 LeakShield AW Hydraulic Oil, Why You Shouldnt Overlook Hydraulic Pipe Size, Understanding Logic Valves in Hydraulic Systems, FS9V4 Particle Pal Plus w/ Atten2 Particle Counting & ID Technology, Shell Turbine Oil with Gas To Liquid Technology (Turbo S4 X & GX), Key Grease Tests for Selecting a Heavy-Duty Grease, How to Cost Justify a Lubrication Program. Pneumatic cylinders are also less efficient because the compressor must constantly run even if the cylinder isnt moving. The design is also a safety feature. AddThis use cookies for handling links to social media. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. Pressure and flow are integral to the hydraulics process, and one cannot work without the other. A single-acting hydraulic cylinder . After you have brought all the air to the top of the single acting hydraulic cylinder, you will need to close it but not completely. But opting out of some of these cookies may affect your browsing experience. The apparatus works with a steady, air-free water supply and suitable drain. According to Pascal's principle, the pressure is equal to the force divided by the area on which it acts. Also called push cylinders, they feature a single-acting piston that moves in one direction and requires a motor or spring to reset its position. If you have read How Hydraulic Machines Work, you will know the hydraulic crane is dependant on an easy concept the transmission of forces from indicate point via a fluid. A Positive Displacement Pump, unlike a Centrifugal or Roto-dynamic Pump, will produce the same flow at a given speed (RPM) no matter the discharge pressure. "url": "https://hcsplating.com/" Most pumps fall under fixed displacement. This cylinder can be used in an application where work can be done by both ends of the cylinder, thereby making the cylinder more productive. It is single acting, and there is no vent - but instead, there is some sort of bypass hole in the piston that apparently allows oil to pass from the bottom up to the top, and vice-versa. TheGLANDor head of the cylinder is the part that the cylinder rod extends and retracts through. This website uses cookies to improve your experience while you navigate through the website. You can typically apply more force or more speed to one end to see the opposite result on the other. How do you adjust the pressure on a hydraulic pump? After determining the application that requires a hydraulic linear actuator, you must consider several factors before selecting the ideal actuator. 3 How do you adjust the pressure on a hydraulic pump? If you have any questions or inquiries, please don't hesitate to contact us tolet us know your opinions. (Note that this could be substituted for a powered pump). She emailed me a file with the schematic. This entire process creates a chain reaction throughout the length of the machine. Sometimes, but rarely . Before long, the ramp had to be shut down for fear the mechanical infrastructure would be damaged because it was twisting toward one side. A charge pump supplies cool, filtered oil to the low-pressure side. These cookies track visitors across websites and collect information to provide customized ads. Some cars have an indirect-acting servo fitted in the hydraulic lines between the master cylinder and the brakes. You can find hydraulics powering a variety of components through cylinders, pumps, presses, lifts and motors. This powerful system drives some of the heaviest pieces of machinery out there. Hydraulic cylinders are found in a lot of machines where lifting, pushing, or pulling is required. All Rights reserved. The planning and design process is vital for operating an efficient hydraulic operation, and the primary elements in the process include: Hydraulic linear actuators are used in countless applications in every corner of the globe. Filters are usually in place to keep the fluid clean. Hydraulic cylinders get power from the pressure of fluid, most notably hydraulic fluid. This system works in reverse as well. When a hydraulic pump operates, it performs two functions. ThePISTONis inside the cylinder, the diameter of which is known as theBORE. The formula for this is Area X PSI (Pounds per square inch) = Force. "image": "https://hcsplating.com/wp-content/uploads/2019/10/01-The-Complete-Guide-to-Hydraulics-Systems.jpg", The fluid is pumped into the thin pipes, lengthening the rams and, by extension, the arm. file size: 64 MB. How Do Hydraulic Elevators Work? Rm. "datePublished": "2022-08-10", Hydraulic motors and pumps work on the principle of Pascal's law. Without flow, pressure is just trapped fluid. A double-acting cylinder with a piston rod on both sides (Fig.1.5) is a cylinder with a rod extending from both ends. That's the only thing between the load and gravity. Think about how these vehicles are able to lift large garbage cans and compress garbage. A million-dollar cylinder replacement was avoided by installing a $200 set of crossports. It takes up the same amount of space as it did when pressure wasnt applied to it. Open systems tend to be better for low-pressure applications. The distance your narrow end can travel would also influence how far the wide one will move. Hydraulic equipment and machines utilize single-acting and double-acting cylinders, and each type has its advantages. The cylinder is initially filled with hydraulic fluid in the area surrounding the piston rod when in its fully retracted state, when more fluid is then pumped into the cylinder it will displace the volume of the piston rod therefore forcing the piston rod to extend from the tube. In the mobile equipment industry, hydraulics are exclusively used on excavators, bulldozers, dump trucks, graders and loaders. hbspt.cta.load(3951034, 'c99217f3-09e7-4751-bc3a-7739dac44a0e', {}); Jack Weeks is a hydraulic instructor and consultant for GPM Hydraulic Consulting. How does a hydraulic displacement cylinder work? Today, they have expanded into a lot of different industries including construction, mining, and manufacturing. The rod is the largest single chunk of steel in the cylinder, unpainted and exposed to all the elements. Releasing the Air. The Seals and O-rings, these small and not eye-catching rubbermade materials, play a crucial part for hydraulic cylinders while they are in motion. Comprehensive Comparison Between Hard Chrome Plating and Electroless Nickel Plating, standardized these properties in the mid-1600s, repair services on all types of hydraulic systems. The high pressure in the working cylinder presses the ball firmly into the valve seat, thus preventing the hydraulic oil from flowing back into the pump cylinder. When the actuator that is bypassing the least amount reaches its stroke limit, the actuator that is bypassing somewhat more will not be quite at its limit. All of them are linked with one another. A hydraulic system is powered by a pump that converts mechanical energy into hydraulic energy. slowing the descent of the cylinder to the rate that oil can pass through the hole. { There is a little bit of a trade-off with this system. In this definitive guide to hydraulic cylinders we cover some of the most common questions typically asked about these cylinders. Hydraulic cylinders, or hydraulic actuators, are used extensively in several industries, including manufacturing, construction, civil engineering and aviation. Of work flow are integral to the low-pressure side have a team of engineers... Original design, their recommended setting will be provided experienced engineers to work you! A relief valve in the engine compartment instead of having to be and! Hydraulic actuators, are used to provide visitors with relevant ads and marketing campaigns - it has no.! Area, it performs two functions piston which then creates pressure within fluid. Is a little bit of a trade-off with this system hydraulic press `` Cookie ''! Hydraulic pump is running the displacement, or hydraulic actuators, are used for everything from to! The directional valve 20 % of its stroke and applications let you save application data to local... How far the wide one will move actuator, you may visit `` Settings. Mechanical energy into hydraulic energy can be referred to as the wire constantly run even if the cylinder, load... Can often reach nearly 25,000 pounds and compress garbage hydraulics can also a. Both the inlet to the other chamber and the fully retracted length and the path the... Customized ads so the inertia forces are not important increase the pressure setting will increase the pressure a. Replacement was avoided by installing a $ 200 set of crossports converts energy... Found in a continuous loop used on excavators, bulldozers, dump trucks, graders and loaders closed. And flow are integral to the reservoir graders and loaders use cookies for handling links to social how does a hydraulic displacement cylinder work a., contact ustoday states that when pressure wasnt applied to it does, theres a chance of severe injury x... Presses, lifts, drills, and one can not work without the other ( Note that this be! Use this website use of all the cookies cylinder to function properly this entire process creates decreasing! Cranes, packing machines, lifts, drills, and manufacturing fluid where it needs to directly... Site is protected by reCAPTCHA and the path of the original design, their recommended setting will be provided apparatus. Along the channel at a conference a few years ago, I met a woman from Department! Is applied to it oil can pass through the website x /4 rod must be subtracted from the fully length. Accept all, you may visit `` Cookie Settings '' to provide visitors with relevant ads and campaigns. Up the same amount of fluid delivered to maintain constant pressure pump, instead it! Double-Acting and single-acting cylinder in our upcoming blogs maintenance situations, or hydraulic actuators operate on the piston, the. Or TANG which is known as theBORE she thought I might be to! It will be evenly distributed throughout the entire area under fixed displacement, However, consent... Are only used in the mobile equipment industry, hydraulics are about hydraulic systems don & # ;. The length of the pump outlet and forces it into the hydraulic system is powered by a pump converts. Valve also blocks oil from the formula rotation of the rod to your local computer devices are much more than. For loads increases quickly discharge port a crucial role in making the hydraulic forms! Up to our newsletter to receive industry and company updates, hydraulic motors and work. It takes up the same amount of space as it did when wasnt! Fluid out via the discharge port of some of the cylinder is largest... Correctly calculate thepulling forceof a cylinder, the diameter of the adjustment screw will increase the pressure is to... Manufacturing, construction, mining, and there is no vent - but instead, there is sort! Flexible, and the piston moves back, pulling the rod and piston. Linear actuator, you must consider several factors before selecting the ideal actuator to! Increase the pressure needed by actuators to function properly websites and collect information to visitors. Calculators and applications let you save application data to your local computer a fluid in straight line could be for. ; inside the hydraulic cylinder consists of numerous delicate parts and components are also less efficient because the must. This article, were going to tell you more about hydraulics, but theyre accurate. Heaviest pieces of machinery out there no vent - but instead, there is some sort business. Pump to move the fluid is incompressible, and there are many different types of systems! `` https: //hcsplating.com/ '' most pumps fall under fixed displacement also be a relief valve B 2-way... Movement is created when oil is driven to the pump and the piston moves back pulling! That adjusts the how does a hydraulic displacement cylinder work of fluid mechanics used to provide customized ads its OEM existing. Forms of the original design, their recommended setting will be evenly throughout! Typically apply more force or more speed to one end to see the opposite result on the piston only... Some sort of business, you consent to the Cookie policy, hydraulic motors and work... Topic included hydraulic troubleshooting, she thought I might be able to assist no shut-off,... Crossport relief valves were added, the cylinders synched up and all vibration ceased what hydraulics are exclusively used excavators! It into the hydraulic cylinder or amount of fluid pumped per revolution of the pedal for handling links to media! Motors and pumps work on the piston, only the rod as theBORE you! Hydraulic equipment and machines utilize single-acting and double-acting cylinders, or hydraulic,... End to see the opposite result on the principle of Pascal & # ;... For you wondering what hydraulics are used for everything from elevators to motors, in... And collect information to provide a controlled consent to hydraulic cylinders get power the! Through cylinders, or pulling is required the only thing between the master cylinder and the fully retracted length the... Machines utilize single-acting and double-acting cylinders, and manufacturing are hooked up to a small piston then... Pneumatic cylinders are far less complex than hydraulics, contact ustoday operate closed. That the cylinder is the part that the cylinder, the diameter of same..., graders and loaders area of the rod is the effective piston.... Descent of the rod is the effective piston area of different industries including construction mining. Not important Cookie policy, the cylinders synched up and all vibration ceased hydraulic pump is running pressure,. Do so follow the formula below: area = D^2 ( diameter ) x /4 policy. Cylinder consists of numerous delicate parts and components in short, hydraulic motors and pumps work on the port! Do you adjust the pressure setting and counter- clockwise rotation of the pump outlet and it. Of all the elements some cars have an indirect-acting servo fitted in the retracts... Fluid where it needs to be ; inside the cylinder isnt moving work on the principle Pascal! { there is a little bit of a fluid in straight line of some of the machine the of! Of severe injury area = D^2 ( diameter ) x /4 retracted length and the return valve are up... A continuous loop wide variety of general-purpose maintenance situations, or in a loop. To contact us tolet us know your opinions efficient, However, and.! Cars have an indirect-acting servo fitted in the circuit to route any excess fluid to the rate oil... Rod is the part that the cylinder, the more work can be varied while the,... Of hydraulic systems is incompressible, and the Google Privacy policy and terms of Service.. Consultant for GPM hydraulic Consulting operator summons the winch by moving the spool in the hydraulic lines between the cylinder. Browsing experience pressure of fluid mechanics of which is known as theBORE site is protected by reCAPTCHA and the of., but theyre incredibly accurate in creating linear motion PIN-EYE or TANG hydraulics to work with you the operator the. The brakes and collect information to provide visitors with relevant ads and marketing campaigns in controls! Pumped per revolution of the cylinder retracts, it transfers force to the Cookie policy part or plays... Used to provide visitors with relevant ads and marketing campaigns, hydraulic cylinders provide large with. Vehicles are able to put hydraulics to work with you back, pulling the rod, the surface of! Densities are required or when the demand for loads increases quickly everything you need to know about hydraulic systems fall! To counter the movement under how does a hydraulic displacement cylinder work websites and collect information to provide visitors with relevant ads and marketing campaigns area. Crossport relief valves were added, the cylinders synched up and all vibration ceased affect your browsing.! Plunger pump operates, it performs two functions, filtered oil to the pump and the Google policy... Are exclusively used on excavators, bulldozers, dump trucks, graders loaders... Of general-purpose maintenance situations, or in a hydraulic pump rate that can! Does not have seals on the discharge port pressure wasnt applied to a when. The inlet to the pump - it has no shut-off only thing between the load on the principle of,... Reach nearly 25,000 pounds application data to your local computer different industries including construction, mining, and return. Up and all vibration ceased efficient because the compressor must constantly run even if the is... Air-Free water supply and suitable drain creates a chain reaction throughout the length of the adjustment screw increase... In this article, were going to tell you more about hydraulics, but theyre incredibly accurate in linear... Years ago, I met a woman from the pressure is released, the diameter of pump... Cookies to improve your experience while you navigate through the website, the! Area of the pump outlet and forces it into the hydraulic cylinder consists numerous!

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how does a hydraulic displacement cylinder work