AllenWeb
AllenWeb
Jun 98
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Accumulators (bladder,
piston)Actuators (rotory)
Adapters
Amplifiers
Bearings (composite)
Clamping Systems
Compressors (air)
Connectors
Control Panels (electrical)
Controllers & Positioners
Couplers (hydraulic)
Cylinder Tubing (composite)
Cyliners (hydraulic,
multi-power, pneumatic)
Drives (electronic)
Filters (hydraulic, all
types) Filtration (carts
& systems) Fittings
(hydraulic, all types) Gages
(instrumentation) Grippers
(parrallel) Headers
Heat Exchangers
Hoses (hydraulic, pneumatic)
Hydraulic Flanges
Hydraulic Fluids
Industrial Nuts
Intensifiers
Junction Blocks
Manifolds & Subplates
Motors (air)
Motors (brushless, motor parts,
hydraulic) Nozzles
O-Rings
Orifices
Packings
Plugs (protectors and expansion)
Positioners
Power Units/Packs
Presses (air)
Pressure Transmitters
Protectors (cable, hoses, thread,
cable) Pumps (air operated,
hydraulic, vacuum)
Regulators (pressure)
Reservoirs Restrictors
Seals (sealing systems, seal kits, packing)
Sensors Shock
AbsorbersSilencersStrainers
Switchs (all types)
Test
EquipmentThreadlock Adhesives
Transducers & Transmitters
Tubing & Shafting (metal,
plastic)Valves (ball, cartridge,
check, directional control, electro-pneumatic, flow control, pilot, pneumatic,
pressure control, proportional, servo,
solenoid)Wear
Rings
Always to be considered are the
properties and characteristics of the fluids handled: water-, petroleum-,
systhetic-, and/or vegetable-based. Must be able to compare performance
and application of each. Must understand selection criteria.
The detrimental effects of
contaminants on hydraulic fluid, components, systems, and performance must
be understood. Must know different types and forms of contaminants
and their sources. Must understand fluid sample analysis to determine
degree and nature of contamination as a step toward improving fluid
cleanliness.
Fluid filtration as an integral
step toward cleanliness in fluids. Important are: filter placement
within a system (suction, pressure, and return lines, plus off-line filtration),
advantages and disadvantages of each type of filter media, filter construction,
and filter ratings and performance. Must understand selection criteria for
best fit.
Three important areas to an understanding of pneumatic systems:
Gas Dynamics - must understand
general gas laws, standard conditions for air, how to run calulations, and
gas behavior during compression and expansion.
Flow Rates - must understand
the flow of incompressible fluids (liquids), the flow of compressed air,
the SCFM concept, and be know how to run calculations.
Valve Pressure Drop - must understand
liquid and air valve coefficients, air valve selection, tables to simplify
calculations, and know how to run calculations.
Different types of noise (airborne, structure-borne, and fluid-borne). Need
an understanding of sound pressure, sound level, decibels, the A scale, and
harmonics. The sources of noise may be pumps, motors, and/or valves.
Must know noise control - controlling noise at the source, source
isolation, increasing the natural frequency of transmitters, and streamlining
and insulating noise sources from their surroundings.
Ballscrews
Bearings (all types)
Belting
Brakes & Clutches
Breathers
Bushings (ball)
Chains
(roller) Collars
Connections (hub & shaft)
Controls (motor)
Conveyors & Components
Couplers & Couplings
Drives (all
types) Drum Motors
Encoders
Ends (rod)
Expansion Chambers
Gears (gear boxes, gear
heads) Gib Liners
Guides (linear
motion) Inverters
Isolation
Mounts Linear Motion
ProductsLinkages & Connecting
Rods Locknuts
Lubrication Systems
Motor Controls
Motorized Pulleys Motors (brushless
DC, electric-all types, gear, induction)
Pulleys
Reducers
(speed) Relief Vents
(pressure/vacuum)
SealsSplines Sprockets
(all types) Starters (solid
state)Switches
Tables (positioning)
Timing Devices
Torque Transmission
Wear Strips
Winches
To prevent additional failures, it is often necessary to understand why something failed. You need to be able to recognize the various types of failures, normal operating stresses, effects of inadequate lubrication, momentary overloads, and fatique loads. Futhermore, attention should be paid to setting up a failure analysis program.
Many decision makers consider predictive maintenance programs too complex and costly. In some cases, this is true. You must consider the phases, from planning initial concepts and developing cost-benefit analysis to carrying the project to maturity. You need to understand how a mature program operates and the methods to ensure they meet realistic criteria.
With the wide variety of servos available, it is tempting to select whatever is familiar. However, that type may not offer the optimum performance or economy. The application information needed to make decisions must be developed. An understanding of ac, dc, and vector servo drive technologies with emphasis on adjustment procedures, manual and auto-tuning, and the economic factors must be in place.
Actuators (linear)
Amplifiers (servo)
Blocks
(terminal) Blowers
Controllers
Dampers (inertia)
Data
Acquisition Distributed Control
Systems Drivers (step
motors)Fans
Slides (components & systems)
Motors (DC brushless, compact
gear, stepper)Measuring Systems
Relays
Sensors (capacitive, fibre optic,
inductive, magnetic, photoelectric, pressure, ultrasonic)
Signal
Conditioning Software (various
and for step motors)
Switches
Must have an understanding of analog electrohydraulic controls and basic control loops (with regard to speed control and load disturbances), ability to select sensors relative to speed, torque, pressure, and flow measurements. Must know control valves with emphasis on proportional and servo-quality proportional valves, and PID control, including control algorithms and proportional, integral, and theoretical derivative control action.
Must understand the functions and advantages of transducers and how to integrate them into systems.
Types of Transducers - pressure,
linear-displacement, rotary, temperature, and other special types.
Application Considerations -
electrical interfacing, measurement range, placement within a system, and
connections.
Evaluation of selection alternatives
by weighing variables to reach an intelligent decision.
Motion control applications vary widely in speed, positioning, coordination,
and other parameters. There is an equally wide choice of control options
on the market, from the simple operator's devices to programmable logic
controllers and industrial computers. You must understand how to match
a controller to an application's performance and economic
constraints.
Pros and Cons of each type of software solutions /applications for consideration. A competitive evaluation of vendors' products and capabilities is part of project assessment and an integral responsibility of the Project Management Executive.
Assessments begin with an evaluation of the type of application, since there are over 100 categories for specifying an MES (Manufacturing Execution System).
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unhappy!
