3 factors decide the performance of cylinder

//3 factors decide the performance of cylinder

3 factors decide the performance of cylinder

Last week we talk about the pneumatic cylinder and it’s advantage, how rod style air cylinder works, today we will discuss about what ‘s main factors decide the performance of cylinder. Here comes the following factors:

Force output

Key selection criterion is how much force a cylinder generates. Determine this from the air pressure and bore size.(attach the theory force sheet)

Designers can calculate cylinder force by multiplying the effective piston area by the working pressure. The effective area for push force is the cylinder bore. For pull, it’s the bore area less the cross-sectional area of the piston rod.

Theoretical push force is:

F = π(D2/4 )P

where F = force, lb; D = cylinder bore, in.; and P = pressure, psi.

Theoretical pull force is:

F = π(D2/4 – d2/4)P

where d = piston rod diameter,in

For single-acting cylinders with a spring Force, the calculations get more complicated . The force opposing the push or pull increases as the stroke progresses. In practice, manufacturers’ catalogs often list push and pull values for both double-acting and single-acting cylinders, simplifying calculations for users.(attach the theory force sheet)

When estimating the relative force of cylinders with different bore sizes, remember that thrust increases with the square of the diameter. In other words, doubling the bore will quadruple the thrust.

Speed

Speed affects productivity, longevity, and controllability. The Calculation as below

s = 28.8q/A

where s = speed, ips; q = airflow in standard cubic feet/minute; and A = piston area

Other factors that might affect speed include port sizes, inlet and exhaust flow through control valves and tubing sizes.

With any fixed combination of valve, cylinder, pressure, and load, it is usually necessary to have adjustable control valve over cylinder speed. Flow controls at the cylinder ports let users turn speed to their application.

Air consumption

Calculating a cylinder’s air consumption is often necessary on fast-cycling equipment to ensure enough supply air is available or air starvation at critical times will cause performance to suffer.

QA = (A1+A2) x L x (P +1.033)/1.033 x 10 -3

QB = 2 x A3 x LH x (P +1.033)/1.033 x 10 -3

Qn = (QA + QB) x n

Qn: Air consumption of Cylinder actuating/ each time (L/min) 

QA:Air volume for cylinder actuating to and back/ each time (L/min) 

QB:Air Consumption Valume of Accessories(Valve the Cylinder)(L/min))

A1:Push Side Pressured Area (cm2) 

A2:Pull Side Pressured Area (cm2) 

A3:ID of Connecting tube (cm2)

L:Stroke of cylinder (cm)

LH:Length of tube(cm)

P:Operating Pressure (kgf/cm2)

n:Operating Frequency

Theory force output sheet:

Cylinder Inside Diameter32324040505063638080100100125125160160200200
Extemal Diameter Piston Rod121216162020202025252525323240404040
OperationDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble ActingDouble Acting
OperationExtrusion sidePull sideExtrusion sidePull sideExtrusion sidePull sideExtrusion sidePull sideExtrusion sidePull sideExtrusion sidePull sideExtrusion sidePull sideExtrusion sidePull sideExtrusion sidePull side
Compression Area(cm2)8.046.912.5610.5516.4931.1728.0328.0345.3678.5373.62122.7114.6201188.4314.2301.4301.4
Air Pressure (Kgf/cm2)8.046.912.5610.5519.6316.4931.1731.1750.2645.3678.5373.62122.7114.6201188.4314.2301.4
Air Pressure (Kgf/cm2)16.0813.825.1221.139.2632.9862.3462.34100.5290.72157.06147.24245.4229.2402376.8628.4602.8
Air Pressure (Kgf/cm2)24.1220.737.6831.6558.8949.4793.5193.51150.78136.08235.59220.86368.1343.8603565.2942.6904.2
Air Pressure (Kgf/cm2)32.1627.650.2442.278.5265.96124.65124.65210.04181.44314.12294.48490.8458.4804753.61256.81205.6
Air Pressure (Kgf/cm2)40.234.562.852.7598.1582.45155.85155.85251.3226.8392.65368.1613.5573100594215711507
Air Pressure (Kgf/cm2)48.2441.475.3663.3117.7898.94187.02187.02301.56272.16471.18441.72736.2687.612061130.41885.21808.4
Air Pressure (Kgf/cm2)56.2848.387.9273.85137.41115.43218.19218.19351.82317.52549.71515.34858.9802.214071318.82199.42109.8
Air Pressure (Kgf/cm2)64.3255.2100.4884.4157.04131.92249.36249.36402.08362.88628.24588.96981.6916.816081507.22513.62411.2
Air Pressure (Kgf/cm2)72.3662.1113.0494.95176.67148.41280.53280.53452.34408.24706.77662.581104.31031.418091695.62827.82712.6
By |2016-12-10T10:00:19+00:00January 29th, 2016|101 Knowledge|0 Comments