Test Procedures and Definitions
Assisting the Blanket Industry
Test procedures
Test procedures
Spring versus Dashpot: So apparently similar Balls with so completely different reactions.
The Happy Ball jumps several times, as it would be normally expected from elastic rubber.
The Unhappy Ball reaches the floor with an even slightly higher Kinetic Energy.
Even so, it does not gather enough free Potential Energy to jump and initiate an oscillatory movement.
Inline Thickness Control contributes to a new standard of Printing Blankets Conversion.
Dead-weight Thickness Measurement Equipment is an integral part of the blanket format Identification Station, for in-line thickness tolerance checking.
Constructive – Destructive Interference: The resultant of two oscillatory movements is the vectorial addition of the two oscillations.
Let us assume graph 1 is the Applied Oscillation and graph 2 is the Reaction Oscillation. Graph 3 is the resultant.
The above figures – left and right – show two extreme cases when the oscillations are in step (phase) or in counter-phase.
The phase angle between Applied and Reaction Oscillations results from the Response Delay Time and Response Frequency.
In fig.1 the Resultant Amplitude is larger than the Applied Oscillation, while in Fig.2 it opposes the Applied Oscillation.
If Applied and Reaction Oscillation Frequencies are different Resultant Curve is distorted (no longer sinusoidal).
System Damping Degrees: Conditions the number of cycles that an oscillatory system, not connected to an oscillation source, is able to complete.
Curve 3 shows the reaction of a lightly damped oscillatory system to an excitation pulse. It will complete a few oscillation cycles through its equilibrium point before it comes to rest.
Curve 2 describes an oscillatory system that, once excited, returns to its resting position as quickly as possible, without completing any oscillation cycle, typical of a critically damped system.
Curve 1 depicts the behaviour of a heavily damped oscillatory system. Once excited it returns to its resting position more slowly than a critically damped system. A higher damping degree will mean an increasingly slower return to rest.
String – Natural Frequency: Unlike Springs that oscillate axially, Strings’ vibration is transverse to its length.
Selected Fret – #4 in picture – determines effective string length and respective response frequency.
In a String, material, geometrical proportions and tension determine its Response Frequency.
In a fabric ply, fill threads will eventually be “active”, acting as frets whenever energetic Warp Thread prestress is present.
When two adjacent fill threads become “active”, they define extremely high pitched warp thread string-segments.
Grooved Horn Tip: Pressure concentrates at Horn Crests.
Even a low energy transfer is enough to efficiently melt continuous glue lines.
Specific End-Use Horns: Horn design varies, not only with its End-Use, but also with its Service Frequency.
Speed of propagation equals the Frequency times the Wavelength.
Speed varies with the propagation media.
Half Wavelength Horns
Top – 30 kHz Cutting Horn
Bottom – 40 kHz Welding Horn
Hard Metal Blade tip affords a perfect cut with virtually no wear.
When Ultrasound fed, high cutting speeds become possible with negligible Blanket reaction.
It is easy to obtain vibration amplitudes well in excess of 0.1 mm.
Ultrasound Cutting Tool reduces Format distortion, significantly contributing to professional Blanket Conversion.
Horn fitted with Hard Metal Blade Tip
Vortex Working Principle – Compressed Air Source unfolds into a Glacial Cold Air output plus a Hot Air residue.
Intense and spot ultrasound horn tip cooling together with full “cold operation” efficiency. That’s Vortex magics.
Stationary Vortex Hi-Speed Engine with Hot and Glacial Cold Air Outlets
Quality Factor Q – The Ratio between the peak of reactive energy stored by the system and the energy dissipated during each cycle of oscillation defines Q.
With the oscillatory source disconnected, in a low Q factor System, oscillation amplitude will dampen and die out rapidly.
Too high a load for the available Oscillatory Power or geometrical changes will lower System Q factor.
Horn shape variety enables to apply the ideal unit according to its end use application and particular load geometry.
As the name suggests, Horn design includes often an amplification factor, increasing vibration amplitude delivered to the load.
Ultrasound applications range from industrial welding and cutting, or cleaning, to medical and nano technology.
Ultrasound Boosters, as the name suggests, act like Resonance Boxes. They decisively contribute to improve the Quality Factor, Q, of the oscillatory system.
The left and right sides are not symmetric. When the Converter connects to the left side, the output vibration amplitude doubles.
Blanket Metal Terminals, usually known as Bars, enable swift blanket cylinder dressing on offset presses.
Tape application CPanel enables control and optimisation on glue tape fitting operation.
Control Panel enables prompt management of 11 glue operation parameters, of which we highlight:
Blank and Glue Tape Models, Energy transferred and Pressure applied and gluing speed.
Other variables are digitally programmable directly on the data base.
Abrupt Frontier – Depending on the particular instance, Blanket Format edges represent solid/gas, or solid/liquid frontiers.
Ambient Moisture during Blanket storage and use, Ink and blanket Washes subject blanket surfaces and edges to degradation.
Ultrasound Converters result from a stack of special ceramic disks, using the Piezoelectric effect.
In a somewhat similar way to a resonant helical spring, the Converter disk stack is subject to axial length variations.
However, ceramic Converter’s resonance takes place at ultrasound high frequency with extremely
minute amplitude.
Except for the reaction delay, its response is in step with the electric oscillator’s frequency.
An Ultrasound Generator converts the mains 50-60 Hz alternating current into a Source of
High Frequency Power. It assists Barred Blanket production.
Usual Frequencies fall within the 20 to 40 kHz range.
Ultrasound Welding Principle comprises several components:
Ultrasonic Power Supply Generator, Converter, Horn and Load.
The Booster (also shown in the arrangement), usually included to improve resonant system’s efficiency.
Glue Activation Control-Panel has a generous number of different glue activation cycles capability.
Bar geometry and end use conditions set heat cycle temperature and time.
Glue-Activation-Press Control Panel enables the use of the best heat cycle and duration.
It does also register total and still missing number of activation cycles for Quality Assurance purposes.
Pretensioning implies Distortion – They are just Cause and Consequence, inherent to blanket’s carcass fabrics concept behind its production.
Distortions in the Around and Across directions will necessarily be different.
It is possible to minimize internal tension effects, generated by the warp thread length equalization operation taking place during cloth manufacture stage.
Bar Press Control Panel has up to 100 different press cycles capacity.
Each register enables to program a wide range of press parameters, to meet specific Bar requirements.
Steel Bar Model description includes sheet gauge and nominal closing thickness.
The image refers to a 0,5 x 12 x 12 mm stainless steel bar designed to close with 2,25 mm.
Personalisation – Custom executions – Each customer has its particular needs.
Base Execution defines best Raw Material origin and the Cutting Method.
It does also include Product Identification and Blanket dressing Procedure, format Corner Trimming and correct Bar details.
Personalisation affects up to 14 Conversion Operations adding another 18 new Parameters and 8 Custom Instructions to meet particular requirements.
Blanket Cutting Control Panel coordinates the seamless performance of four independent axes and an enlarged parameter set for confined blanket material cutting.
Picture shows Cutting Table Control Panel in its Manual Mode Menu.
Semi-automatic mode has an up-to 8 stage sequential cutting capability from customer’s built-in Data Base.
Semiautomatic Cutting Table assisted by Ultrasound equipment.
Two Independent Processors digitally control Cutting Head Travel and the respective Depth.
Laser precision equipment warrants Parallelism from the movable stop to the cutting track.
Blanket Cross-Section and Surface Texture give an initial assessment of its response consistency.
Series 710/1,70 mm Blanket Cross-Section Structure and Surface Texture.
Please note the rectified free surface of the Compressible Layer’s Sub-Assembly.
Blankets Package – Narrow-Gap-Web – provides additional moisture protection. It does also reduce handling to the bare minimum until cylinder dressing.
According to PCKOUT instruction, surface rubber faces outwards with bar edges protected by foam tape.
A plastic sleeve, duly sealed at both ends, covers each format.
Hard cardboard boxes protect each set of 4 formats, individually protected by internal cardboard separators.
Web Blankets Package: Follows strict procedures for ease of press cylinder dressing.
For WEB applications rubber surface faces outwards, duly protected by paper.
Whenever the bars have sharp edges, these must be protected by plastic foam tape.
Hand Tool Insulation Tubes incorporated in mass produced Electric Power Tools.
Constant quality filament wound double insulation tubes used in Black & Decker Hand Tools for added operator protection.
Local Owens Corning factory used this feature to optimise the silane grade for epoxy resins added during Fibreglass extrusion.
Effective Silane use transfers the mechanical stresses applied to the laminate bulk to its fibreglass reinforcement.
Densified Wooden Laminate obtained following compression, with a heating/cooling cycle.
Monitoring veneer moisture is crucial during the complete production cycle.
Magnified view of unidirectional goiabão laminate, 37-layer sample with 2 cm thickness.
Laminate developed for shuttle driving arms of textile weaving looms.
Stator DMC Insulation Caps – Dough Moulding Compound Technology applied into a hot press mould.
DMC (Dough Moulding Compound) – Insulation caps form a clearly visible orange circle on generator’s stator.
They represent just a small portion of the ~10 Tons insulating laminates supplied to every BBC and Siemens generator.
Salt Water Injection Pipe with Filament Winding technology used in oil fields to achieve the required high pressure.
Section of FRP Filament wound pipe including connecting Spigot with O-ring Seal groove, Connection Sleeve and stainless steel cable Lock.
Pipe specially developed for Petrobras.
