How to select temperature sensors for the oil industry? 5 key points that both procurement personnel and technicians should know
Problems such as inaccurate temperature measurement, frequent damage, and signal interference in Temperature Sensors under oil working conditions can actually be avoided during the selection stage.
- Why are Temperature Sensors in the oil industry "difficult to select"?
The temperature measurement environment in the oil industry has its own particularities. Unlike ordinary industrial scenarios, in the oil drilling, refining, storage, and transportation processes, multiple adverse factors often coexist simultaneously:
- Extensive temperature fluctuations:ranging from ambient temperature to over 150℃, and in some process sections even higher.
- Complex medium:crude oil, refined oil, chemical media, corrosive gases
- Vibration and shock: The drilling platform, compressor room, etc. are experiencing significant vibrations.
- Explosion-proof requirements:In areas prone to fire and explosion, explosion-proof sensors must be used.
- Electromagnetic interference: Signal interference caused by high-power motors and frequency conversion equipment
Under these operating conditions, ordinary temperature sensors are prone to experiencing drift, breakage, delayed response, or even complete failure. For procurement and technical personnel, choosing the right temperature sensor directly affects the safe operation of the device and the reliability of the measurement data.
So, how should one choose A Temperature Sensor for the oil industry?
- Five Core Dimensions for Selecting Temperature Sensors in the Oil Industry
- Dimension 1: Temperature Measurement Principle - Thermoresistor or Thermocouple?
| Comparison Items: | Thermoresistor (Pt100) | Thermocouple
|
| Common Measurement Range | -200~500℃ | 0~1300℃
|
| Accuracy | High | General |
| Stability | Good | General |
| Response Speed | Slower | Faster |
| Price | Moderate | Lower |
| Applicable Scenarios in the Oil Industry | Pipelines, Storage Tanks, Reaction Vats (Medium and Low Temperature) | Cracking Furnaces, Heating Furnaces (High Temperature)
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Recommendation: For the 0-150℃ range, Pt100 thermoresistor is the preferred choice, as it offers high accuracy and good stability, meeting the majority of petroleum process temperature measurement requirements.
- Dimension 2: Installation Method - Flange or Thread?
In petroleum applications, the installation method of the temperature sensor directly determines the convenience of subsequent maintenance.
| Installation method | Advantages | Disadvantages | Applicable scenarios |
| Flange installation | Strong, good sealing, easy to disassemble | Higher cost, large space occupation | Pipelines, containers, pressure-bearing conditions |
| Threaded installation | Compact size, low cost | Prone to loosening in vibration environments | Equipment body, non-vibration conditions
|
Recommendation: For scenarios such as oil pipelines, reaction vessels, and pressure vessels, flange installation is recommended as it provides reliable sealing and is convenient for maintenance and replacement.
- Dimension 3: Cable Selection - Don't Ignore This "Small Component"
Many faults of temperature sensors do not originate from the probes themselves, but from the cables. In oil-related conditions, the cables are constantly exposed to oil contamination and high temperatures, and ordinary cables will quickly age, crack, and experience signal attenuation.
Recommended cable type:
- AFPF (Fluoroplastic Insulated Shielded Cable):Resistant to oil, high temperature (-40 to 200℃), and interference-proof. It is an ideal choice for petroleum instruments.
- Glass fiber cables:Have higher temperature resistance (up to over 400℃), but are not resistant to oil.
- Ordinary PVC cables:Not recommended. They are not resistant to oil or heat.
Suggestion: In cases involving petroleum media or oil-contaminated environments, it is essential to choose AFPF or equivalent oil-resistant cables.
- Dimension 4: Explosion-proof rating - The safety red line must not be crossed
Most petrochemical areas are classified as flammable and explosive locations, and therefore, explosion-proof temperature sensors must be used.
Suggestion: If unsure, choose Ex d IICT6 explosion-proof type, which has the widest application range and is easier to pass the inspection.
- Dimension 5: Output Signal - Matching with the Control System
| Signal Type | Advantages | Disadvantages | Applicable Scenarios |
| Pt100 Resistance Signal | High accuracy, no conversion error | Line length limited | Short distance, high precision requirement |
| 4-20mA | Strong remote transmission capability, anti-interference | Requires transducer, with conversion error | Long-distance transmission, PLC/DCS system |
| RS485/Modbus | Digital signal, multi-channel acquisition | Complex wiring, high cost | Intelligent acquisition system
|
Recommendation: For general DCS/PLC systems, 4-20mA output is the most common; if there is an intelligent acquisition module on-site, Pt100 can be directly connected.
- Typical Application Scenarios and Selection Suggestions for Temperature Sensors in the Petroleum Industry
| Application Scenario | Recommended Selection Scheme
|
| Temperature at the inlet and outlet of drilling fluid in oil wells | PT100 thermal resistance, flange installation, AFPF cable, non-explosion-proof type (for non-explosion-proof areas)
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| Temperature of the reaction vessel in the refining and chemical industry | PT100 or thermocouple (depending on the temperature), flange installation, explosion-proof Ex d, 4-20mA output
|
| Temperature of oil storage tanks in the oil depot | PT100 thermal resistance, flange installation, multi-point temperature measurement option, explosion-proof Ex d
|
| Temperature of oil pipelines | PT100 thermal resistance, flange or threaded installation, protection grade above IP65
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| Temperature of the production wellhead/production tree | PT100 thermal resistance, miniaturized design, explosion-proof Ex d, corrosion-resistant housing Weilian Fengran Sensor Technology specializes in the research and production of industrial temperature sensors. Its products are widely used in the fields of petroleum, chemical industry, power, and metallurgy.
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- Typical supporting products in the petroleum industry:
Install Pt100 temperature sensor (0 - 150℃, AFPF oil-resistant cable)
Explosion-proof integrated temperature transmitter (4-20mA output)
Support small-batch customization, OEM/ODM cooperation, and provide selection technical support.