previous description
The adaptive control feedback provides sensory information on machining process variables such as spindle deflection or force, torque, cutting temperature, workpiece tool air gaps, material property variations, vibration amplitude, metal removable rate cost per volume of metal removed, and horsepower. The data is processed by an adaptive controller that converts the process information into feedback data to be incorporated into the machine control unit.
(Cad/Cam: Concepts And Applications, Yazar: Alavala, Page 403-404)
New description ( better)
For a machining operation the term adaptive control denotes a control system that measures certain output process variables and uses these control speed and or feed. Some of the process variables that have been used in adaptive control machining system include spindle deflection or force torque, cutting temperature, vibration amplitude and horsepower.
Nearly all the metal cutting variables that can be measured have been tried in experimental adaptive control systems. The motivation for developing an adaptive machining system lies in trying to operate the process more efficiently. The typical measures of performance in machining have been metal remove rate and cost per volume of metal removed. Adaptive control implies that the CNC system is responsive to adapt itself to operate at those machining parameters which result into higher productivity. A part programmer specifies cutting speeds, feed rates, depth of cut, etc. on the basis of knowledge and experience to achieve desired levels of manufacturing objectives, say, accuracy, surface finish and productivity.
(Lalit Narayan Et Al. , Computer Aided Design And Manufacturing , p281)
(Cad/Cam: Concepts And Applications, Yazar: Alavala, Page 403-404)
New description ( better)
For a machining operation the term adaptive control denotes a control system that measures certain output process variables and uses these control speed and or feed. Some of the process variables that have been used in adaptive control machining system include spindle deflection or force torque, cutting temperature, vibration amplitude and horsepower.
Nearly all the metal cutting variables that can be measured have been tried in experimental adaptive control systems. The motivation for developing an adaptive machining system lies in trying to operate the process more efficiently. The typical measures of performance in machining have been metal remove rate and cost per volume of metal removed. Adaptive control implies that the CNC system is responsive to adapt itself to operate at those machining parameters which result into higher productivity. A part programmer specifies cutting speeds, feed rates, depth of cut, etc. on the basis of knowledge and experience to achieve desired levels of manufacturing objectives, say, accuracy, surface finish and productivity.
(Lalit Narayan Et Al. , Computer Aided Design And Manufacturing , p281)
2 - Particulate Processes (manufacturing method) (manufacturing method) (22.33 cuma)
previous description
In particulate processing, the starting materials are powders of metals or ceramics. Although these two materials are quite different, the processes to shape them in particulate processing are quite similar. The common technique involves pressing and sintering, in which the powders are first squeezed into a die cavity under high pressure and then heated to bond the individual particles together.
(Fundamentals of Modern Manufacturing: Material, Processes, and Systems, Yazar:Mikell P. Groover, Page 13)
new description (better)
Particulate processes are characterized by the co-presence of continuous phase and a dispersed (particulate) phase, and are widely used in industry for the manufacturing of many high-value produscts. Examples include the crystallization of proteings for pharmaceutical applications, the emulsion polymerization reactions for the production of latex, the aerosol synthesis of titania powder used in the production of white pigments, and the thermal spray processing of nanostructured coatings. It is now well understood that the physice-chemical and mechanical properties of materials made with particules depend havily on the characteristics of the corresponding particle size distribution. This fact, together with recent anvances in dynamics of infinite-dimensional systems and nonlinear control theory, has motivated extensive research on model-based control of particulate processes using population balances to achieve tight control of particle size distributions.
(Panagiotis D. Christofides, Model-Based Control of Particulate Processes, p xix [preface])
3 - Electrostatic fluid bed (manufacturing) (cumartesi 13.05)
no older description
new description
In a modification of the fluid bed technique, the product to be coated, instead of being preheated, is passed over the bed, and the powder is attracted to it by a static charge. Then it is passed through a heating oven to fuse it into another finished coating. This process can be used for either discrete or continious products.
(Emil Raymond Riegel, James Albert Kent, Kent and Riegel's Handbook of Industrial Chemistry and Biotechnology, Volume 1, p680)
4 - Peel Test (inspection) (cumartesi 13:25)
previous description
Peel tests is the most common method for detemining of relative adhesion of sealent joint.Most peel test are conducted using constant peel speed and measuring the peeling force.
(Klosowski F.M.,Science and technology of building seals, sealants, glazing, and waterproofing,p.108)
new description
The peel test is mostly used to characterize the adhesion of tapes or films on substrates. A bonded assembly of two adherents is prepared under specific conditions using the adhesive under test. The adherents are then pullend apart at a substantially steady rate and angle, starting at the open end of the bond, in such a way that separation occurs progressively along the length of the bonded adherents. (Recommended dimensions of the bonded surface 25mm width, length of 150mm by ISO8510-1[23]). From the curve of the force versus grip separation the average peel force is determined. The force per width of bonded area is evaluated.
(Manfred Stamm, Polymer Surfaces and Interfaces: Characterization, Modification and Applications, p150)
5 - Wedge Test ( inspection ) (cumartesi 13.36)
previous description
In particulate processing, the starting materials are powders of metals or ceramics. Although these two materials are quite different, the processes to shape them in particulate processing are quite similar. The common technique involves pressing and sintering, in which the powders are first squeezed into a die cavity under high pressure and then heated to bond the individual particles together.
(Fundamentals of Modern Manufacturing: Material, Processes, and Systems, Yazar:Mikell P. Groover, Page 13)
new description (better)
Particulate processes are characterized by the co-presence of continuous phase and a dispersed (particulate) phase, and are widely used in industry for the manufacturing of many high-value produscts. Examples include the crystallization of proteings for pharmaceutical applications, the emulsion polymerization reactions for the production of latex, the aerosol synthesis of titania powder used in the production of white pigments, and the thermal spray processing of nanostructured coatings. It is now well understood that the physice-chemical and mechanical properties of materials made with particules depend havily on the characteristics of the corresponding particle size distribution. This fact, together with recent anvances in dynamics of infinite-dimensional systems and nonlinear control theory, has motivated extensive research on model-based control of particulate processes using population balances to achieve tight control of particle size distributions.
(Panagiotis D. Christofides, Model-Based Control of Particulate Processes, p xix [preface])
3 - Electrostatic fluid bed (manufacturing) (cumartesi 13.05)
no older description
new description
In a modification of the fluid bed technique, the product to be coated, instead of being preheated, is passed over the bed, and the powder is attracted to it by a static charge. Then it is passed through a heating oven to fuse it into another finished coating. This process can be used for either discrete or continious products.
(Emil Raymond Riegel, James Albert Kent, Kent and Riegel's Handbook of Industrial Chemistry and Biotechnology, Volume 1, p680)
4 - Peel Test (inspection) (cumartesi 13:25)
previous description
Peel tests is the most common method for detemining of relative adhesion of sealent joint.Most peel test are conducted using constant peel speed and measuring the peeling force.
(Klosowski F.M.,Science and technology of building seals, sealants, glazing, and waterproofing,p.108)
new description
The peel test is mostly used to characterize the adhesion of tapes or films on substrates. A bonded assembly of two adherents is prepared under specific conditions using the adhesive under test. The adherents are then pullend apart at a substantially steady rate and angle, starting at the open end of the bond, in such a way that separation occurs progressively along the length of the bonded adherents. (Recommended dimensions of the bonded surface 25mm width, length of 150mm by ISO8510-1[23]). From the curve of the force versus grip separation the average peel force is determined. The force per width of bonded area is evaluated.
(Manfred Stamm, Polymer Surfaces and Interfaces: Characterization, Modification and Applications, p150)
5 - Wedge Test ( inspection ) (cumartesi 13.36)
previous description
Wedge tests are very popular for evaluating adhesive bond durability.This test is very simple to conduct and very cost effective. The wedge test has been used extensively as a screening tool to evaulate several surface pretreatments for titanium adherends.Based on these screening tests two surface treatments,the phenylethynyl trimethyl silane (PS) treatment and the chromic acid anodization (CAA) were chosen for this study.
(Zureich A.,High temperature and environmental effects on polymeric composites, Volume 2,p.150)
new description(better)
The so called "wedge test" according to D3762 (ASTM), for example, simulates (in qualitative manner) the forces and effects on an adhesive bonded joint at the metal-adhesive primer interface. This test has proven to be highly reliable for determining and predicting the environmental durabiliry of adherent surface preparations. The results obtained may be well correlated to the service performance of the adhesive in a way that is much more reliable than conventional lap shear or peel tests.
At the beginning of the test a wedge is driven into the bond-line of a flat-bonded specimen, thereby creating a tensile stress in the region of the resulting crack tip (Figure 7.8). The stressed specimen is exposed to an aqueous environment, usually at an elevated temperature, or to an appropriate environment relative to the use of the bonded structure in the later application. The resulting crack growth with time and failure modes are evaluated later. Variations in the adherent surface quality are easily observable when the specimens are forcibly, if necessary, opened at the end of the test.
(Walter Brockmann,Paul Ludwig Geiß9,Jürgen Klingen,K. Bernhard Schröder, Adhesive Bonding: Materials, Applications and Technology, pp133,134)
(Zureich A.,High temperature and environmental effects on polymeric composites, Volume 2,p.150)
new description(better)
The so called "wedge test" according to D3762 (ASTM), for example, simulates (in qualitative manner) the forces and effects on an adhesive bonded joint at the metal-adhesive primer interface. This test has proven to be highly reliable for determining and predicting the environmental durabiliry of adherent surface preparations. The results obtained may be well correlated to the service performance of the adhesive in a way that is much more reliable than conventional lap shear or peel tests.
At the beginning of the test a wedge is driven into the bond-line of a flat-bonded specimen, thereby creating a tensile stress in the region of the resulting crack tip (Figure 7.8). The stressed specimen is exposed to an aqueous environment, usually at an elevated temperature, or to an appropriate environment relative to the use of the bonded structure in the later application. The resulting crack growth with time and failure modes are evaluated later. Variations in the adherent surface quality are easily observable when the specimens are forcibly, if necessary, opened at the end of the test.
(Walter Brockmann,Paul Ludwig Geiß9,Jürgen Klingen,K. Bernhard Schröder, Adhesive Bonding: Materials, Applications and Technology, pp133,134)
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