MTS Material Test System Operation 100-196-370 D be certain.
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Contents 1.0 Preface 5 1.1.0 Before You Begin............................................................................................................................6 1.2.0 Documentation Conventions...........................................................................................................6 2.0 Technical Support 9 2.1.0 How to Get Technical Support......................................................................................................10 2.2.0 Before You Contact MTS.....
5.7.0 Connecting the System Components.............................................................................................40 5.8.0 System Startup...............................................................................................................................41 6.0 Getting Started 43 6.1.0 Overview.......................................................................................................................................44 6.2.0 Define the Test Configuration...............
1.0 Preface Topics: • • Before You Begin.....................................................................................................................................6 Documentation Conventions....................................................................................................................
1.0 Preface 1.1.0 Before You Begin Safety first! Before you use your MTS product or system, read and understand the safety information provided with your system. Improper installation, operation, or maintenance can result in hazardous conditions that can cause severe personal injury or death, or damage to your equipment and specimen. Again, read and understand the safety information provided with your system before you continue.
1.0 Preface Other special text conventions Important: Important notices provide information about your system that is essential to its proper function. While not safety-related, if the important information is ignored, test results may not be reliable, or your system may not operate properly. Note: Notes provide additional information about operating your system or highlight easily overlooked information.
2.0 Technical Support Topics: • • • • How to Get Technical Support...............................................................................................................10 Before You Contact MTS.......................................................................................................................10 If You Contact MTS by Phone...............................................................................................................12 Problem Submittal Form in MTS Manuals.........
2.0 Technical Support 2.1.0 How to Get Technical Support Start with your manuals The manuals supplied by MTS provide most of the information you need to use and maintain your equipment. If your equipment includes software, look for online help and README files that contain additional product information. Technical support methods MTS provides a full range of support services after your system is installed.
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2.0 Technical Support 2.3.0 If You Contact MTS by Phone A Call Center agent registers your call before connecting you with a technical support specialist. The agent asks you for your: • Site number • Name • Company name • Company address • Phone number where you can be reached If your issue has a notification number, please provide that number. A new issue will be assigned a unique notification number.
2.0 Technical Support After you call MTS logs and tracks all calls to ensure that you receive assistance for your problem or request. If you have questions about the status of your problem or have additional information to report, please contact Technical Support again and provide your original notification number. 2.4.
3.0 Introduction Topics: • • • • Manual Overview...................................................................................................................................16 Typical Test System Configuration.........................................................................................................16 System Control Theory..........................................................................................................................22 Interlocks................................
3.0 Introduction 3.1.0 Manual Overview This manual provides operating guidelines, installation guidelines, and safety practices for operation of an MTS Test System. This manuals deals primarily with the hardware components used to configure a typical MTS load frame based materials testing system: the load frame, the grips and fixtures used to secure the specimen during testing, and the MTS Hydraulic Power Unit.
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3.0 Introduction Item Description 2 Hydraulic service manifold 3 Hose connections: • Pressure • Return • Drain 4 Hand set (some models) 5 Actuator speed switch (some models) 6 E-Stop button 7 Hydraulic lift lock controls 8 Grip controls 9 Linear actuator 10 Load cell Additional testing accessories are also available. For information on optional accessories, refer to the individual product manuals.
3.0 Introduction Item Description 1 Environmental Accessories 1A. High temperature furnace 1B. Environmental chamber 1C. Temperature controller 2 Extensometers 3 Alignment accessories 3A. High temperature furnace 3B. Environmental chamber 4 Remote station control 5 Remote E-Stop (optional) 6 Test area guard 7 Grips and bend fixtures 3.2.1.0 Load Frame Test Controller The test controller can be either a FlexTest SE Basic, FlexTest SE Plus, FlexTest GT, or FlexTest 40/60/100/200.
3.0 Introduction 3.2.2.0 Servohydraulic and Mechanical Components The following paragraphs briefly describe the servohydraulic and mechanical components that are typical supplied with the MTS Landmark System. Load frame There are a variety of load frames that can be supplied with the system. The load frame is the mechanical foundation of the test system in which the load cell transducer, specimen fixturing or grips, and hydraulic actuator are mounted.
3.0 Introduction Hydraulic power supply The hydraulic power unit (HPU) provides pressurized hydraulic fluid to the servovalve. An HPU typically includes a reservoir for the hydraulic fluid, a pump to pressurize the hydraulic fluid, a motor to run the pump, a heat exchanger to cool the hydraulic fluid, and sensors to monitor the level, pressure, and temperature of the hydraulic fluid.
3.0 Introduction Table 3: Simple Control diagram Item Description 1 Test command 2 Summing and conditioning 3 Station manager 4 Closed loop 5 Feedback source When reduced to its basic form, a Series 793 test system typically includes these elements. (The command can also be provided by a function generator or MultiPurpose TestWare).
3.0 Introduction 3.4.0 Interlocks The test controller incorporates interlock circuitry that can automatically stop a test when a system problem, specimen failure, or an operator error could result in unwanted or unexpected actuator movement. The test controller interlock circuitry will cause one of two interlocks to occur in response to specific conditions encountered during testing. These interlocks are: • Hydraulic Interlock – stops the program and removes hydraulic pressure from the system.
4.0 Safety Topics: • • Overview................................................................................................................................................26 Safety Practices.....................................................................................................................................
4.0 Safety 4.1.0 Overview 4.1.1.0 Safety Information Overview MTS systems are designed to generate single-axis or multi-axial motions and forces simultaneously in a controlled environment and impart these motions and forces into a specimen that is secured to the system.
4.0 Safety 4.2.0 Safety Practices 4.2.1.0 General Safety Practices If you have system related responsibilities (that is, if you are an operator, service engineer, or maintenance person), you should study this manual carefully before you attempt to perform any test system procedure. You should receive training on this system or a similar system to ensure a thorough knowledge of your equipment and the safety issues that are associated with its use.
4.0 Safety Locate lockout/tagout points Know where the lockout/tagout point is for each of the supply energies associated with your system. This includes the hydraulic, pneumatic, electric, and water supplies (as appropriate) for your system to ensure that the system is isolated from these energies when required. Know facility safe procedures Most facilities have internal procedures and rules regarding safe practices within the facility.
4.0 Safety Ensure Correct Cable Connection If a system cable has been disconnected, ensure that you establish the correct cable-to-connector relationship during reconnection. Incorrect cable connections can result in improper servo loop phasing or an open servo loop condition, either of which can cause unstable or unexpected and potentially dangerous system motions. Verify the correct cable-to-connector relationship by observing the cable and connector labeling and the system wiring schematics.
4.0 Safety the recommended procedure for bleeding a pneumatic or gas-charged device, because it can expose you to the dangers of escaping compressed gas and particulates that are expelled from the chamber or around the seals. Do not assume that cover plates and ports are installed in all the critical locations. Consult MTS when in doubt about the safety or reliability of any system-related procedure or modification that involves devices that contain any type of compressed gas.
4.0 Safety Provide test area guards Use protective guards such as cages, enclosures, and special laboratory layouts when you work with hazardous test specimens (for example, brittle or fragmenting materials or materials that are internally pressurized). Do not exceed the Maximum Supply Pressure For hydraulic systems and components, make sure that hydraulic supply pressure is limited to the maximum pressure defined by the system operating limits. Read and review “System Operating Limits” for the system.
4.0 Safety Customer must evaluate risks due to ejected parts or materials from the test specimens. If the MTS Test Area Enclosure option is not selected by the customer, then for protection against ejected parts or materials from test specimens and to control access to the machinery, the Customer must provide a Test Area Enclosure to protect personnel. Specimen temperature changes During cyclic testing, the specimen temperature can become hot enough to cause burns.
4.0 Safety Contain small leaks Do not use your fingers or hands to stop small leaks in hydraulic or pneumatic hoses. Substantial pressures can build up, especially if the hole is small. These high pressures may cause the oil or gas to penetrate your skin, causing painful and dangerously infected wounds. Turn off the hydraulic supply and allow the hydraulic pressure to dissipate before you remove and replace the hose or any pressurized component.
5.0 Installation Guidelines Topics: • • • • • • • • Installation Guidelines............................................................................................................................36 Facility Preparation................................................................................................................................36 Electrical Power Distribution..................................................................................................................
5.0 Installation Guidelines 5.1.0 Installation Guidelines The MTS Test System is typically installed by qualified MTS field service engineers. This section provides reference information as it applies to a typical system configuration that might help you become more familiar with your system. The difference in test setup and laboratory layouts will influence the final layout of the testing system components. These and other customer specific requirements must be considered prior to system installation. 5.
5.0 Installation Guidelines laboratory personnel, use of an overhead crane, lifting straps or a forklift might be necessary to handle components or fixtures. Heat dissipation To provide adequate heating and air conditioning to the test area for comfortable working conditions and proper operation of the equipment, the heat dissipation of the hydraulic power equipment, electronics console and other equipment must be considered.
5.0 Installation Guidelines addition, it is recommended that the hydraulic power unit be located in a room separate from the test system, if possible, to reduce noise in the test area. Mechanical shock/vibration In testing situations where impact testing is performed or in higher speed fatigue testing, cyclic loads and simple shock pulses can be introduced into the laboratory floor. Adequate isolation is often possible with vibration isolators.
5.0 Installation Guidelines must be provided by the customer to allow maintenance personnel to safely remove all power to the HPU. Wiring must conform to local electrical codes and regulations. 5.4.0 Grounding Requirements Each system has its own internal grounding network, which is common grounded through the green wire in the power cable and must also return to ground, through the conduit of the electrical distribution system.
5.0 Installation Guidelines Due to the high center of gravity of the console, two people are required to roll the console if the floor has obstructions or bumps; use one person on each side of the console to watch for obstructions. Move the unit with the front panel controls away from the direction of travel to minimize the damage that could occur if the console tipped over. Routing cables The cable exit from the console is at the rear, through a slot below the rear door.
5.0 Installation Guidelines supplied with the system, some of these connections might not apply. If provided, refer to the system assembly and/or hydraulic distribution drawings (located on the system Reference Manual CD) for additional information regarding point-to-point hydraulic connections. Cable Connections MTS Systems Corporation categorizes cables as either being console cables or system cables.
5.0 Installation Guidelines Actuators After checking the electrical and hydraulic power unit connections, the actuator position control electronics (the Set Point control on the selected controller) should be checked for signal polarity and control. This is accomplished by performing the following steps: 1. Clear the area around the piston rod of obstructions. 2. Select the desired control mode (typically load). 3. Clear any active interlocks. 4.
6.0 Getting Started Topics: • • • • • Overview................................................................................................................................................44 Define the Test Configuration................................................................................................................44 Define the Test Parameters...................................................................................................................46 Select Test Setup Methods.....
6.0 Getting Started 6.1.0 Overview Before setting up or operating the test system, the hardware component configuration must be defined, control settings (or test parameters) should be calculated, and test setup decisions must be made. This section describes some of the factors to consider when completing these pre-operation procedures. Define the test configuration Identifies factors to consider when selecting the hardware for a test.
6.0 Getting Started For balanced system operation, the load frame crosshead should be positioned so that the actuator piston rod will be at approximately midstroke when the specimen is installed into its upper and lower grips/fixtures. For detailed information on crosshead operation and specimen mounting considerations, refer to the load unit product manual. Refer to the individual grip and fixture manuals for more information on installing these components on the load frame. 6.2.2.
6.0 Getting Started than one signal is selected as the input, the underpeak detector will not trigger an interlock unless all of the selected signals are below the specified level. 6.3.0 Define the Test Parameters There are several test parameters that must be defined before beginning test setup and operation.
6.0 Getting Started Table 5: Effects of Span and Setpoint on Program Signal Item Description 1 Full-scale operating range 2 Testing range 3 Span affects program amplitude 4 Setpoint affects program mean level 5 Mean level offset Important: In load control, the actuator rod will move with a slight Setpoint control adjustment and will not stop until the Setpoint control is returned to 0.
6.0 Getting Started Table 6: Error detection level Item Description 1 Program command 2 Feedback 3 DC Error 4 Time lag The error detector can be preset to detect an excessive DC error. The level of acceptable DC error depends directly on the accuracy requirements of each testing situation. In static and low-frequency tests, error detectors are typically adjusted for levels that would stop the test when a specimen fractures or excessive deformation occurs.
6.0 Getting Started through the system interlock. Likewise, if the feedback falls below the preset lower limit detect level, the limit detector will (if enabled during test setup) stop the test through the system interlock.
6.0 Getting Started Determining limits from known test forces or displacements If the maximum and minimum test forces or displacements are known, the limit detector levels can be determined and adjusted to the required levels before specimen installation. The test configuration, test program, and fixturing are all factors to consider when determining the limit detector levels.
6.0 Getting Started Table 8: Underpeak Detector Levels Item Description 1 Full-scale operating range 2 Maximum underpeak detect level 3 Maximum underpeak detected 4 Minimum underpeak detect level 5 Minimum underpeak detected The underpeak detector is typically set to stop a test before specimen failure. This minimizes the chance of equipment damage that may result if the specimen fractures.
6.0 Getting Started • The input to the underpeak detector is the transducer feedback signal from a load cell with a full-scale operating range of ±25 kN • There is zero load after the specimen is installed • Specimen failure is defined as a ±20% drop in load (in respect to a +20 kN initial force at the programmed maximum and minimum displacements) With these conditions, the following underpeak detector levels can be set.
6.0 Getting Started Table 9: Gain adjustment Item Description 1 Response time 2 Program 3 Transducer feedback Increasing the gain decreases the stability margin of the system, increases the frequency of oscillation, and decreases response time. The following figure shows the effect on the transducer feedback of increasing the gain adjustment.
6.0 Getting Started Item Description 3 Program 4 Transducer feedback If the gain is set too high, unstable system operation can result. This instability may cause specimen damage. Consequently, gain should be set as high as possible while maintaining stable system operation. Rate (D) The rate adjustment improves the servo control loop dynamic stability by reducing the overshoot at higher proportional gain settings.
6.0 Getting Started Summary Servo loop adjustments are experimental and the operator should become familiar with the effects of these adjustments while using dummy specimens during both dynamic and static system operation. Because each adjustment can have some effect on the others, adjustments to the servo loop should be made using several iterations. This iteration sequence is provided in the operation section of this manual. 6.5.
7.0 Operation Topics: • • • • • • • • Operation Overview...............................................................................................................................58 Initial Setup............................................................................................................................................58 Set Detector Levels................................................................................................................................
7.0 Operation 7.1.0 Operation Overview This section contains a typical operating sequence that will lead you through local test setup and operation. Detailed information can be found in the Series 793 Overview manual and various product manuals. Before starting the operating procedure The information in Getting Started, should be reviewed and fully understood before beginning the operating procedure described in this section.
7.0 Operation • Determine the position of the load frame crosshead. • Calculate the upper and lower limit detection levels to be used during specimen installation. • Calculate the upper and lower limit detection levels to be used during the test. • Determine which signals should be monitored during the test. • Select the external readout/data acquisition devices to be used during the test. • Select the appropriate data acquisition transducers for the test (typically strain gages.) 2.
7.0 Operation 7.4.0 Adjust Displacement Servo Loop (optional) Note: If the test is to be run in displacement control, then displacement control loop should be tuned for optimal performance. 1. 2. 3. 4. Select displacement control. Clear active interlocks. Apply hydraulic pressure. Adjust the displacement (P) and Rate (D) controls. Note: The following steps are provided as a guide to the servo loop adjustments.
7.0 Operation Warning: After you turn off system hydraulics, do not come near the load frame for at least 30 minutes – actuator motion is still possible. Unexpected actuator response can result in personal injury or equipment damage. Actuator motion is still possible after you turn off system hydraulics. Unexpected actuator response can result in personal injury or equipment damage.
7.0 Operation Caution: Oil spillage can create an environmental concern and a slippery surface. Slippery surfaces can cause you to fall and incur personal injury. When changing hydraulic grips, make sure you cap or plug the hydraulic hoses when they are removed to prevent oil spillage. Promptly clean up any oil that might have spilled when hoses were removed. Warning: The crosshead is very heavy. A dropping crosshead can crush hands, damage grips, and smash specimens.
7.0 Operation Note: If possible, install a dummy specimen at this time. Use of a dummy specimen will help avoid potential damage to the test specimen when establishing the servo loop response and stability. The dummy specimen should be a representative model of the test specimen. 3. Install the specimen. Specimen installation varies according to the type of grip being used. Each type of grip requires the specimen or specimen fixture to fit properly into the grip.
7.0 Operation Caution: Oil spillage can create an environmental concern and slippery surface that can cause personal injury. When changing hydraulic grips, make sure you cap or plug the hydraulic hoses when removed to prevent oil spillage. Promptly clean up any oil that might have spilled when hoses were removed. Caution: The crosshead is very heavy. A dropping crosshead can crush hands, damage grips, and smash specimens. Be careful when working in a crush zone.
7.0 Operation Note: If possible, install a dummy specimen at this time. Use of a dummy specimen will help avoid potential damage to the test specimen when establishing the servo loop response and stability. The dummy specimen should be a representative model of the test specimen. Warning: Specimen installation is a hazardous procedure because of the proximity of the operator to force train components with hydraulic pressure applied.
7.0 Operation Note: The following steps are provided as a guide to the servo loop adjustments. Adjustment of these controls will vary depending on the test specimen and the components of the test system (for example, test fixtures, type of feedback, hydraulic components, etc). As operator experience is gained, the steps can be modified to achieve the desired response. 1. Set the Span control to zero. 2. Set up the oscilloscope to monitor the program command and load signal.
7.0 Operation 7.7.0 Set Up the Program, Detectors, Counter, and Data Acquisition Following is a brief procedure to set up the program command. Detailed information on computer-controlled set up can be found in the Series 793 Overview manual. Caution: The load and displacement signals will cut off (clip) a program signal that exceeds 100% of the full-scale operating range. Clipping a program signal could invalidate the test results.
7.0 Operation 9. If a dummy specimen was installed (as recommended in the specimen Installation section, remove dummy specimen and install test specimen. 10. If desired, set up the Counter. MPT provides several counters. Run time counter: The Run Time counter displays the elapsed time of the current test since the last time it was reset. Channel counters: Channel Counters display a cumulative count of segments or cycles that have been applied to a specific channel since the start of the test.
8.0 Routine Maintenance Topics: • Maintenance Overview..........................................................................................................................
8.0 Routine Maintenance 8.1.0 Maintenance Overview Caution: High pressure fluids can be present in the test system. High-pressure hydraulic fluid can cause cuts and burns. Ensure that you establish and follow standard lock out/tag out safety procedures and the test system is hydraulically isolated before you perform routine maintenance procedures on the test system.
8.0 Routine Maintenance As a guideline, for a test system that operates eight hours per day, one week will equal 40 hours, and one month will equal 160 hours. For a test system that operates up to 24 hours per day, one week will equal 160 hours and one month will equal 720 hours. When to perform visual checks Routine maintenance procedures that are scheduled on a daily or weekly basis usually involve visual checks only, and should not interfere with the operation of your test system.
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9.0 Decommission Topics: • Decommission Test System...................................................................................................................
9.0 Decommission 9.1.0 Decommission Test System The decommissioning process is performed when the system is going to be moved or taken out of service. Disassembly is required when performing either of these tasks. 1. Remove specimen and fixtures. Large grips should be removed if the load frame is going to be tipped over. 2. Move the actuator piston rod down to its lowest position, fully into that cushion. 3.
9.0 Decommission Warning: Warning: Residual hydraulic pressure can produce a high pressure spray. This pressurized hydraulic spray can cut you or the hydraulic fluid could be forced into your skin. Do not start this procedure unless the system has been isolated from hydraulic pressure for at least 20 minutes. Always be cautious when you loosen any hydraulic connection or remove bolts or screws from any hydraulic component.
9.0 Decommission Caution: Warning: Electrical components and parts can contain hazardous chemicals and compounds. Improper disposal of hazardous chemicals and compounds can cause injury and death to people, animals, and plants. In addition, it can cause contamination of the soil, air, and water. Always refer to local codes that govern the disposal of potentially hazardous materials and follow these codes for the proper handling and disposal of these materials.
100-196-370 D
