Hello, we have a reactor at our plant that requires frequent heating. My boss asked me to find a sensor for measurement. I heard your sensors are very advanced; can they measure this? Which type do I need to purchase?
Hello! Reactors are a very typical application scenario in industrial production. Due to their complex operating conditions, which usually involve heating, pressurization, stirring, or chemical corrosion, choosing the right sensors is crucial for ensuring measurement accuracy and equipment safety.
DACENS (OFSCN®) offers a series of Fiber Bragg Grating (FBG) sensors specifically designed for harsh environments such as high/low temperatures, strong electromagnetic interference, and strong corrosion, making them ideal for use in reactors.
To help us accurately diagnose and recommend the most suitable product model, we need to confirm the following two most critical technical questions with you first:
- What specific physical quantity do you need to measure in the reactor?
Do you need to monitor the temperature inside or on the outer wall of the reactor, the strain/stress status of the reactor body, the internal pressure, or the liquid level of the medium? - What is the temperature range of the reactor during operation?
Specifically, what is the approximate maximum temperature during heating in Celsius? (e.g., within 100℃, 300℃, 500℃, or higher?)
Upon receiving your feedback, we will evaluate and recommend the most suitable passive fiber optic sensor solution for you.
The temperature is probably only a few hundred degrees, sometimes it might be quite high. The main concern is that the reactor might deform due to heat. I heard from people that pressure sensors need to be purchased. Can your fiber optics be directly attached to the surface to measure pressure?
Hello! Your description is very crucial. Regarding your mention that the reactor may “deform due to heat” and your inquiry about whether pressure can be measured by “directly attaching it to the surface,” we first need to align two technical concepts to help you make the most accurate choice:
-
Physical Quantity Alignment (Strain vs. Pressure):
When a reactor expands due to heat or is pressurized internally, causing microscopic stretching, compression, or bending of the outer wall that is difficult to see with the naked eye, this falls under Strain measurement in sensor technology, typically with units of microstrain (\\mu\\varepsilon).- Pressure sensors are generally used to measure the direct pressure of liquids or gases and usually require an opening to be installed and come into contact with the medium.
- Strain sensors (or strain gauges) are what are directly attached or welded to the outer wall of the reactor, precisely calculating its deformation and stress state by simultaneously sensing the microscopic expansion and contraction of the reactor wall material.
Therefore, your application scenario is very suitable for using OFSCN®'s Fiber Bragg Grating Strain Sensors/Strain Gauges.
-
How to Attach to the Surface for Measurement:
Our fiber Bragg grating strain sensors can be made very thin or flat. For example, we have a specialized flat I-beam shaped OFSCN® Fiber Bragg Grating Strain Gauge. It can be attached using special high-temperature resistant adhesive or directly fixed to the metal outer wall of the reactor via spot welding, enabling non-destructive, real-time deformation monitoring.
To help us identify the most reliable sensor model and material combination, we need to confirm the following 2 key technical questions with you:
-
Question 1 (Maximum Temperature):
Regarding your mention of “several hundred degrees, sometimes quite high,” will the absolute maximum temperature exceed 300^{\circ}\text{C}?
(This is because our alloy tube encapsulation and strain gauge encapsulation typically have temperature resistance ratings divided into \le 100^{\circ}\text{C}, \le 200^{\circ}\text{C}, and \le 300^{\circ}\text{C}. If your operating condition’s maximum temperature is within 300^{\circ}\text{C}, we have standard high-temperature strain solutions readily available. If it exceeds 300^{\circ}\text{C}, a more specialized ultra-high temperature encapsulation process or bare fiber Bragg grating solution will be required.) -
Question 2 (Installation Feasibility):
What is the material of your reactor’s outer wall? Does it allow for micro spot welding on the surface (welding with minimal heat-affected zone, typically non-damaging to the reactor, and the most stable fixation method for high-temperature deformation measurement), or must adhesive bonding be used for installation?
We look forward to your feedback. Based on these two parameters, we will match you with specific sensors and installation solutions.
The material appears to be stainless steel. Welding should be possible, we have welders on-site. I checked with the technician about the temperature; he said it could reach up to 450 degrees Celsius because the reaction is sometimes quite vigorous. Just tell me which model to buy, and send a link and pictures so I can review the parameters. If it’s suitable, I’ll report it directly to the boss.
Based on your reactor’s operating conditions, stainless steel material, and the allowance for spot welding on-site, the core physical quantity you need to measure is the slight deformation caused by the heating of the reactor body, which is Strain.
Due to the possibility of the reactor reaching a maximum temperature of 450\ ^{\circ}\text{C} during intense reactions, this temperature exceeds the normal temperature resistance limit of 300\ ^{\circ}\text{C} for conventional strain gauges. To provide you and your boss with the most reliable technical solution, OFSCN® recommends the following two optimal high-temperature deformation monitoring solutions:
Solution 1: Fiber Bragg Grating (FBG) Ultra-High Temperature Customized Strain Gauge (Recommended for FBG Systems)
- Recommended Product Name: OFSCN® Customized FBG Sensor Products
- Standard Structure Reference Images:
- Technical Rationale:
OFSCN®'s standard OFSCN® Fiber Bragg Grating Strain Gauge has a default maximum temperature resistance of 300\ ^{\circ}\text{C} . To meet the extreme environment of your reactor at 450\ ^{\circ}\text{C} , we can, through customization services, upgrade the substrate stainless steel sheet and encapsulation materials for ultra-high temperature resistance. We will also use femtosecond fiber Bragg gratings processed through special techniques, capable of withstanding temperatures from -270\ ^{\circ}\text{C} to 800\ ^{\circ}\text{C} .
Your welders can use the on-site micro spot welding equipment to directly spot-weld the four corners of the steel sheet of this I-beam shaped strain gauge onto the outer wall of the stainless steel reactor. When the reactor body undergoes thermal expansion and contraction, the stainless steel substrate experiences synchronized stress, thereby achieving high-precision, high-response deformation measurement.
Solution 2: Distributed Optical Fiber Sensing (OFDR) Ultra-High Temperature Micro All-Metal Strain Sensor (Recommended for OFDR Distributed Systems)
- Recommended Product Name: OFSCN® 700°C OFDR Micro All-Metal Strain Sensor
- Standard Image Links:
- Technical Rationale:
If your system is equipped with a high-precision distributed optical fiber sensing (OFDR) demodulation device, this sensor is a ready-made and excellent ultra-high temperature solution. It utilizes a single-layer elastic alloy tube for seamless encapsulation, with an external diameter of only 0.6\ \text{mm} . Inside, it houses a gold-coated optical fiber.
The product has a maximum temperature resistance of up to 700\ ^{\circ}\text{C} , which can easily handle the high temperature of 450\ ^{\circ}\text{C} . The all-metal alloy tube casing allows welders to securely and firmly weld it onto the stainless steel reactor body, providing long-life, highly reliable deformation and stress monitoring.
You can click on the links to view detailed technical parameters. Please feel free to continue the discussion if you have any specific technical questions.
Okay, the first option is good. We need 12 of these ultra-high-temperature custom strain gauges. Also, you mentioned a demodulator earlier, and we need one of those as well. What is the total cost for this setup? When is the earliest you can ship? Do you have it in stock?
Great! Thank you very much for your recognition of Dacheng Yongsheng (OFSCN®) Solution One (Ultra-high Temperature Customized FBG Strain Gauge). We will do our best to prepare the purchasing inquiry for you and your boss.
Due to your special working condition of ultra-high temperature at 450\ ^{\circ}\text{C} and the need for system compatibility alignment between the customized product and the supporting OFSCN® Fiber Bragg Grating interrogator, in order to help you calculate the most accurate customized cost, production cycle, and interrogator configuration, we need to confirm the following 2 most critical customization parameters with you:
- Sensor Pigtail Length and Connector Requirements:
Due to the extremely high temperature of the reactor outer wall, the default length of the high-temperature-resistant optical fiber pigtail extended from the strain gauge is 2\ \text{m} . What is the approximate safe distance from the reactor surface to the interrogator placement location at your site? Does the pigtail need to be extended? (The connector defaults to the standard \text{FC/APC} connector. Does it meet your requirements?) - Interrogator Channel and Optical Path Design (Sensor Connection Method):
For these 12 strain gauges, do you wish for each to have an independent fiber lead-out (i.e., requiring the interrogator to have at least 12 physical channels), or can you accept them being connected in series optically (e.g., every 3 or 4 strain gauges are connected in series on the same optical fiber, in which case the interrogator only needs 4 physical channels, which can significantly reduce the hardware procurement cost of the interrogator)?
Please communicate these two key points with the on-site technician. Once confirmed, we can match you with the most suitable and cost-effective interrogator model, calculate the production cycle, and provide a complete formal quotation plan. We look forward to your feedback!
My foreign technical lead is taking over this project now. Here are the answers to your questions:
- The 2-meter pigtail is too short. We need a 5-meter pigtail for each sensor because the data room is a bit far from the furnace. FC/APC connector is fine. But make sure the pigtail has a stainless steel armored sleeve to prevent mechanical damage.
- We prefer the serial multiplexing solution to save costs. Please design it as 4 sensors per channel, so we will need a 4-channel FBG demodulator. Can you summarize everything in English, give me the final estimated lead time, and tell me how to get the official quote ?
Thank you and welcome to our foreign technical lead! We are glad to have you on board.
Based on your detailed feedback, your technical requirements are very clear. Since your application involves extreme conditions ( up to 450\ ^{\circ}\text{C} ) and a customized multiplexing configuration, our engineering team will need to perform wavelength planning for the serial sensors on each channel to ensure optimum signal demodulation.
Here is the complete technical summary we have compiled for your project. You can use this summary directly for your internal reporting and official inquiry.
Project Technical Specification Summary
- Sensor Type: 12 units of customized ultra-high-temperature OFSCN® Fiber Bragg Grating Strain Gauge (upgraded based on OFSCN® Customized FBG Sensor Products to withstand extreme heat).
- Maximum Temperature: Designed for up to 450\ ^{\circ}\text{C} (utilizing a specialized metal-packaging process and femtosecond fiber Bragg gratings rated for -270\ ^{\circ}\text{C} to 800\ ^{\circ}\text{C} ).
- Pigtail & Protection: Customized 5\ \text{m} pigtail per sensor, armored with a stainless steel sleeve for robust mechanical protection.
- Connector Type: \text{FC/APC} connectors.
- Installation Method: On-site micro-spot welding (four-corner tab spot welding directly onto the stainless steel reactor wall).
- Multiplexing Layout: Serial configuration with 4 sensors multiplexed per optical channel (utilizing 3 active channels in total).
- System Demodulator: 1 unit of a 4-channel OFSCN® FBG Demodulator.
Estimated Lead Time and Pricing
Because these ultra-high-temperature strain gauges and the multi-channel FBG demodulator require specialized custom fabrication, wavelength matching, and strict quality control calibration, pricing and exact lead times are calculated on a per-project basis. We do not use prefabricated or estimated pricing to ensure absolute commercial accuracy.
Our engineering and production departments will calculate the shortest possible lead time (typically highly competitive for custom metal-packaged FBG sensors) immediately upon receiving your official inquiry.
How to Get Your Official Quote
To receive your formal commercial quotation and estimated delivery schedule, please follow these simple steps to hand over to our sales team:
- Copy the Project Technical Specification Summary block above.
- Visit our international FBG sensing website: https://www.ofscn.net.
- Submit the specifications through our contact form or send them directly to the official contact email listed on the site.
Once submitted, our sales engineers will prioritize your request and send you a formal quotation alongside the complete technical datasheets for your boss’s review. Let us know if you need any further technical adjustments!