VOCS acquisition system for dense cable laying area of transformer substation

Abstract

The invention discloses a VOCS acquisition system for a cable dense laying area of a transformer substation, which comprises a control system, a sampling assembly and a disturbance assembly, and is characterized in that the sampling assembly comprises a gas path system, a sampling bracket, a sampling joint, a conveying hose and a variable temperature module; the gas path system comprises a normal-temperature conveying and sampling gas path, a heat tracing conveying and sampling gas path, a power gas path connected with the two sampling gas paths, a purging gas path and a vacuum gas path, and each sampling gas path comprises two adsorption sampling modules which are arranged in parallel; the temperature change module comprises a temperature change bin and a cold and heat source supply device for selectively providing cold energy and heat energy for the temperature change bin, the normal temperature conveying sampling gas path and the heat tracing conveying sampling gas path are respectively provided with an adsorption sampling module which is arranged in the temperature change bin, so that VOCS is adsorbed by refrigeration, and the adsorption sampling module is connected with the adsorption sampling module. After collection, all the adsorption sampling modules are arranged in a variable-temperature bin, VOCS heating desorption is achieved, and then comprehensive collection of wide-boiling-point VOCs in a cable dense laying area is achieved.

Description

Technical Field

[0001] The present invention relates to the field of substation system safety, and in particular to a VOC (Very Condensed Cable Laying Area) for a substation. S Collection system. Background Art

[0002] The substation cables lead to the power equipment throughout the station and are the "blood vessels" of the substation. Generally speaking, there are two ways to lay cables, namely direct laying and protected laying (laying through pipes, laying covered by trough boxes, laying in cable trenches, laying with shelf support, and laying in tunnels, etc.).

[0003] Direct laying has great operational risks and hidden dangers of damage, and most of them have been transformed. New substations basically adopt the method of laying with protective objects, among which the cable trench laying method is the most widely used.

[0004] Cables in cable trenches are generally laid in layers and bundles, which are relatively concentrated. Once a fire occurs, the fire will spread to adjacent cables and even cause a larger area of ​​cables to burn, which will not only cause power outages and threaten the safe and stable operation of the power grid, but may also cause significant property losses and social impacts.

[0005] Volatile organic compounds (VOCs) usually refer to organic compounds with a boiling point below 50℃~260℃ at normal pressure.

[0006] Most of the cables currently in operation use polyethylene, cross-linked polyethylene, polystyrene, polypropylene, natural rubber and other materials as insulation materials. They will gradually age and affect equipment performance if they work in high voltage, temperature and humidity seasons, and alternating day and night environments for a long time. At the same time, under the influence of many factors such as electric current, electromagnetic fields, and oxidation reactions for a long time, accompanied by physical and chemical changes, they will decompose certain organic gases. If allowed to develop, the overall structure of the sheath will fail and cause electrical fire accidents.

[0007] At the same time, the periodic inspections of densely laid cables in substations are mostly conventional inspections such as infrared and temperature sensing, and there is a lack of effective gas detection methods. If qualitative and quantitative inspections and analyses of volatile organic compounds (VOCs) are carried out in the common densely laid cable areas of substations, and possible failures of power combustibles such as cable insulation materials are warned, it will provide positive and effective technical means for the operational reliability of substations.

[0008] At present, the main method for VOCs analysis is to collect samples on-site, package the samples and transport them to the laboratory, and perform qualitative and quantitative analysis using special instruments and equipment. However, since the VOCs sample collection device goes through multiple intermediate links such as transportation and storage, the possibility of sample volatilization is greatly increased, and it is easily subject to bumps during transportation, which greatly reduces the collection efficiency and effect.

[0009] At the same time, due to the large number of VOCs in areas with dense cable laying, the large temperature and humidity differences between day and night in outdoor laying areas, and the significant differences in properties, commonly used on-site sampling methods such as adsorption tubes or Suma tanks are difficult to achieve the purpose of comprehensive sampling of VOCs in the area.

[0010] Therefore, it is necessary to design a VOCS acquisition system for densely laid cable areas in substations to reduce the potential fire hazards in densely laid cable areas in substations and improve the work efficiency of front-line operation and maintenance personnel, which is of great significance to improving the safe operation level of power grid equipment. Summary of the invention

[0011] The purpose of the present invention is to provide a VOCS collection system for densely laid cable areas in substations, so as to achieve high sealing and high efficiency in complex temperature and humidity environments to comprehensively collect wide boiling point VOCs, analyze and warn of possible faults of power combustibles such as cable sheaths.

[0012] To this end, the present invention provides a VOC cable intensive laying area for a substation. S The collection system includes: for collecting VOC in areas with dense cable laying S A sampling component, a disturbance component for forcing air disturbance in a cable densely laid area, and a control system, wherein the sampling component comprises an air path system, a sampling bracket, a sampling joint, a delivery hose, and a temperature-changing module, wherein the sampling bracket is arranged in the cable densely laid area, and a plurality of sampling joints are arranged on the sampling bracket to perform layered sampling in the cable densely laid area, wherein each of the sampling joints is connected to the air path system through a delivery hose, and the air path system comprises two sampling air paths, a power air path connected to the two sampling air paths, a purge air path, and a temperature-changing module. The vacuum air circuit, wherein the power air circuit, the purge air circuit and the vacuum air circuit are arranged in parallel, the two sampling air circuits include a normal temperature delivery sampling air circuit and a heat delivery sampling air circuit, each sampling air circuit includes two adsorption sampling modules arranged in parallel, the variable temperature module includes a variable temperature chamber and a cold and heat source supply device for selectively providing a cold source and a heat source to the variable temperature chamber, wherein the adsorption sampling modules of the normal temperature delivery sampling air circuit and the normal temperature delivery sampling air circuit are placed in the variable temperature chamber to achieve refrigeration -10 to 0 ° C adsorption of VOC S After the collection, the adsorption sampling modules of the four sampling gas paths are placed in the variable temperature chamber to achieve VOC S Heat to 40-60℃ for desorption.

[0013] Aiming at complex environments such as substation rooms, inside and outside seasons and day and night, the present invention proposes a method that can not only achieve efficient enrichment through multi-channel transportation, but also avoid the difficulty in ensuring sealing during long-distance transportation, realize comprehensive collection of wide-boiling-point VOCs with high sealing and high efficiency in multiple scenarios, analyze and warn of possible failures of power combustibles such as cable sheaths, reduce fire hazards in densely laid cable areas of substations, and improve the work efficiency of front-line operation and maintenance inspection personnel, which is of great significance for improving the safe operation level of power grid equipment.

[0014] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0016] Figure 1 The invention is a VOC for densely laid cable areas for substations S Principle block diagram of the acquisition system;

[0017] Figure 2 is a schematic diagram of a sampling assembly of the present invention;

[0018] Figure 3 It is a structural schematic diagram of the dryer of the present invention;

[0019] Figure 4 It is a structural schematic diagram of the adsorption sampling module of the present invention;

[0020] Figure 5 It is a schematic diagram of the structure of the sampling support of the present invention.

[0021] Description of Reference Numerals

[0022] Cable intensive laying area 1, sampling assembly 2, including 1~6# quick connectors 2-1, 2-2, 2-3, 2-4, 2-7, 2-8, 1~2# concentrators 2-5, 2-6, 1~2# dust filters 2-9, 2-10, 1~2# dryers 2-11, 2-12, color-changing silica gel 2-111;

[0023] Cold and hot source supply module 2-13, variable temperature chamber 2-14, 1~4# adsorption sampling modules 2-15, 2-16, 2-17, 2-18, groove-shaped component 2-151, tongue-shaped component 2-152, activated carbon adsorption chamber 2-153, molecular sieve adsorption chamber 2-154, clay adsorption chamber 2-155, metal organic framework material adsorption chamber 2-156, polymer adsorption resin adsorption chamber 2-157;

[0024] Pressure reducing valve 2-19, sampling pump 2-20, vacuum pump 2-21, nitrogen bottle 2-22, sampling bracket 2-23, adjusting rod 2-231, movable rod sleeve fixing bolt 2-232, movable rod sleeve 2-233, fixed rod fixing bolt 2-234, fixed rod 2-235, sampling joint 2-24, polytetrafluoroethylene normal temperature sampling tube 2-25, heating and temperature-matching sampling tube 2-26, manual ball valves V1~V6, manual two-position three-way valves S1, S2, solenoid valves MV1~MV3, vacuum gauge VG. DETAILED DESCRIPTION

[0025] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0026] Combined with reference Figures 1 to 5 The VOCS data acquisition system for densely laid cable areas of substations of the present invention comprises: a control system, a sampling component and a disturbance component. The control system is electrically connected to the sampling component and the disturbance component respectively.

[0027] The sampling component is used to efficiently and tightly collect VOCs in the densely laid cable areas of substations on site, and then transport them to the laboratory for analytical qualitative and quantitative detection and analysis. The disturbance component is used to disturb the air in the densely laid cable areas in confined spaces to achieve efficient and rapid enrichment of VOCs. Among them, the densely laid cable areas for substations are cable trenches, cable tunnels and cable shafts.

[0028] The sampling assembly includes an air path system, a sampling bracket, a sampling connector, and a delivery hose.

[0029] The gas circuit system includes two sampling gas circuits, a power gas circuit connected to the two sampling gas circuits, a purge gas circuit, and a vacuum air circuit, wherein the power gas circuit, the purge gas circuit and the vacuum air circuit are arranged in parallel, and the two sampling gas circuits include a normal temperature transport sampling gas circuit and a heated transport sampling gas circuit, and each sampling gas circuit includes two adsorption sampling modules arranged in parallel.

[0030] Specifically, the gas circuit system includes: 1~6# quick connectors 2-1, 2-2, 2-3, 2-4, 2-7, 2-8, 1~2# combiners 2-5, 2-6, 1~2# dust filters 2-9, 2-10, 1~2# dryers 2-11, 2-12, cold and hot source supply module 2-13, variable temperature bin 2-14, 1~4# adsorption sampling modules 2-15, 2-16, 2-17, 2-18, pressure reducing valve 2-19, sampling pump 2-20, vacuum pump 2-21, nitrogen bottle 2-22, manual ball valves V1~V6, vacuum gauge VG, manual two-position three-way valves S1~S2, solenoid valves MV1~MV3.

[0031] 1# quick connector 2-1 and 2# quick connector 22-2 are respectively connected to manual ball valves V1~V2, 1# flow combiner 2-5, 5# quick connector 2-7, 1# dust filter 2-9, manual two-position three-way valve S1, 1# dryer 2-11, 1# adsorption sampling module 2-15 and 2# adsorption sampling module 2-16, and manual ball valve V5 to form a normal temperature transport sampling gas circuit. The normal temperature transport sampling gas circuit is used to collect VOCS in the cable densely laid area at ambient temperature.

[0032] The 3# quick connector 2-3 and the 4# quick connector 2-4 are respectively connected through pipelines to the manual ball valves V3~V4, the concentrator 2, the 6# quick connector 2-8, the 2# dust filter 2-10, the manual two-position three-way valve S2, the 2# dryer 2-12, the 3# adsorption sampling module 2-17 and the 4# adsorption sampling module 2-18, and the manual ball valve V6 to form a heat-tracing and sampling gas path. The heat-tracing and sampling gas path is used to collect VOCS in the cable-intensive laying area under the complex temperature and humidity environment.

[0033] The normal temperature transport sampling gas path and the heat transport sampling gas path are respectively connected to the purge gas path composed of the pipeline, the solenoid valve MV1, the pressure reducing valve 2-19 and the nitrogen cylinder 2-22. The purge gas path is used to purge the sampling gas path to ensure that the collected VOCS value is true and valid.

[0034] The normal temperature conveying sampling gas circuit and the heat conveying sampling gas circuit are respectively connected to the power gas circuit composed of the pipeline, the solenoid valve MV2 and the sampling pump 2-20. The power gas circuit is used to provide the power source for the normal temperature conveying sampling gas circuit and the heat conveying sampling gas circuit.

[0035] The normal temperature transport sampling gas circuit and the heat transport sampling gas circuit are respectively connected through the pipeline and the solenoid valve MV3, the vacuum gauge VG, and the vacuum pump 2-21 to form a vacuum air circuit. The vacuum air circuit is used to self-clean the gas circuit system and regenerate the adsorption material of the adsorption sampling module in combination with the purge gas circuit to ensure that the collected VOCS value is true and effective, and provide accurate samples for later laboratory analysis.

[0036] The dryer is used to filter the moisture in the sampled air and improve the adsorption performance of the adsorption sampling module. It has built-in color-changing silica gel 2-111, such as blue or light blue glass-like granular silica gel. After absorbing moisture, its color changes from blue to pink, prompting the operation and maintenance personnel to replace it, ensuring that the sampled gas enters the subsequent adsorption sampling module after drying.

[0037] 1~4# adsorption sampling modules 2-15, 2-16, 2-17, 2-18, are collected in groups of four and are used to enrich VOC in areas with dense cable laying S After the collection is completed, the collection area information is marked and placed in the collection box for later laboratory analysis.

[0038] Adsorption sampling module 2-15 has built-in activated carbon adsorption chamber 2-153, molecular sieve adsorption chamber 2-154, clay adsorption chamber 2-155, metal organic framework material adsorption chamber 2-156, and polymer adsorption resin adsorption chamber 2-157. Adsorption sampling modules 2 to 3# are selected and arranged in variable temperature chamber 2-14 to further enhance the comprehensive collection of wide boiling point VOCs under complex temperature and humidity environments in winter and summer.

[0039] Sealing joints are provided on both sides of the adsorption sampling module. The use requirements in the present invention are stringent, and a pin-type self-sealing joint is selected. It is immersed at a certain depth between the tongue-shaped part 2-152 and the groove-shaped part 2-151 without any intermediate seals, ensuring that the transport vibration pipeline system is permanently fastened from vacuum and pressure under high static and dynamic alternating gravity, so that the sampling gas is not contaminated during the transportation process and affects the accuracy of inspection and analysis.

[0040] The sampling bracket 2-23 includes an adjusting rod 2-231, a fixed rod 2-235, a movable rod sleeve fixing bolt 2-232, a movable rod sleeve 2-233, and an adjusting rod fixing bolt 2-234. The adjusting rod 2-231 is built into the fixed rod 2-235 and can be freely extended and retracted. The extended position is locked by the adjusting rod fixing bolt 2-234. Mobile rod sleeves 2-233 of different calibers are inserted into the outside of the adjusting rod 2-231 and the fixed rod 2-235 and can be freely raised and lowered. The extended position is locked by the mobile rod sleeve fixing bolt 2-232. The sampling connector 2-24 is respectively fixed on the top of the adjusting rod and each movable rod sleeve, and is connected to the sampling assembly through a conveying hose.

[0041] The delivery hose includes a PTFE normal temperature sampling tube 2-25 and a heating temperature-matching sampling tube 2-26. Both sides of the sampling tube are sealed and connected to the sampling joint and 1~4# quick joints respectively. The temperature-matching sampling tube 2-26 is electrically connected to the control system through a cable.

[0042] The temperature-variable module includes a cold and heat source supply module 2-13 and a temperature-variable bin 2-14. The cold and heat source supply module 2-13 is used to provide cold and heat to the temperature-variable bin 2-14. The temperature-variable bin 2-14 is a C-shaped opening and closing structure, which is insulatedly connected to the 2~3# adsorption sampling modules. The cold and heat source supply module 2-13 is electrically connected to the control system via a cable.

[0043] The disturbance component is a mature product on the market, such as a blower, and is electrically connected to the control system through a cable.

[0044] Application Examples

[0045] 1. Sampling joint arrangement

[0046] Cable trench: Press the sampling connector into Figure 5As shown, it is installed on the sampling bracket. The position of the sampling connector is adjusted by the laying height of the cable bracket. Samples are collected at each fire interval. The disturbance component is placed at the fire separation, and the sampling connector is placed in the middle of the fire separation section or at another fire separation section to realize VOCs collection in the fire separation section of the cable trench.

[0047] Cable tunnel or switch cabinet room: Press the sampling connector into Figure 5 As shown, it is installed on the sampling bracket. The position of the sampling connector is adjusted by the laying height of the cable bracket. It is arranged near the ventilation hole to realize VOCs collection in the cable tunnel or switch cabinet room.

[0048] Cable shaft: Place the sampling connector in the upper middle part of each fire compartment and place the disturbance component in the lower part of the fire compartment to collect VOCs in the cable shaft.

[0049] 2. VOC in areas with dense cable laying S Collection process

[0050] Preparation: Connect both sides of the delivery hose to the sampling connector and the gas system respectively, connect the adsorption sampling modules 1 to 4 to the sampling assembly, adjust the manual two-position three-way valves S1 and S2 to the appropriate position, and confirm that the manual ball valves V1 to V6 are in the closed state.

[0051] Purging: Open the manual ball valve V5, slowly open the nitrogen cylinder valve, adjust the pressure of the pressure reducing valve to 0.02MPa, and open the solenoid valve MV1 of the system. At this time, purge the normal temperature transport sampling system. After 5 minutes, open the manual ball valve V6 and close the manual ball valve V5. At this time, purge the heat transport sampling system. After 5 minutes, close the nitrogen cylinder valve and the pressure reducing valve, and the system closes the solenoid valve MV1 and the manual ball valve V6.

[0052] Vacuum self-cleaning: adjust the manual two-position three-way valves S1 and S2 to the appropriate position, open the manual ball valves V5 and V6, then turn on the solenoid valve MV3 and the vacuum pump. At this time, the normal temperature conveying sampling system and the heating conveying sampling system are evacuated for self-cleaning. When the vacuum gauge VG reaches the threshold, it prompts to close the manual ball valves V5 and V6. After confirming that the manual ball valves V5 and V6 are closed, the system closes the solenoid valve MV3 and the vacuum pump.

[0053] Sampling: The control system turns on the heating pipe and the temperature-changing module. When the threshold temperature is reached, it prompts to open the manual ball valves V1, V2, V3, V4, V5, and V6. After confirming that the manual ball valves V1, V2, V3, V4, V5, and V6 are open, the system turns on the sampling pump and the solenoid valve MV2 to collect VOCS in the cable-intensive laying area. The timing starts at this moment. After 1 hour, the system prompts that the VOCS collection is completed. After confirming that V1, V2, V3, V4, V5, and V6 are closed, the system turns off the sampling pump and the solenoid valve MV2. Take out the 1~4# adsorption sampling modules, label them, and put them in the toolbox. Then connect the four adsorption sampling modules to the sampling assembly, and repeat the above steps until the collection is completed.

[0054] 3. Laboratory Analysis

[0055] The adsorption sampling module with completed collection is placed in the variable temperature chamber and one end of the adsorption sampling module is connected to the laboratory analysis instrument through a pipeline. When the temperature of the variable temperature chamber reaches the threshold, laboratory testing and analysis are carried out to warn of possible faults of power combustibles such as cable sheaths, reduce fire hazards in densely laid cable areas of substations, and improve the work efficiency of front-line operation and maintenance inspection personnel.

[0056] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A VOC for densely laid cable areas in substations S The acquisition system is characterized in that include: Used to collect VOC in areas with dense cable laying S A sampling component, a disturbance component for forcing air disturbance in a densely laid cable area, and a control system. The sampling assembly includes an air path system, a sampling bracket, a sampling joint, a delivery hose, and a temperature-variable module. The sampling bracket is arranged in a cable-intensively laid area. A plurality of sampling joints are arranged on the sampling bracket to perform layered sampling in the cable-intensively laid area. The sampling joints are each connected to the air path system through a delivery hose. The air path system includes two sampling air paths, a power air path connected to the two sampling air paths, a purge air path, and a vacuum air path. The power air path, the purge air path, and the vacuum air path are arranged in parallel. The two sampling air paths include a normal-temperature delivery sampling air path and a heat-tracing delivery sampling air path. Each sampling air path includes two adsorption sampling modules arranged in parallel. The temperature-changing module includes a temperature-changing chamber and a cold and hot source supply device for selectively providing a cold source and a hot source to the temperature-changing chamber. The adsorption sampling module with one normal temperature delivery sampling gas path and one normal temperature delivery sampling gas path is placed in the temperature-changing chamber to realize refrigeration adsorption of VOC. S After the collection, the adsorption sampling modules of the four sampling gas paths are placed in the variable temperature chamber to achieve VOC S Heating desorption.

2. The VOC cable densely laid area for substation according to claim 1 S The acquisition system is characterized in that The conveying hose used in the conventional conveying and sampling gas circuit is a polytetrafluoroethylene normal temperature sampling tube, and the conveying hose used in the heating conveying and sampling gas circuit is a heating and temperature sampling tube.

3. The VOC cable densely laid area for substation according to claim 1 S The acquisition system is characterized in that The densely laid area for substation cables is cable trenches, cable tunnels and cable shafts.

4. The VOC cable densely laid area for substation according to claim 1 S The acquisition system is characterized in that The sampling bracket includes an adjusting rod, a fixed rod, a movable rod sleeve, a movable rod sleeve fixing bolt, and an adjusting rod fixing bolt. The adjusting rod is built into the fixed rod, and the telescopic position is locked by adjusting the adjusting fixing bolt. The movable rod sleeves are respectively inserted into the outside of the adjusting rod and the fixed rod, and can be freely raised and lowered. The telescopic position is locked by the movable rod sleeve fixing bolt. The sampling joints are respectively fixed on the top of the adjusting rod and each movable rod sleeve.

5. The VOC cable densely laid area for substation according to claim 1 S The acquisition system is characterized in that The adsorption sampling module is sequentially equipped with an activated carbon adsorption chamber, a molecular sieve adsorption chamber, a clay adsorption chamber, a metal organic framework material adsorption chamber, and a polymer adsorption resin adsorption chamber from inlet to outlet.

6. The VOC cable densely laid area for substation according to claim 1 S The acquisition system is characterized in that The normal temperature transport sampling gas circuit includes a sampling gas circuit branch, a 1# combiner, a quick connector connected to the 1# combiner in sequence, a 1# dust filter, a manual two-position three-way valve S1, a 1# dryer, 1# to 2# sampling gas circuit branches, and a manual ball valve, wherein the sampling gas circuit branches are at least two, both connected to the 1# combiner, the sampling gas circuit branches are provided with a quick connector and a manual ball valve connected to the transport hose, and the sampling gas circuit branches are provided with a quick sealing connector, an adsorption sampling module, and a quick sealing connector in sequence.

7. The VOC cable densely laid area for substation according to claim 6 S The acquisition system is characterized in that The heated conveying sampling gas circuit includes a sampling gas circuit branch, a 2# combiner, a quick connector connected to the 2# combiner in sequence, a 2# dust filter, a manual two-position three-way valve S2, a 2# dryer, a 3-4# sampling gas circuit branch, and a manual ball valve, wherein the sampling gas circuit branch is at least two-way, both connected to the 2# combiner, the sampling gas circuit branch is provided with a quick connector and a manual ball valve connected to the conveying hose, and the sampling gas circuit branch is provided with a quick sealing connector, an adsorption sampling module, and a quick sealing connector in sequence.

8. The VOC cable densely laid area for substation according to claim 7 S The acquisition system is characterized in that The collection methods include: Preparation steps: Connect both sides of the delivery hose to the sampling connector and the gas system respectively, connect all adsorption sampling modules to the sampling assembly, adjust the manual two-position three-way valve to the first position, and confirm that all manual ball valves V1 to V6 are closed; Purging step: Use the purge gas line to purge the normal temperature transport sampling gas line and the heat transport sampling gas line with nitrogen in turn, and end after reaching the set purge time; Vacuum self-cleaning step: use the vacuum air path to evacuate the normal temperature transport sampling air path and the heat transport sampling air path, and end when the vacuum degree reaches the threshold; Sampling steps: turn on the heating temperature-tracing pipe and the temperature-variable module, turn on the sampling power gas circuit when the set threshold is reached, control the sampling gas circuit to collect VOCS, and end after the set time is reached. Label all adsorption sampling modules and place them in the tool box, then connect the prepared adsorption sampling module to the sampling assembly, and continue sampling until the collection is completed; Analysis steps: Place all adsorption sampling modules that have been collected into a variable temperature chamber and connect one end of the adsorption sampling module to the analysis instrument through a pipeline. When the variable temperature chamber is heated to a threshold, perform laboratory analysis.

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