Category: Instrumentation

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 Dual-Frequency Laser Interferometer: Principles, Usage, Maintenance, Repair, and Brands Overvie

I. Principles of Dual-Frequency Laser Interferometer

The dual-frequency laser interferometer, an advanced measurement instrument based on heterodyne interference principles, evolves from the single-frequency laser interferometer. It utilizes two laser beams of different frequencies for interference measurement, achieving high-precision measurement of various physical quantities such as displacement, length, and angle. This instrument finds wide application in precision machining, metrological inspection, and scientific research, serving as a crucial tool for enhancing equipment accuracy and detection efficiency.

Working Principles:

  • Based on the Zeeman splitting effect and frequency pulling effect.
  • A magnetic field of approximately 0.03 Tesla is applied to a He-Ne laser, generating left- and right-handed circularly polarized light with two different frequencies (f1 and f2).
  • After processing through a series of optical elements, these beams are split into reference and measurement beams.
  • When the movable mirror shifts, the frequency of the measurement beam changes (f2 ± Δf) due to the Doppler effect, while the reference beam’s frequency remains constant.
  • The two beams interfere on a photodetector, producing an electrical signal containing the frequency difference Δf. By counting the changes in frequency difference, the displacement of the movable mirror can be calculated.

Key Components:

  • Laser Source: Employs a laser, such as a He-Ne laser or semiconductor laser, to generate two laser beams with different frequencies.
  • Optical Beam Splitting: The laser beam is divided into two beams by a beam splitter, one serving as the reference beam and the other as the measurement beam.
  • Optical Path Design: The reference beam follows a fixed path, while the measurement beam traverses a variable path. The two beams recombine in the interferometer, producing interference fringes.
  • Interference Fringes: The movement of interference fringes reflects changes in the length of the measurement path. Precise calculations of the displacement or length changes of the measured object can be derived by analyzing these fringes.
  • Signal Processing: The interference fringe signal is converted into an electrical signal by a photodetector and processed to obtain measurement results.

II. Usage Instructions

  1. System Connection: Connect the laptop, laser interferometer, environmental compensation unit, printer, etc., via communication cables and power them on.
  2. Laser Warm-up: Turn on the laser interferometer and allow it to warm up for about 15-20 minutes. Proceed with measurements once the laser is stable (indicator light turns green).
  3. Software Initialization: Start the measurement software on the laptop and enter the corresponding measurement subroutine.
  4. Optical Mirror Installation: Secure the laser interferometer, reflectors, beam splitters, and other optical components on the measurement tripod and machine tool in appropriate positions, and adjust for alignment.
  5. Target Value Setting: Set target values according to measurement requirements and program the CNC measurement procedure.
  6. Data Collection: Initiate the data collection program for automatic or manual data acquisition and monitor the measurement data.

III. Common Faults and Repair Methods

  1. Laser Fault:
    • Symptom: Laser does not emit light or has insufficient intensity.
    • Repair: Check the laser power supply and connection cables, ensuring proper power supply. Replace the laser if necessary.
  2. Optical Path Deviation:
    • Symptom: Interference fringes are unclear or disappear.
    • Repair: Adjust the positions of the beam splitter and reflector to ensure parallel optical paths and accurate beam convergence points.
  3. Photodetector Fault:
    • Symptom: Signal is unstable or there is no signal output.
    • Repair: Check the detector’s power supply and connection cables, clean the detector surface to ensure normal operation.
  4. Environmental Interference:
    • Symptom: Measurement results are highly variable or inaccurate.
    • Repair: Isolate the instrument from environmental vibrations and temperature changes, ensuring a stable working environment.
  5. Signal Processor Fault:
    • Symptom: Data collection is unstable or analysis results are erroneous.
    • Repair: Check signal processor connections and software settings, reinstall or update software if necessary.

IV. Precautions and Maintenance

  • Environmental Requirements: Place the instrument in a dry, clean, and vibration-free environment, avoiding the impact of moisture and dust on optical components.
  • Handling and Storage: Hold the base when moving the instrument to prevent guide rail deformation; store optical components in a clean and dry container when not in use.
  • Cleaning and Lubrication: Avoid wiping mirrors and beam splitters unless necessary, using scientific methods for cleaning; regularly lubricate moving parts to maintain good working condition.
  • Usage Norms: Avoid forced rotation, hard pulling, and other improper operations; apply appropriate force to each adjustment component.

V. Brands and Models of Dual-Frequency Laser Interferometers Repaired by Longi Electromechanical Company

  1. Renishaw
    • XL-80: High-precision laser interferometer system
    • HS20: Dual-frequency laser interferometer for large-range position measurement
  2. Keysight Technologies (formerly Agilent Technologies)
    • 5519A/B: Dual-frequency laser interferometer for high-precision positioning and measurement
    • 5530: Laser interferometer system supporting various measurement applications
  3. Zygo Corporation
    • ZMI 4000 Series: Dual-frequency laser interferometer for high-precision position and speed measurement (ZMI 4500, ZMI 4100)
    • ZMI 2000 Series: High-performance dual-frequency laser interferometer (ZMI 2400, ZMI 2002)
  4. SIOS Messtechnik
    • SP 2000 Series: Dual-frequency laser interferometer system for precise length and angle measurement (SP 2000, SP 2000 TR)
    • SP 5000 Series: High-resolution dual-frequency laser interferometer (SP 5000 NG, SP 5000 TR)
  5. Hamar Laser Instruments
    • L-730 Series: Dual-frequency laser interferometer for machine calibration and alignment (L-730, L-740)
    • L-750 Series: High-precision dual-frequency laser interferometer (L-750)
  6. API (Automated Precision Inc.)
    • XD Series: High-precision laser interferometer system (XD6, XD8)
  7. Renishaw/Anorad (Collaborative Brand)
    • RLE Series: High-performance laser interferometer (RLE10, RLE20)
  8. Mahr Metrology
    • MarForm MFU Series: High-precision laser interferometer for shape measurement and surface contour measurement (MFU 100, MFU 200)
  9. Mitutoyo
    • Laser 20: Dual-frequency laser interferometer for high-precision position measurement
    • Laser 30: High-performance dual-frequency laser interferometer
  10. Status Pro
    • EZ-EL Series: High-precision laser interferometer system (EZ-EL-A, EZ-EL-B)
  11. Tokyo Seimitsu
    • LV-50
  12. Marposs
    • BLU Series:
      • BLU LT: For length and displacement measurement
      • BLU LI: For straightness and angle measurement

Longi Electromechanical Company specializes in the repair of dual-frequency laser interferometers, with nearly 30 years of experience. We can quickly repair various instruments and also offer the recycling and sale of used dual-frequency laser interferometers. Welcome to consult us.

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Ammonia-Nitrogen Analyzer: Principles, Usage, Maintenance, and Brands Overview

I. Principles of Ammonia-Nitrogen Analyzer

The ammonia-nitrogen analyzer is an instrument specifically designed to detect ammonia-nitrogen content in water samples. It is widely used in environmental monitoring, drinking water treatment, and wastewater treatment. The analyzer’s working principle is mainly based on chemical reactions and optical measurements. Common measurement methods include the Nessler’s reagent spectrophotometric method and the salicylic acid spectrophotometric method. Taking the Nessler’s reagent method as an example, the principle is that free ammonia or ammonium ions in the water sample react with Nessler’s reagent (an alkaline solution of potassium iodide and mercuric iodide) to form a pale reddish-brown complex. The absorbance of this complex is proportional to the ammonia-nitrogen content. By measuring the absorbance at a specific wavelength (such as 420 nm), the ammonia-nitrogen concentration in the water sample can be calculated.

II. Usage Instructions

Preparation:

  • Clean the cuvettes and measuring cups to ensure no residues or impurities.
  • Connect the instrument to a power source, turn it on, and preheat for at least half an hour.
  • Set detection parameters such as detection range and sample volume according to the instrument manual.

Sample Processing:

  • Take a certain amount of water sample (usually 10 mL), add appropriate reagents (such as N-NH3-1 and N-NH3-2 reagents), shake well, and let stand for a certain time (such as 10 minutes).
  • If the water sample contains interfering substances such as suspended solids, residual chlorine, calcium, and magnesium ions, appropriate pretreatment is required to eliminate the interference.

Measurement:

  • Add the processed water sample to the cuvette, place it in the instrument’s measurement seat, and cover with a light-shielding cover.
  • Start the instrument for measurement and wait for a certain time (usually a few minutes to tens of minutes) until the display stabilizes.
  • Read and record the ammonia-nitrogen concentration value.

Cleaning and Maintenance:

  • After measurement, clean the cuvettes and reagent bottles, and store them properly.
  • Regularly calibrate and maintain the instrument to ensure stable performance.

III. Common Faults and Repair Methods

  • Instrument Startup Abnormality: Causes include power failure, internal circuit failure, or software failure. Repair methods include checking the power supply, replacing damaged power sources, inspecting internal circuits, repairing faulty circuits, and attempting to restart the instrument or update the software.
  • Deviation in Measurement Results: Causes include reagent issues, instrument calibration problems, or improper operation. Repair methods include checking if the reagents are expired or contaminated, replacing them with new ones, performing instrument calibration, and ensuring accurate and reliable operation, as well as checking the correctness of the operation process and correcting improper operations.
  • Communication Failure: Causes include faulty communication cables, loose interfaces, or software compatibility issues. Repair methods include checking the integrity of communication cables, replacing damaged ones, inspecting interface connections, reconnecting them, and checking software compatibility, updating the software, or replacing it with more compatible software.
  • Mechanical Failure: Causes include worn pump bodies and loose pipelines. Repair methods include inspecting the wear condition of mechanical parts, replacing severely worn components, checking pipeline connections, and re-securing them, as well as performing regular instrument maintenance.
  • Display Panel Abnormality: Causes include a damaged display screen, poor line contact, or power failure. Repair methods include checking if the display screen is damaged and replacing it, inspecting line connections and reconnecting them, and checking the power supply and replacing damaged power sources.

IV. Summary of Brands and Models Repaired by Rongji Electromechanical Company

  • Hach:
    • NA8000
    • DR3900: Benchtop Spectrophotometer supporting ammonia-nitrogen determination
    • DR6000: High-precision Benchtop UV-Vis Spectrophotometer supporting ammonia-nitrogen determination
    • Nitratax plus sc: Online Ammonia-Nitrogen Analyzer
    • HQD Series, HQ40D, HQ30D
  • YSI (Xylem Inc.):
    • ProDSS: Multi-parameter Water Quality Analyzer with ammonia-nitrogen determination module
    • IQ Sensor Net Series: AmmoLyt Plus: Online Ammonia-Nitrogen Sensor, VARiON Plus: Online Multi-parameter Ion-selective Electrode System
  • Thermo Fisher Scientific:
    • Orion Star A Series: Star A329: Benchtop Multi-parameter Analyzer supporting ammonia-nitrogen determination, Star A326: Portable Multi-parameter Analyzer supporting ammonia-nitrogen determination
    • Orion AQUAfast AQ4000: Multi-parameter Photometer supporting ammonia-nitrogen determination
  • Hanna Instruments:
    • HI83399: Multi-parameter Photometer supporting ammonia-nitrogen determination
    • HI96715: Portable Ammonia-Nitrogen Photometer
    • HI93532: Benchtop Ammonia-Nitrogen Analyzer
  • Horiba:
    • LAQUAtwin NH4-11: Portable Ammonia-Nitrogen Analyzer
  • Lovibond:
    • MD 600: Multi-parameter Portable Water Quality Analyzer supporting ammonia-nitrogen determination
    • SpectroDirect: Spectrophotometer supporting ammonia-nitrogen determination
  • LaMotte:
    • Smart 3 Colorimeter: Portable Multi-parameter Water Quality Analyzer supporting ammonia-nitrogen determination
    • Nitrate Test Kit: Ammonia-Nitrogen Test Kit
  • Palintest:
    • Photometer 7500: Benchtop Multi-parameter Analyzer supporting ammonia-nitrogen determination
    • AquaPal Series: AquaPal Photometer: Portable Multi-parameter Water Quality Analyzer supporting ammonia-nitrogen determination, Macro 900 Series: Multi-parameter Portable Water Quality Analyzer supporting ammonia-nitrogen determination
  • Mettler Toledo:
    • SevenExcellence Series: S470: Benchtop Multi-parameter Analyzer supporting ammonia-nitrogen determination, S475: Benchtop Multi-parameter Analyzer supporting ammonia-nitrogen determination
  • Aquaread:
    • AP Series: AP-7000: Multi-parameter Water Quality Probe supporting ammonia-nitrogen determination, AP-8000: Multi-parameter Water Quality Probe supporting ammonia-nitrogen determination
  • Shimadzu:
    • UV-Vis Spectrophotometer Series: UV-1900i: UV-Vis Spectrophotometer supporting multiple water quality parameters determination, including ammonia-nitrogen, UV-2600i: UV-Vis Spectrophotometer suitable for high-precision water quality analysis, including ammonia-nitrogen, UV-3600i Plus: High-performance UV-Vis Spectrophotometer suitable for ammonia-nitrogen determination in complex water samples
    • TOC-L Analyzer Series: TOC-LCPH/CPN: Total Organic Carbon Analyzer, which can be used for ammonia-nitrogen determination with appropriate accessories, TOC-LCSH/CSN: High-sensitivity Total Organic Carbon Analyzer supporting ammonia-nitrogen determination
    • Ion Chromatography Series: ICPE-9800 Series: Inductively Coupled Plasma Emission Spectrometer suitable for trace ammonia-nitrogen determination, ICPE-9000 Series: Multi-function Ion Chromatograph that can be used for ammonia-nitrogen determination
    • Automatic Analyzer Series: AA-7000 Series: Atomic Absorption Spectrometer, which can be used for ammonia-nitrogen determination with appropriate accessories
    • Nexis GC-2030 Gas Chromatograph: Can be used for ammonia-nitrogen determination with appropriate detectors and columns.

Rongji Electromechanical Company has nearly 30 years of experience in repairing ammonia-oxygen analyzers and can quickly repair various instruments. Additionally, the company回收 (recycles) and sells various used ammonia-oxygen analyzers. For more information, please contact us.

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 Comprehensive Guide to Water Quality Analyzers: Principles, Usage, Faults, and Brands

Introduction

The water quality analyzer, also known as the water quality detector, is a precision instrument specifically designed to detect and analyze various physical, chemical, and biological parameters in water bodies. It finds wide application in drinking water monitoring, wastewater treatment, environmental protection, and industrial process control, serving as a crucial tool to ensure water quality safety and enhance environmental protection standards.

1. Functional Principles

The functional principles of water quality analyzers are primarily based on various physical, chemical, and biological sensing technologies, assessing water quality by measuring specific parameters in water bodies. Its working principles may include:

  • Ion-Selective Electrode Measurement: Utilizes electrodes to selectively respond to specific ions in water, determining ion concentrations through the measurement of potential differences or currents generated by the electrodes. Commonly used for measuring pH, fluoride, sodium, potassium, calcium, and magnesium ion concentrations.
  • Photoelectric Technology: Employs photoelectric sensors to measure optical properties in water, such as turbidity and chroma. Inferences about certain physical or chemical properties of water can be made based on the intensity or changes in light signals received by the photoelectric sensors.
  • Computer Analysis Technology: Combines photoelectric technology with other sensing technologies, utilizing computers to process and analyze measurement data, deriving various parameters of water quality. This method enables rapid and accurate water quality monitoring and analysis.

2. Usage Method

The usage method of a water quality analyzer typically includes the following steps:

  1. Prepare Sample: According to experimental needs, prepare the water sample to be tested, ensuring the purity and quality of the sample.
  2. Establish Experimental System: Set appropriate experimental conditions and parameters based on experimental requirements.
  3. Instrument Adjustment: Adjust and optimize the water quality analyzer to ensure it is in optimal working condition.
  4. Add Sample: Introduce the water sample to be tested into the instrument, ensuring good contact between the sample and the instrument.
  5. Conduct Experiment: Start the instrument, initiate the experimental process, record experimental data, and observe results.
  6. Data Analysis: Process and analyze experimental data to derive various parameters and assessment results of water quality.
  7. Clean Equipment: Thoroughly clean the water quality analyzer after the experiment to avoid cross-contamination.

3. Common Faults and Repair Methods

Water quality analyzers may encounter certain faults during usage. Below are some common faults and their repair methods:

  • No Display upon Startup:
    • Fault Causes: Power not connected, switch issue, LCD or wiring issue.
    • Repair Methods: Check if the power cord is connected; replace the switch; confirm the normality of the LCD and wiring, and replace if necessary.
  • Poor Data Repeatability:
    • Fault Causes: Insufficient instrument warm-up time, unstable external voltage, poor instrument grounding.
    • Repair Methods: Allow the instrument to warm up sufficiently after startup (e.g., 30 minutes); improve the instrument’s working environment to ensure stable external voltage; check and improve the instrument’s grounding state.
  • Measurement Values Too High or Too Low:
    • Fault Causes: Contamination of the measurement system, electrical drift.
    • Repair Methods: Flush the instrument’s measurement flow path with high-purity water to remove contamination; perform curve calibration on the instrument to eliminate electrical drift.
  • Blocked Drainage:
    • Fault Causes: Blocked drainage connector, folded drainage tube, solenoid valve issue.
    • Repair Methods: Flush the drainage connector and measurement flow path with high-purity water; check for folds in the drainage tube and adjust; check or replace the solenoid valve.
  • No Sample Intake:
    • Fault Causes: Insufficient water sample pressure, faulty or blocked channel valve, filter blockage.
    • Repair Methods: Adjust the sample intake pressure; replace the solenoid or channel valve; replace the filter to clear the blockage.
  • Standard Solution or Reagent Not Added:
    • Fault Causes: Lack of standard solution or reagent, air resistance in the tubing, faulty standard solution or reagent valve.
    • Repair Methods: Add standard solution and reagent; vent the tubing to eliminate air resistance; replace the standard solution or reagent valve.

Note: The above repair methods are for reference only. Specific repair operations should be carried out according to the instrument manual and actual situation. During repairs, ensure safe operation to avoid damaging the instrument or causing personal injury. If faults cannot be resolved independently, it is recommended to contact professional repair personnel from Rongji Electromechanical for assistance.

4. Brands and Models of Water Quality Analyzers Repaired by Longi Electromechanical

  1. Hach
    • DR3900: Benchtop Spectrophotometer for multi-parameter water quality analysis
    • DR6000: High-precision Benchtop UV-Vis Spectrophotometer
    • SL1000: Portable Multi-parameter Analyzer
    • HQD Series: Professional portable and benchtop multi-parameter analyzers, e.g., HQ40D, HQ30D
    • MS5: Portable Water Quality Multi-parameter Probe
  2. YSI (Xylem Inc.)
    • ProDSS: Multi-parameter Water Quality Analyzer for field and laboratory use
    • EXO2: Multi-parameter Water Quality Probe System
    • ProQuatro: Portable Multi-parameter Water Quality Analyzer
    • Pro2030: Dissolved Oxygen and Temperature Analyzer
    • ProPlus: Multi-parameter Portable Analyzer
  3. Horiba
    • U-50 Series: Multi-parameter Water Quality Analyzers, U-52, U-53, U-54, U-55, U-52G
    • LAQUA Series: Laboratory Multi-parameter Analyzers, LAQUAact, LAQUAtwin
  4. Thermo Fisher Scientific
    • Orion Versa Star Series: High-end Multi-parameter Analyzers, Versa Star Pro
    • Orion Star A Series: Portable and Benchtop Water Quality Analyzers, Star A329
    • Orion AquaMate 8000: Spectrophotometer
  5. Xylem Analytics
    • WTW MultiLine Series: Multi-parameter Water Quality Analyzers, MultiLine 3510 IDS, MultiLine 3420 IDS
    • WTW InoLab Series: Laboratory Multi-parameter Analyzers, InoLab Multi 9310 IDS, InoLab Multi 9620 IDS
  6. Hanna Instruments
    • HI9829: Portable Multi-parameter Water Quality Analyzer
    • HI83399: Multi-parameter Spectrophotometer
    • HI5522: Laboratory Multi-parameter pH/ISE/EC/DO Meter
  7. Lovibond
    • SpectroDirect: Spectrophotometer
    • MD 600: Portable Multi-parameter Water Quality Analyzer
    • AquaLX: Water Quality Spectrophotometer
  8. Mettler Toledo
    • SevenExcellence Series: High-end Multi-parameter Water Quality Analyzers, S475, S470, S470-Kit
    • Seven2Go Series: Portable Multi-parameter Analyzers, S2, S3
  9. LaMotte
    • Smart 3 Colorimeter: Portable Multi-parameter Water Quality Analyzer
    • TRACER Series: Multi-parameter Probes, TRACER Pocket Tester
    • 2020we/Turbiquant Series: Portable Turbidity Meters
  10. Palintest
    • Photometer 7500: Benchtop Multi-parameter Analyzer
    • AquaPal Series: Portable Water Quality Analyzers, AquaPal Photometer, AquaPal Bluetooth
    • Macro 900 Series: Portable Multi-parameter Water Quality Analyzers

Longi Electromechanical has nearly 30 years of experience in repairing water quality analyzers (water quality detectors, online water quality analyzers), enabling quick and effective repairs for various instruments. Additionally, we recycle and sell various used water quality analyzers. Welcome to consult.

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Comprehensive Guide to Mass Spectrometers: Principles, Usage, Maintenance, and Brands Serviced

I. Functional Principle of Mass Spectrometer

The mass spectrometer, a highly precise scientific instrument, is primarily used to determine the composition and structure of samples. Its operating principle encompasses the following steps:

  1. Sample Ionization: Sample molecules are ionized into positively or negatively charged ions in the ion source.
  2. Mass Separation: The generated ions are accelerated and transmitted to the mass analyzer, where they are separated based on their mass-to-charge ratio (m/z).
  3. Detection and Recording: The separated ions enter the detector, producing signals that are recorded to form a mass spectrum.
  4. Data Analysis: By analyzing the mass spectrum, information such as the composition, structure, and relative abundance of the sample can be determined.

The core components of a mass spectrometer include the ion source, mass analyzer, and detector, all housed within a vacuum system to ensure analytical accuracy.

II. Usage Method of Mass Spectrometer

Usage methods may vary by model and manufacturer, but generally include the following steps:

Preparation:

  • Safety check: Ensure laboratory safety and use personal protective equipment.
  • Sample preparation: Dissolve the sample in an appropriate solvent and clean it to remove impurities.
  • Select the ion source and adjust ionization parameters.
  • Choose the analysis mode and adjust mass spectrometer parameters.

Startup:

  • Turn on the gas supply and mechanical pump, and after achieving the required vacuum, turn on the molecular turbo pump.
  • Perform calibration to ensure optimal mass spectrometer performance.

Analysis:

  • Start the mass spectrometer, observe the mass spectrum, and record corresponding peaks.
  • Analyze the position, intensity, and shape of peaks for mass analysis.
  • Identify compounds in the sample.

Shutdown:

  • Stop the mass spectrometer operation.
  • Flush the system to prevent cross-contamination.
  • Turn off the mass spectrometer and disconnect the power supply.

III. Common Faults and Repair Methods

Common faults and their repair methods include:

  1. Unstable Power Supply:
    • Fault manifestation: Voltage fluctuations, unstable current supply, or sudden power outages and restarts.
    • Repair method: Check power lines and modules, ensure proper grounding, and replace damaged power components.
  2. Aging or Damage of Power Modules:
    • Fault manifestation: Decreased power output performance, insufficient energy for the ion source.
    • Repair method: Replace aged power modules and ensure normal operation of high-voltage components.
  3. Poor Grounding or Contact Issues with Power Lines:
    • Fault manifestation: Increased power noise, interference with signal acquisition, resulting in false peaks or abnormal peak intensities.
    • Repair method: Check grounding and power line connections, ensure good contact, and reduce power noise.
  4. Failure of Power Cooling System:
    • Fault manifestation: Overheating of power supply, leading to drifting output parameters and shortened lifespan.
    • Repair method: Check the cooling system, ensure proper heat dissipation, and replace cooling fans or radiators if necessary.
  5. Failure of Mechanical and Molecular Turbo Pumps:
    • Fault manifestation: Insufficient vacuum, affecting mass spectrometry accuracy.
    • Repair method: Regularly clean and replace mechanical pump oil, check the status of molecular turbo pumps, and repair or replace as needed.
  6. Contamination or Damage of Ion Source:
    • Fault manifestation: Reduced ionization efficiency, poor mass spectrum peak shapes.
    • Repair method: Regularly clean the ion source chamber and sampling cone, and replace damaged ion source components.

IV. Precautions

When using a mass spectrometer, follow laboratory safety regulations and use personal protective equipment. Adjust analysis parameters based on sample properties and mass spectrometer model for optimal results. Regularly perform performance verification and maintenance to ensure long-term efficient operation of the mass spectrometer.

V. Brands and Models of Mass Spectrometers Serviced by Longi Electromechanical

  1. Thermo Fisher Scientific:
    • Orbitrap Series: Orbitrap Exploris 480, Orbitrap Eclipse, Orbitrap Elite, Orbitrap Fusion Lumos
    • Q Exactive Series: Q Exactive, Q Exactive HF, Q Exactive HF-X, Q Exactive Plus
    • TSQ Series: TSQ Altis, TSQ Quantis, TSQ Endura
    • LTQ Series: LTQ Orbitrap XL, LTQ XL
  2. Agilent Technologies:
    • 6500 Series: 6530 Q-TOF, 6546 Q-TOF, 6550 iFunnel Q-TOF, 6560 Ion Mobility Q-TOF
    • 6100 Series: 6130 Quadrupole LC/MS, 6140 Quadrupole LC/MS
    • 7000 Series: 7010 Triple Quadrupole GC/MS, 7000D Triple Quadrupole GC/MS
    • 7700 Series: 7700x ICP-MS
  3. Waters Corporation:
    • Xevo Series: Xevo G2-XS QTof, Xevo TQ-S, Xevo TQ-XS
    • Synapt Series: Synapt G2-Si, Synapt XS, Vion IMS QTof, ACQUITY RDa
  4. Bruker:
    • timsTOF Series: timsTOF Pro, timsTOF fleX
    • MALDI-TOF Series: ultrafleXtreme, autoflex maX
    • ESI-QTOF Series: Impact II, maXis II, scimaX
  5. Sciex (AB Sciex):
    • TripleTOF Series: TripleTOF 6600, TripleTOF 5600+
    • QTRAP Series: QTRAP 6500+, QTRAP 5500, QTRAP 4500
    • Triple Quad Series: Triple Quad 7500, Triple Quad 6500+, Triple Quad 5500
  6. PerkinElmer:
    • Flexar Series: Flexar SQ 300 MS, Flexar TOF MS
    • Clarus Series: Clarus SQ 8 GC/MS
  7. Shimadzu:
    • LCMS Series: LCMS-8045, LCMS-8050, LCMS-8060
    • GCMS Series: GCMS-TQ8050 NX, GCMS-QP2010 Ultra, GCMS-QP2020 NX
  8. JEOL:
    • AccuTOF Series: AccuTOF DART, AccuTOF GCx, JMS-T100LC
  9. LECO:
    • Pegasus Series: Pegasus BT, Pegasus GC-HRT 4D, Pegasus BT 4D
    • TruTOF Series
  10. Hitachi: NanoFrontier LD, Chromaster

Longi Electromechanical has nearly 30 years of experience in repairing mass spectrometers, enabling quick repairs for various instruments. Additionally, we recycle and sell used mass spectrometers. Welcome to consult.

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 Leak Detector:Overview,Brand,Maintenance Guide, And Repair Services

I. Introduction

A leak detector is a device used to detect leaks in systems containing air, gases, or liquids. Its primary function is to detect leak points and measure the amount of leakage by monitoring pressure differences within the system. The working principle of a leak detector is based on pressure difference detection and measurement technology, utilizing sensors to collect pressure data and controllers to analyze the data and provide corresponding alarms or prompts.

II. Types of Leak Detectors

Leak detectors come in various types, categorized by the medium they detect and the principles and technologies they use.

  • By Medium:
    • Gas leak detectors
    • Liquid leak detectors
  • By Principle and Technology:
    • Pressure difference method: Compares the pressure difference between the object being tested and the environment.
    • Concentration change method: Detects changes in gas concentration around the object.
    • Sound or acoustic wave method: Detects specific sounds or acoustic waves produced during leakage.

III. Usage Method

  1. Power On: Ensure the leak detector is properly connected to the power source and turn it on.
  2. Initialization and Calibration: In a vacuum environment, start the vacuum pump and wait for a stable detection environment (e.g., 10 minutes). Gas leak detectors automatically calibrate upon startup to ensure accuracy.
  3. Measurement: Place the probe at the detection point and observe the numerical changes on the display. If a leak occurs, the reading will increase and may trigger an alarm.
  4. Data Analysis: Judge the leak situation and location based on the readings and analysis results displayed.

IV. Common Faults and Repair Methods

  1. Instrument Unable to Start or Function Normally
    • Causes:
      • Poor power connection or damaged power cord.
      • Insufficient battery power or aged battery.
      • Faulty control panel or buttons.
    • Repair Methods:
      • Check power connection and cord integrity.
      • Check battery power and replace or recharge as needed.
      • Inspect the control panel and buttons for damage or incorrect operation.
  2. Inaccurate or False Detection Results
    • Causes:
      • Insufficient instrument precision or lack of calibration.
      • Damaged or contaminated sensors.
      • Unstable or impure gas source.
    • Repair Methods:
      • Calibrate the instrument to ensure precision.
      • Inspect sensors for damage or contamination, and clean or replace as necessary.
      • Ensure a stable and pure gas source, avoiding operations that may affect its stability.
  3. Insensitive Leak Detection
    • Causes:
      • Incorrect instrument sensitivity settings.
      • Loose connection between the probe and the object being tested.
      • Aged or damaged sensors.
    • Repair Methods:
      • Check and adjust instrument sensitivity settings.
      • Ensure a tight connection between the probe and the object.
      • Inspect sensors for aging or damage, and replace as needed.
  4. Display Fault or Abnormality
    • Causes:
      • Loose or damaged display connection cable.
      • Damaged display itself.
    • Repair Methods:
      • Check the display connection cable for security and reconnect if loose.
      • If the display remains abnormal despite a proper connection, replace the display.

V. Preventive Measures and Routine Maintenance

  • Regular Calibration: Periodically calibrate the leak detector to ensure precision and performance.
  • Keep Clean: Maintain the cleanliness and dryness of the leak detector and its accessories, protecting them from dust and moisture.
  • Proper Storage: Store unused leak detectors in a dry, ventilated place, and conduct regular inspections and maintenance.
  • Professional Training: Provide professional training for operators to ensure they can complete detection tasks correctly and swiftly, adhering to operating procedures and precautions.

VI. Brands and Models of Leak Detectors Repaired by Longi Electromechanical Company

  1. Inficon:
    • UL1000 Fab
    • UL5000
    • Protec P3000
    • HLD6000
    • LDS3000
    • Sensistor ISH2000
    • LeakHunter TGF11
  2. Pfeiffer Vacuum:
    • ASM340
    • ASM390
    • ASM310
    • ASM306S
    • ASM102S
    • Adixen ASM142
    • Adixen ASM192T2D
  3. Leybold:
    • Phoenix Quadro
    • Phoenix Magno
    • Phoenix Vario
    • Phoenix L300i
    • Phoenix L500i
    • Phoenix L1000i
  4. Agilent Technologies:
    • Varian VS Series (VS C15, VS C15AB)
    • Varian HLD Series
    • Varian Helitest
    • PHD-4
    • M12
  5. ATEQ:
    • Primus
    • Primus H2
    • F5200
    • F6200
    • F28H
  6. Edwards:
    • Spectron 5000 Series
    • Spectron 6000 Series
    • Spectron 2000 Series
    • Spectron 3000 Series
  7. Oerlikon Leybold Vacuum:
    • UL 200
    • UL 200 Helium
    • UL 1000 Fab
    • UL 1000
    • UL 500
  8. Alcatel (Adixen):
    • ASM182TD+
    • ASM310
    • ASM142
    • ASM340
    • ASM192T2D
  9. LACO Technologies:
    • AMLD-6
    • Titan VSLD
    • Titan HSLD
    • Titan ES
    • Titan ESVL

VII. Company Information

Longi Electromechanical Company has nearly 30 years of experience in repairing leak detectors and can quickly repair various instruments. We also recycle and sell used leak detectors. For more information, please contact us.

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Chromatography Instrument Maintenance Center: Principles, Usage, Brand,and Troubleshooting for Various Chromatographs

I. Introduction to Chromatography Instruments

Chromatography instruments separate and analyze mixtures based on the physicochemical properties of their components. Common types include Gas Chromatographs (GC), Online Gas Chromatographs, Liquid Chromatographs (HPLC/UPLC), Ion Chromatographs, PE Atomic Absorption Spectrometers, and Zeeman Effect Atomic Absorption Spectrometers. The core principle involves the distribution or adsorption equilibrium of substances between the stationary and mobile phases to achieve separation. After vaporization in the vaporization chamber, the sample is carried into the column by an inert gas (carrier gas, such as N2, He, etc.). Due to differences in boiling point, polarity, or adsorption properties, components in the sample exhibit different distribution or adsorption behaviors in the column, leading to varying elution times and thus separation. The separated components enter the detector, which converts the presence of sample components into electrical signals proportional to the quantity or concentration of the measured components.

II. Usage Instructions

Startup Preparation:

  • Turn on the gas generator and observe if the pressure gauges for air, hydrogen, and nitrogen reach the specified positions.
  • Turn on the chromatograph power switch and adjust the temperatures of the injector, column, and detector.

Ignition and Sample Injection:

  • When the temperatures reach the set values, ignite the detector flame and adjust the hydrogen flow rate.
  • After the signal stabilizes, quickly inject the sample from the sampling cylinder into the chromatograph using a syringe, and record the peak shape and test data.

Data Processing:

  • Repeat measurements multiple times and calculate the average to improve accuracy.
  • After the test, extinguish the flame, turn off the injector and detector, and wait for the column temperature to drop to room temperature before turning off the chromatograph power.

III. Common Faults and Troubleshooting

Injector Faults:

  • Blockage: Reinstall the injector plunger and clean with a suitable solvent.
  • Leakage: Check and replace the injector seal if aged.
  • Improper Installation: Ensure the injection needle is correctly installed on the injector plunger.

Column Faults:

  • Blockage: Disconnect the column from the detector end, check for bubbles, and attempt reverse flushing or replacement.
  • Contamination: Cut off the contaminated part of the column and re-age or clean it.
  • Reduced Efficiency: Replace the column or perform aging treatment.

Detector Faults:

  • Abnormal Signal: Check and clean the detector nozzle and gas pipeline regularly.
  • Decreased Sensitivity: Adjust detector sensitivity settings and check gas flow rates.
  • Contamination: Use high-temperature aging or solvent cleaning for the detector.

System Leaks:

  • Check instrument connections, seals, or pipelines for tightness and replace damaged parts.
  • Use leak detection solution to check connection points for leaks and ensure instrument sealing.

Background Noise and Baseline Drift:

  • Check for a stable instrument environment and adjust detector sensitivity and baseline.
  • Regularly calibrate the instrument and check the stability of flow rate, temperature, and pressure parameters.

Flow Rate Issues:

  • Check the injection system, flow controller, and column for stable flow.
  • Replace the gas flow control valve or adjust gas flow settings.

Sample Contamination:

  • Prepare clean samples and regularly clean the injector and system.
  • Use pre-columns or guard columns to capture semi-volatile and non-volatile impurities.

IV. Maintenance Precautions

  • Before any maintenance, always turn off the chromatograph power and disconnect from the power source.
  • Use appropriate tools and solvents for cleaning and maintenance to avoid damaging instrument components.
  • Regularly maintain and service the instrument, such as replacing filters and cleaning nozzles and gas pipelines.
  • For complex faults, consult the instrument operation manual or seek assistance from professional technicians.

V. Brands and Models Repaired by Rongji Electromechanical Company

Agilent Technologies:

  • GC: 8890 GC System, 7890B GC System, 8860 GC System
  • HPLC/UPLC: 1290 Infinity II LC System, 1260 Infinity II LC System, 1220 Infinity II LC System
  • GC-MS: 8890 GC/MSD System, 7250 GC/Q-TOF, 7010 Triple Quadrupole GC/MS
  • LC-MS: 6546 LC/Q-TOF, 6470 LC/TQ, 6495B LC/TQ

Thermo Fisher Scientific:

  • GC: TRACE 1310 GC, TRACE 1300 GC
  • HPLC/UPLC: Vanquish UHPLC System, UltiMate 3000 HPLC System
  • GC-MS: TSQ 9000 GC-MS/MS, ISQ 7000 Single Quadrupole GC-MS
  • LC-MS: Orbitrap Exploris 240, TSQ Altis Triple Quadrupole, Q Exactive HF-X

Shimadzu:

  • GC: Nexis GC-2030, GC-2010 Plus
  • HPLC/UPLC: Nexera X2 UHPLC, Prominence HPLC
  • GC-MS: GCMS-QP2020 NX, GCMS-TQ8050 NX
  • LC-MS: LCMS-8050, LCMS-8060

Waters:

  • HPLC/UPLC: ACQUITY UPLC H-Class PLUS, ACQUITY Arc System, Alliance HPLC System
  • LC-MS: Xevo TQ-S micro, Xevo G2-XS QTof, SYNAPT XS

PerkinElmer:

  • GC: Clarus 690 GC, Clarus 580 GC
  • HPLC/UPLC: Flexar UHPLC, Flexar HPLC, LC-2030C
  • GC-MS: Clarus SQ 8 GC/MS
  • LC-MS: QSight 220 Triple Quad

Bruker:

  • GC-MS: SCION TQ, SCION SQ
  • LC-MS: timsTOF Pro, maXis II

SCIEX:

  • LC-MS: TripleTOF 6600, Triple Quad 7500, X500R QTOF

Hitachi High-Tech:

  • HPLC/UPLC: Chromaster HPLC, LaChromUltra

JASCO:

  • HPLC/UPLC: LC-4000 Series, X-LC Series

LECO:

  • GC: Pegasus BT GC-TOFMS, Pegasus 4D GCxGC-TOFMS

Tianmei (Selian):

  • GC: SCION 8300 GC, SCION 8500, Selian 436i/456i, GC7980, GC7980Plus, GC7900

Varian (acquired by Agilent):

  • GC: CP-3800, CP-3900, Varian 450-GC, Varian 490-GC
  • HPLC: Varian ProStar 210 HPLC, Varian ProStar 218 HPLC, Varian ProStar 335 HPLC, Varian 940-LC
  • GC-MS: Varian Saturn 2000 GC/MS, Varian Saturn 2200 GC/MS, Varian 450-GC/320-MS, Varian 431-GC/210-MS
  • LC-MS: Varian 1200-LC, Varian 500-MS LC/MS, Varian 610-MS LC/MS
  • IC: Varian 920-LC

About Rongji Electromechanical Company

With nearly 30 years of experience in repairing chromatography instruments, Rongji Electromechanical Company offers swift and efficient repairs for various types of chromatographs. Additionally, we recycle and sell used chromatographs. For more information, please contact us.

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Total Phosphorus and Total Nitrogen Analyzer: Operating Guide and Maintenance

I. Principle of Total Phosphorus and Total Nitrogen Analyzer

The Total Phosphorus and Total Nitrogen Analyzer is a crucial tool in environmental protection and water quality management. It rapidly and accurately measures the total phosphorus (TP) and total nitrogen (TN) content in water samples, providing important data for water quality assessment. The analyzer works based on chemical analysis methods, converting TP and TN in water samples into measurable forms through specific reactions. For instance, TP is often determined using the molybdate colorimetric method, where the absorbance of the blue complex formed is measured; TN may be determined using the Kjeldahl method or nitride reduction method, converting nitrogen into ammonia for measurement.

II. Usage Instructions

Sample Preparation:

  • Collect water samples according to prescribed methods and perform necessary pretreatments, such as filtration and dilution, to ensure sample representativeness and measurability.
  • Avoid contamination and cross-contamination, maintaining sample stability.

Parameter Setting:

  • Reasonably set analyzer parameters, such as detection wavelength, titration volume, and reagent ratio, based on the TP and TN measurement range.

Instrument Calibration:

  • Calibrate the analyzer before sample measurement to eliminate instrument background effects and external interference, ensuring measurement accuracy and comparability.

Measurement Operation:

  • Follow the analyzer’s instruction manual, adding samples and reagents in a specific order and initiating the measurement program.
  • Adhere to operational norms and safety requirements to ensure reliable and stable results.

Result Calculation and Analysis:

  • Use corresponding calculation formulas to compute TP and TN content based on analyzer output, performing unit conversions (e.g., mg/L).
  • Analyze and evaluate data according to measurement results and relevant standards, assessing water sample quality and implementing appropriate environmental protection and water management measures.

III. Common Faults and Repair Methods

Inaccurate Measurement Results:

  • Check if the instrument is correctly calibrated and ensure proper sample collection and handling. Consult the manufacturer or professionals if needed.

Unstable Data Transmission:

  • Check network connection stability and avoid signal interference. Ensure compatibility between the instrument and data processing software. Consider changing the network environment or upgrading software if necessary.

Instrument Alarm:

  • View device alarm messages to understand the fault type. Take corresponding measures based on the cause. If unable to resolve the issue, contact professional maintenance personnel.

Instrument Aging and Damage:

  • Regularly maintain and service the instrument, including cleaning and calibration, following its lifespan and maintenance cycle. Long-term use or improper maintenance can lead to aging and damage, affecting measurement accuracy.

Environmental Interference:

  • Control changes in environmental factors, such as temperature, humidity, and lighting, during instrument use. These factors may impact measurement results and stability. Perform corrections and adjustments as needed.

IV. Brands and Models Repaired by Longi Electromechanical Company

  1. Shimadzu:
    • TNP-4200, TOC-L Series (with TNM-L)
    • TOC-4200 (with TNM-4200)
  2. Hach:
    • Phosphax sigma
    • Phosphax sc
    • Nitratax plus sc
  3. Thermo Fisher Scientific:
    • Gallery Plus discrete analyzer
    • Gallery discrete analyzer
  4. Skalar:
    • SAN++ Continuous Flow Analyzer
    • BluVision Discrete Analyzer
  5. SEAL Analytical:
    • AQ400 Discrete Analyzer
    • AQ300 Discrete Analyzer
    • AutoAnalyzer 3 HR
  6. Metrohm:
    • 870 Compact IC flex (with 850 Professional IC)
  7. YSI (Xylem Analytics):
    • YSI 9300 Photometer
    • YSI 9500 Photometer
  8. PerkinElmer:
    • NexION 2000 ICP-MS
  9. Horiba:
    • Aqualog
  10. Analytik Jena:
    • multi N/C Series (multi N/C 2100/3100/UV HS TOC/TN analyzer)

V. About Longi Electromechanical Company

With nearly 30 years of experience in repairing Total Phosphorus and Total Nitrogen Analyzers, Rongji Electromechanical Company offers quick and efficient repairs for various instruments. Additionally, we recycle and sell used analyzers. For more information, please contact us.

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 Comprehensive Guide to Scanning Electron Microscope (SEM): Overview, Usage, Faults, Brand,and Repair

I. Principle of Scanning Electron Microscope

1. Electron Optical System:

  • Components: Electron gun, electromagnetic lens, scanning coils, and sample chamber.
  • Function: The electron gun generates a high-energy electron beam, which is focused by the electromagnetic lens and raster-scanned across the sample surface.

2. Signal Detection and Processing:

  • Interaction: Electron beam interacts with the sample to produce signals such as secondary electrons, backscattered electrons, and characteristic X-rays.
  • Detection: These signals are received by detectors and converted into electrical signals.
  • Imaging: The signals are amplified and displayed as images through the display system.

3. Vacuum System:

  • Purpose: Ensures stability of the electron beam and prevents sample contamination.
  • Components: Vacuum pump and vacuum column.
  • Function: Generates and maintains high vacuum within the sample chamber.

II. Usage Method for Scanning Electron Microscope

  1. Startup Preparation:
    • Check power supply, cooling water, vacuum pump, and other connections.
    • Ensure a clean and dust-free working environment.
  2. Sample Preparation:
    • Clean, cut, and coat the sample as required.
    • Ensure a flat and contaminant-free sample surface.
  3. Sample Installation:
    • Place the prepared sample on the sample holder.
    • Install it in the SEM sample chamber.
  4. Vacuum Pumping:
    • Use the vacuum pump to achieve the required vacuum level.
  5. Device Startup and Parameter Setting:
    • Start the SEM device.
    • Open the software interface.
    • Set parameters such as accelerating voltage, magnification, and scanning speed.
  6. Focusing and Calibration:
    • Adjust the objective and lens for focusing.
    • Perform necessary calibration.
  7. Observation and Photography:
    • Use software features to adjust image details and position.
    • Observe and capture images.
  8. Data Analysis and Saving:
    • Analyze images (e.g., measure dimensions, calculate areas).
    • Save the results.

III. Common Faults and Repair Methods

  1. ** Flickering or Blurred Display/Image**:
    • Causes: Low resolution, fast scanning speed, power issues, or loose connections.
    • Solutions: Adjust resolution, slow down scanning speed, check power and connection cables.
  2. Device Failure to Start:
    • Causes: Power control issues, blown fuse, faulty switching power supply.
    • Solutions: Check power control, replace fuse, repair or replace switching power supply.
  3. Filament Failure to Turn On:
    • Causes: Unrecognized high-voltage box, faulty switching power supply.
    • Solutions: Check high-voltage box fiber and power input, repair or replace switching power supply.
  4. Unclear Image:
    • Causes: Incorrect contrast settings, dirty sample surface, autofocus issues.
    • Solutions: Adjust contrast, clean the sample, check and repair autofocus.
  5. Software Conflict or System Incompatibility:
    • Causes: Incompatible operating system or software version conflict.
    • Solutions: Update OS and software, or choose more compatible software.

IV. Precautions

  • Maintain a clean, vibration-free, and electromagnetic interference-free environment.
  • Ensure precise sample preparation.
  • Set parameters reasonably based on sample properties and observation needs.
  • Handle with care, follow operating procedures and safety requirements.

V. Brands and Models of SEMs Repaired by Longi Electromechanical Company

  1. Thermo Fisher Scientific (FEI):
    • Helios G4 UX DualBeam
    • Helios G4 CX DualBeam
    • Apreo 2 SEM
    • (Additional models listed…)
  2. JEOL:
    • JSM-7900F
    • JSM-7800F
    • (Additional models listed…)
  3. Hitachi High-Tech:
    • SU9000
    • SU8700
    • (Additional models listed…)
  4. Carl Zeiss:
    • GeminiSEM 500
    • GeminiSEM 300
    • (Additional models listed…)
  5. Tescan:
    • Mira3
    • Mira4
    • (Additional models listed…)
  6. Phenom-World (Thermo Fisher Scientific):
    • Phenom Pharos
    • Phenom ProX
    • (Additional models listed…)
  7. COXEM:
    • EM-30AX Plus
    • CX-200Plus
    • (Additional models listed…)
  8. Nanoscience Instruments:
    • Apreo S
    • Verios G4
    • (Additional models listed…)
  9. Rigaku:
    • nano3DX
    • XtaLAB Synergy-R
    • (Additional models listed…)
  10. Aspex Corporation:
    • Explorer
    • Personal SEM
    • (Additional models listed…)
  11. Leica Microsystems:
    • EM ACE600
    • EM ACE900
    • (Additional models listed…)
  12. Nikon:
    • Eclipse LV150N
    • Eclipse LV100ND
  13. Bruker:
    • ContourGT
    • Contour Elite
    • JPK NanoWizar

VI. About Longi Electromechanical Company

With nearly 30 years of experience in SEM repair, Longi Electromechanical Company offers quick and efficient repairs for various instruments. Additionally, we recycle and sell used SEMs. Welcome to consult us for more information.

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Rheometer: Principles, Brand,Usage, Common Faults, and Maintenance

1. Principles of Rheometer

A rheometer is an instrument used to measure the rheological properties of fluids under different conditions. Its measurement principles are based on applying stress or strain to the fluid and measuring the fluid’s response under these conditions. The specific principles include:

  • Rotational Rheometer: By rotating the measuring element (such as a rotor or cone), shear strain is generated in the fluid, and the required torque or resistance is measured to determine the fluid’s viscosity, shear stress, and rheological characteristics.
  • Capillary Rheometer: The fluid flows through a capillary tube, and its viscosity and rheological behavior are studied by measuring the pressure drop and flow rate.
  • Oscillatory Rheometer: Oscillatory strain or stress is applied to the fluid, and the fluid’s elastic modulus, viscous modulus, and damping characteristics are measured.
  • Tensile Rheometer: Tensile strain is applied to the fluid, and its tensile properties are measured.
  • Cone-Plate Rheometer: Using a cone-plate structure, shear strain is generated in the fluid, and the fluid’s viscosity and rheological characteristics are measured.

2. Usage of Rheometer

The usage of a rheometer typically includes the following steps:

Startup Preparation:

  • Turn on the air compressor (air valve closed).
  • Allow air pressure to rise to the standard value (e.g., 5-8 bar).
  • Open the air valve.
  • Turn on the constant temperature water bath (ensure external circulation mode).
  • Turn on the main power supply and confirm the status of the main unit.
  • After self-check, press “ONLINE” to turn off the indicator light and initialize the displacement.
  • Open the rheometer software, press “ONLINE” to turn on the indicator light, and initialize the connection.

Experimental Operation:

  • Install the measuring jig and sample.
  • Set experimental parameters such as temperature, rotation speed, stress, etc.
  • Start the experiment and record data.

Experiment Completion:

  • Remove the measuring jig and clean the jig and cylinder.
  • Turn off the main power supply, water bath, and air compressor.
  • Organize the experimental instruments and equipment.

3. Common Faults and Maintenance Methods

The rheometer may encounter the following common faults during use, and the corresponding maintenance methods are as follows:

  • Sample Not Flowing or Unstable Flow:
    • Cause: Insufficient sample volume, too thick sample, bubbles in the sample, or sample not fully melted.
    • Maintenance Method: Increase sample volume, reduce sample thickness, centrifuge or filter the sample, ensure the sample is fully melted at the test temperature.
  • Poor Repeatability of Test Results:
    • Cause: Unstable sample properties, instrument fault, improper operation, or environmental factors.
    • Maintenance Method: Use a more stable sample, inspect and repair the instrument, recheck the operation process, control environmental factors.
  • Large Deviation in Test Results:
    • Cause: Uneven sample, improper operation, instrument fault, or inaccurate test conditions.
    • Maintenance Method: Use a more uniform sample, recheck the operation process, inspect and repair the instrument, adjust test conditions.
  • Instrument Unable to Start or Automatically Stops:
    • Cause: Power failure, internal instrument fault, safety protection mechanism.
    • Maintenance Method: Check the power plug and power cord, inspect and repair the internal instrument, check the safety protection mechanism and adjust.
  • No Display or Abnormal Display on the Screen:
    • Cause: Internal instrument fault, power failure, connection issue.
    • Maintenance Method: Inspect and repair the internal instrument, check the power plug and power cord, ensure the connection cables are properly inserted.
  • Abnormal Sound or Odor During Testing:
    • Cause: Abnormal sample properties, instrument fault, improper operation.
    • Maintenance Method: Recheck the operation process, inspect and repair the instrument, check the sample properties.
  • Mechanical Fault:
    • Cause: Broken, worn, or stuck transmission system.
    • Maintenance Method: Inspect and replace transmission components, ensure the transmission system is smooth.
  • Electrical Fault:
    • Cause: Power failure, poor wire contact, control circuit fault.
    • Maintenance Method: Check the power supply, wires, and control circuit, perform necessary repairs or replacements.
  • Temperature Control Fault:
    • Cause: Fault in the temperature control system.
    • Maintenance Method: Inspect and repair the temperature control system, ensure accurate temperature control.
  • Sensor Fault:
    • Cause: Damaged or faulty sensor.
    • Maintenance Method: Inspect and replace the sensor, ensure accurate data collection.
  • Software Fault:
    • Cause: Fault in the control software.
    • Maintenance Method: Reinstall or update the software, ensure the software runs normally.

If any issues are encountered during the use of the rheometer, it is recommended to promptly consult professionals or the manufacturer for resolution.

4. Brands and Models of Rheometers Repaired by Longi Electromechanical

  • Anton Paar:
    1. MCR 302
    2. MCR702 MultiDrive
    3. MCR 502 WESP
    4. MCR502
    5. MCR72
    6. MCR 92
  • TA Instruments:
    1. Discovery HR-3
    2. Discovery HR-2
    3. Discovery HR-1
    4. DHR-1
    5. DHR-2
    6. DHR-3
    7. AR-G2
  • Malvern Panalytical:
    1. Kinexus Pro+
    2. Kinexus Ultra+
    3. Kinexus Lab+
    4. Rosand RH2000
    5. Rosand RH7
    6. Rosand RH10
    7. Rosand RH50
  • Brookfield (Ametek Brookfield):
    1. RSX Rheometer
    2. RST Rheometer
    3. DVNext Rheometer
    4. PFT Powder Flow Tester
    5. CT3 Texture Analyzer
  • Thermo Scientific:
    1. HAAKE MARS 60
    2. HAAKE Viscotester iQ
    3. HAAKE RotoVisco 1
    4. HAAKE RheoStress 1
  • Anton Paar Physica:
    1. MCR 302 WESP
    2. MCR 502 TDR
    3. MCR 102
    4. MCR 302 MultiDrive
  • ATS RheoSystems:
    1. RST Controlled Stress Rheometer
    2. Viscoanalyzer, EML Rheometer
  • Rheosense:
    1. m-VROC
    2. e-VROC
    3. microVISC
  • Thermo Fisher Scientific:
    1. HAAKE Viscotester 550
    2. HAAKE MARS iQ, HAAKE Viscotester 3
  • Reologica Instruments:
    1. Stresstech HR
    2. Kinexus DSR-E
    3. Bohlin Gemini 2

Longi Electromechanical has nearly 30 years of experience in repairing rheometers and can quickly repair various types of instruments. Additionally, we recycle and sell various used rheometers. Welcome to consult.

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Trace Oxygen Analyzer: Principles, Brands & Models, Usage, and Troubleshooting Guide

I. Classification of Trace Oxygen Analyzer Principles

Trace oxygen analyzers are crucial tools for detecting minute amounts of oxygen in the environment. Their principles are mainly categorized into fuel cell and zirconia methods.

1. Fuel Cell Trace Oxygen Analyzer

  • Principle: Utilizes a fully sealed fuel cell oxygen sensor consisting of highly active oxygen and lead electrodes immersed in a KOH solution. Oxygen molecules in the sample gas diffuse through a polymer membrane to the oxygen electrode, where they undergo an electrochemical reaction. The generated current is proportional to the oxygen content in the sample gas.
  • Advantages: Maintenance-free, stable and reliable sensor, no need for regular cleaning or replacement.

2. Zirconia Trace Oxygen Analyzer

  • Principle: Employs a zirconia element as the key component of the oxygen detection cell. At high temperatures, oxygen diffuses from the side with higher partial pressure to the side with lower partial pressure, creating a potential difference, which is used to measure oxygen content.
  • Advantages: Wide measurement range, easy to use, long service life.

II. Usage Instructions

  1. Instrument Startup: Ensure the portable trace oxygen analyzer is in normal working condition.
  2. Mobile Detection: Hold the antioxidant and corrosion-resistant detection rod to measure the concentration of trace oxygen gas in the environment.
  3. Data Recording: Utilize the instrument’s storage and memory function to record data per second during detection, facilitating subsequent query and computer printing.

III. Common Faults and Troubleshooting Methods

  1. No Response to Sample Gas
    • Cause: Sensor failure.
    • Repair Method: Check instrument connections for normality or replace the sensor.
  2. No Display on Instrument
    • Cause: Fuse burnout or circuit failure.
    • Repair Method: Replace the fuse or send to a professional repair center.
  3. Slow Response or Poor Linearity
    • Cause: Sensor aging, presence of liquids or dust, gas path leakage.
    • Repair Method: Replace the sensor, clean the pipelines, or repair the leakage.
  4. No Indication on Flowmeter
    • Cause: Filter at the inlet is blocked or internal pipelines are clogged.
    • Repair Method: Check the filter screen or send the instrument back to the manufacturer for repair.
  5. High or Low Indication
    • Cause: Signal drift, presence of other interfering gases, inaccurate sensor calibration, gas path leakage.
    • Repair Method: Recalibrate the instrument, filter out other interfering gases, check and repair gas path leakage, replace the sensor.
  6. Garbled Display
    • Cause: Strong external power interference or instrument detection program issues.
    • Repair Method: Add a purified power supply stabilizer or send the instrument to a professional repair center.
  7. Internal Instrument Fault
    • Cause: Associated with fault codes.
    • Repair Method: Refer to the fault code instructions in the instrument manual for targeted troubleshooting.
  8. Power Issues
    • Cause: Poor power cord connection or faulty power socket.
    • Repair Method: Check power cord connection and power socket, and conduct professional repair if necessary.
  9. Ambient Temperature Changes
    • Cause: Large ambient temperature changes, sensor aging or contamination.
    • Repair Method: Avoid using the instrument in environments with large temperature changes, regularly replace or clean the sensor.

IV. Longi Ectromechanical Company Repair Services

Longi Ectromechanical Company, with nearly 30 years of experience in trace oxygen analyzer repair, can quickly repair various types of instruments. The company also offers services for recycling and selling various used analyzers. Below are some of the brands and models that have been repaired:

  • Process Insights: MTO2-2000, ZIRCOMAT, OXYMAT 6
  • ADEV: G1501, OXY ONE, OXY CHECK, OXY MANAGER
  • Pittcon Instruments: POA200, 209 Series, Model 211, Model 212
  • In-Situ: EN-500, RDO PRO-X, Aqua TROLL 600, TROLL 9500
  • Servomex: SERVOPRO MultiExact 4100, SERVOPRO MonoExact DF310E, SERVOPRO 4900 Multigas, SERVOPRO NanoChrome
  • Teledyne Analytical Instruments: 3000TA, 3000T Series, 3000MB Series, 3000MA
  • AMETEK: 2000H, 3000TA, 3000MA, ta7000
  • Michell Instruments: XZR400, XZR500, XTP601, XZR200
  • Systech Illinois: EC900, EC923, EC91, EC92DIS
  • Mettler-Toledo: Thornton 499AO, 5900 Series, 5500 Series, 4900 Series
  • Yokogawa: ZR22, ZR202, ZR402, AV550G
  • Delta F Corporation: DF-150E, DF-500, DF-560E, DF-745
  • Analytical Industries Inc. (AII): GPR-1500, GPR-2500, GPR-3100, GPR-4100
  • GE Analytical Instruments: Oxy.IQ, Oxy.IQ II

For trace oxygen analyzer repair services, please contact Longi Ectromechanical Company.