KM/ Stainless steel air bellows Single acting Ø to mm Stainless steel end plates Frictionless operation No maintenance or lubrication Ideal for short stroke, high-force applications High isolation level for vibrating machines Very easy to install no alignment problems Technical data Medium: Compressed air, non-lubricated Operation: Single acting Operating pressure: max. Operating temperature: - to +7 C for KM/ (Standard) -5 to +9 C for TKM/ (Butyl) - to +5 C for EKM/ (Epichlore) Nominal diameters:,,, / inches Strokes: From to mm max., depending on diameters and number of convolutions Materials End plates: stainless steel. Stud: stainless steel. Central ring: stainless steel. Bellow: KM/: fabric reinforced NR-, SBR-, BR-compound rubber TKM/: fabric reinforced Butyl EKM/: fabric reinforced Epichlore Important instructions: The design of these air bellows allows an operation at an angle of 5 to 5. The top and bottom plate can be out of alignment, depending on the height of the air bellow and the number of convolutions. To avoid damage mechanical stops at both end positions have to be used. To return air bellows to their minimum height an external return force must be used. The thrust depends directly on the height of the air bellow: When height increases the thrust decreases. As the outside diameter varies in operation there must be enough clearance around the air bellow Ordering information See page / Our policy is one of continued research and development. We therefore reserve the right to amend, N/UK..7.
KM/ Alternative air bellows Symbol Model Description Dimensions Page KM/ Standard Ø to / inch (Ø to mm) TKM/ Butyl Ø to / inch (Ø to mm) EKM/ Epichlore Ø to / inch (Ø to mm) Options selector KM/ Air bellow materials NR-, SBR-, BR-Materials High temperature (Butyl) Extreme temperature (Epichlore) Substitute None T E Number of convolutions Substitute Nominal diameters (inches) Substitute / Note: Please fill in only the numbers of digits required, e.g. KM/ Ordering example Air bellows To order a stainless steel air bellow in standard rubber material, a nominal diameter of inches and convolutions quote: KM/ Warning These products are intended for use in industrial compressed air systems only. Do not use these products where pressures and temperatures can exceed those listed under Technical Data. Before using these products with fluids other than those specified, for non-industrial applications, life-support systems, or other applications not within published specifications, consult NORGREN. Through misuse, age, or malfunction, components used in fluid power systems can fail in various modes. The system designer is warned to consider the failure modes of all component parts used in fluid power systems and to provide adequate safeguards to prevent personal injury or damage to equipment in the event of such failure. System designers must provide a warning to end users in the system instructional manual if protection against a failure mode cannot be adequately provided. System designers and end users are cautioned to review specific warnings found in instruction sheets packed and shipped with these products. N/UK..7. Our policy is one of continued research and development. We therefore reserve the right to amend, /
KM/ Basic dimensions KM/ to KM/ A 5,5 ø N M B B F D A G / Installation diameter min. Installation height min. Installation height max. Stroke Table Model Nominal diameter Stroke Installation height Weight (inch) x B min. B max. Air bellows (mm) (mm) (mm) Ø A Ø D Ø F Ø N (kg) KM/ x 5 5 5, KM/ x 75 75 5 5 5 7, KM/ x 5 5,5 KM/ x 5 75 7 9,7 KM/ x 7,9 KM/ x 5 5 5, KM/ x 5 75 5 5, KM/ x 5 5, KM/ / x 5 5 75 95 5, KM/ / x 75 75 5 9, KM/ / x 5,5 / Our policy is one of continued research and development. We therefore reserve the right to amend, N/UK..7.
KM/ Thrust (at,,, ), volume (at ) KM/ KM/ 5,5 5 5, 5,5 5, bar 5,5 5 bar 5 75 5 5 KM/ KM/ KM/ 5 7 5 5 5 5 7 5 5 bar 5 5 5 5 bar bar 5 5 5 5 5 75 5 5 5 5 5 Thrust (N) N/UK..7. Our policy is one of continued research and development. We therefore reserve the right to amend, /
KM/ Thrust (at,,, ), volume (at ) M/ KM/ KM/ 5 5 5 bar bar bar 5 5 75 5 5 5 5 5 KM/ KM/ KM/ 7 5 bar 7 5 bar,5, 7,5 5,,5 7 5, 7,5 bar 5, 7 5 5 9 75,5 75 5 5 5 5 5 5 Thrust (N) / Our policy is one of continued research and development. We therefore reserve the right to amend, N/UK..7.5
KM/ Calculation of compact air bellows used as actuators Datasheet a) Total weight to be lifted: F =......... kg m/s =......... (N) b) Number of air bellows: n =......... c) Thrust per air bellow: f = F = =......... (N) n d) Operating pressure: P =......... (bar) e) Required stroke: S =......... (mm) f) Vertical space: Xv =......... (mm) g) Horzontal space: Xh =......... (mm) h) Operating temperature: T =......... ( C) i) Operation angle: a =......... ( ) j) Out of alignment: A =......... (mm) k) Chemical resistance......... Important instructions Thrust: The thrust depends on the height of the bellow. When height increases the thrust decreases. Stops: To avoid damage when the bellow is compressed or extended mechanical stops at both end positions have to be used. Clearance: There must be enough clearance around the Air Bellow. Table : thrust, installation height, retracting force Model Nominal Ø Stroke Installation height Thrust Retracting force to Installation height Thrust (inch) x B min. at reach min. height B max. at Convolutions (mm) (mm) (N) (N) (mm) (N) KM/ x 5 55 KM/ x 75 75 75 5 5 55 KM/ x 5 5 5 9 KM/ x 5 75 5 5 KM/ x 5 KM/ x 5 5 5 5 KM/ x 5 75 5 55 KM/ x 9 KM/ / x 5 5 57 75 55 KM/ / x 75 75 95 9 9 KM/ / x 55 9 Operation angle Out of alignment α H H A Table Model Nominal Ø Height H (mm) at Height H (mm) bei (inch) x Convolutions a = 5 a = a = 5 a = a = 5 A = mm A = mm A = mm A = mm A = 5 mm KM/ x -5 7-5-5 7-95 KM/ x 9- -5-5-9 95-95- 5- -95 KM/ x -5 7-5 -5 7-5 - 9-5 KM/ x 95-5-5 5-5 55-5 5-5-75 5-5 7-5 KM/ x 5-9 5-7 -5 5-9 - -5-5 -5 KM/ x -5 75-5 9-5 7-5 - 9-5 KM/ x -55-5 5-5 -5 5-7 - 5-5 75- KM/ x -75-5- 5-75-5 95-75 5-5-5 KM/ / x 5-5 5-5 5-95-5 5-5 KM/ / x 5-5-9 5-75 7- - - 5-5 5-5 KM/ / x - -9-7 -5 5-5-5 5- -5 N/UK..7. Our policy is one of continued research and development. We therefore reserve the right to amend, /
KM/ Selecting air bellows Example: used as actuators A kg conveyor carrying a 55 kg pallet needs to be lifted by mm (stroke) in order to transfer the pallet to another level. Four () air bellows should be used. The available operating pressure is 5 bar. The operating temperature is C. There is a 7 mm square space to house each air bellow. Compression and extension stops are provided. The air bellows have to be mounted between in a space which are 5 mm apart. During the lifting operation the conveyor may tilt in the second half of the stroke by a max. of 9. Step : Fill in and complete the datasheet a) Total weight to be lifted: F = ( kg + 55 kg) m/s = 55 (N) b) Number of air bellows: n = c) Thrust per air bellow: f = F = 55 N = 75 (N) n d) Operating pressure: P = 5 bar e) Required stroke: S = mm f) Vertical space: Xv = 5 mm g) Horizontal space: Xh = 7 mm h) Operating temperature: T = C i) Operation angle: a = 9 j) Out of alignment: A = mm k) Chemical resistance: normal environment Step : From table.. and.. (page + ) air bellows have to be selected, that have a min. mm stroke and clearance around the air bellows smaller than Xh = 7 mm. We select: KM/, KM/, KM/ and M/ Step : Calculate the total height at which the Air bellow should be used, see step : Vertical space: Xv 5 mm Stroke: S mm Total height: 5 mm By refering to the total height of 5 mm and the vertical space of 5 mm, only KM/ (installation height to 95 mm) and KM/ (installation height to 5 mm) can be used from table. to. (datasheet and ) Step : Check the thrust at at a height of 5 mm. From the charts in the datasheet and 5 we can see that: Step 5: Check the angle acceptance when the air bellow can tilt during the second half of the stroke between 5 and 5 mm by approx. from table (page ). At 9 we are well within the limits i) KM/ can sustain an angle of 9 between 95 and mm Only KM/ can be used in this application, Step : Check all remaining parameters h) At C Standard rubber material (- to +7 C) can be used j) No horizontal miss-alignment k) No special chemical resistance is required Result: KM/ is the chosen air bellow, because it meets all requirements. 5 5 5 5 KM/ will provide 5 N at. To get the figure for 5 bar, we have to calculate: 5 N 5 = 75 N at 5 bar 5 bar 75 5 5 Conclusion: Both Air Bellows can provide the required thrust of 75 N. / Our policy is one of continued research and development. We therefore reserve the right to amend, N/UK..7.7
KM/ Calculation of compact air bellows used as vibration isolators Datasheet a) Total weight to be isolated: F =......... kg m/s =......... (N) b) Number of air bellows: n =......... c) Thrust per air bellow: f = F = =......... (N) n d) Operating pressure: P =......... (bar) f) Vertical space: Xv =......... (mm) g) Horizontal space: Xh =......... (mm) h) Operating temperature: T =......... ( C) k) Chemical resistance:......... m) Isolation rate: I =......... (%) o) Airspring natural frequency fn =......... (Hz) p) Excitation frequency fe =......... (Hz) Important instructions Air Bellows with two convolutions will provide better isolation because of the greater volume of air in comparison to air belows with one convolution. Air bellows used for vibration isolation should be operated at a»vibration height«. This height is the result of tests and represents the optimum height where the air bellow gives the best performance. The airspring natural frequency (fn) remains nearly constant at the»vibration height«. An increase of the height will result in less isolation, a lower height may influence the horizontal (lateral) stability. The optimum pressure for vibration isolation is from to ( to 9 psi). The lower the airspring natural frequency (fn) of an Air Bellow the better the vibration isolation. The lateral stability of air bellows decreases with the number of convolutions. It is important to note: air bellows with three convolutions should not be used without consulting Norgren. Ideally air bellows should be located at the same horizontal plane (at the same height) as the centre of gravity of the machine in order to be vibration isolated. For the purpose of calculation the following assumptions have been made:. Vibrations are all vertical. The excitation frequency (fe) varies along a sine curve. The object and its base are rigid Table : Pressure, vibration height, thrust, volume, stiffness, airspring natural frequency, isolation rate Model Nominal Ø Pressure Vibration Thrust Volume Stiffness Airspring Isolation rate (inch) x height natural frequency I (%) Convolutions (bar) (mm) (N) (l) (N/cm) fn (Hz) at Hz and KM/ x 75,9 79, 9, 5,9,77 9,7 KM/ x 55,5, 95,,,95 9, KM/ x 5,5 7,5 9, 5,9 5, 9,5 KM/ x 9, 5, 9, 55,7 7,75 9, KM/ x 5 5,,5 9, 55 5, 5, 9,7 KM/ x 5 9,5, 9,5 5 9,5 5,7 9,7 KM/ / x 5,97 559, 9, 9 9, 7, 9, KM/ / x 5 7,, 97, 5 5, 7, 97, KM/ / x 7 5,97,5 9, 7 5 7,, 9, Values for air bellows with three convolutions are not given as they cannot be used as vibration isolators. N/UK..7. Our policy is one of continued research and development. We therefore reserve the right to amend, /
KM/ Example for selecting compact air bellows used as vibration isolators A hydraulic power unit with an excitation frequency (fe) between and cycles/min (= Hz to 5 Hz) must be vibration isolated. The total weight of the power unit is kg. The supporting area under the unit is, m x, m. Step : Fill in and complete the datasheet a) Total weight to be isolated: F = kg m/s = N b) Number of air bellows: n = c) Thrust per air bellow: f Step : Take the Air Bellow with the lowest airspring natural frequency fn =,7 Hz in order to get the highest isolation rate refering to fe min. = Hz. Air Bellow KM/ is chosen. Step : Calculate the isolation rate (I) of the KM/ by using the formula: The operating temperature is 5 C. The space for the installation is mm high. Four air bellows will be used. The max. operating pressure is. A minimum of 97% vibration isolation has to be reached. = N = 5 N d) Operating pressure: P = f) Vertical space: Xv = 5 mm g) Horizontal space: Xh = mm h) Operating temperature: T = 5 C k) Chemical resistance normal environment m) Isolation rate: I = 97% o) Airspring natural frequency fn =... Hz p) Excitation frequency fe = min. Hz, max. 5 Hz Two types of air bellows are chosen. Each one has to carry 5 N at the vibration height. From table (page ) we select:. KM/ 5 N at, Hz airspring natural frequency (fn). KM/ 5 N at,5 Hz airspring natural frequency (fn). KM/ 5 N at,7 Hz airspring natural frequency (fn) Formula: I = - ( fe ) - fn Load (fe) Example: I = - ( ) -,7 = - 5, =,99 (fn) (fn) I = 99,% Step : Check all remaining parameters e) The installation height of the air bellow KM/ is between B min.= 5 mm and B max.= mm (table ). The vertical space for installation is mm. The vibration height at which the air bellows operates best is mm (table ). f) The clearance around the air bellows. The horizontal space for installation is mm for each air bellows. The clearance around the air bellow is 5 mm (table.). fe = Excitation frequency of load fn = Airspring natural frequency h) At 5 C Standard rubber material (- to +7 C) can be used. g) No special chemical resistance is required. i) Isolation rate at Hz and is 9,7% (table ). At Hz and I= 99,% is reached. Result: x KM/ compact air bellows are chosen. They will provide 99,% vibration isolation. / Our policy is one of continued research and development. We therefore reserve the right to amend, N/UK..7.9