An online carrier gas switching device for an analyzer

Abstract

This application discloses an online carrier gas switching device for an analyzer, comprising an analytical instrument, a switching valve, and at least two gas supply lines. The outlet of the switching valve is connected to the analytical instrument. Each gas supply line is connected to the switching valve, and the switching valve selectively connects one of the supply lines to the analytical instrument. Each gas supply line includes a gas source, a first connecting pipe, and a pressure reducing valve. The gas source is connected to the inlet of the switching valve through the first connecting pipe, and the pressure reducing valve is installed on the first connecting pipe. The online carrier gas switching device for an analyzer disclosed in this application has at least two gas supply lines, one of which is connected to the analytical instrument via a switching valve. When the gas source of one supply line is depleted, the analyzer can be switched directly to another supply line with gas without stopping the analyzer, ensuring a continuous supply of carrier gas. The analyzer does not need to interrupt its operation due to carrier gas replacement, and can continuously analyze and detect the sample gas, obtaining continuous and accurate analytical data, thus avoiding interference with air separation operations.

Description

Technical Field

[0001] This application belongs to the technical field of analyzer supporting equipment, specifically relating to an online carrier gas switching device for analyzers. Background Technology

[0002] Air separation oxygen generators are equipped with numerous chromatographic analyzers. These analyzers work by using a carrier gas to carry the sample gas to be analyzed into a chromatographic column. Within the column, based on the differences in the partition coefficients of the different components in the sample gas, the components are separated and then carried to a detector for measurement, converting the result into standard concentration units. Therefore, the carrier gas and the pretreatment section, including the chromatographic column, play a crucial role in the analyzer.

[0003] The hydrocarbon analysis table for the main air separation unit and the neon content analysis table for the neon-helium column require pure nitrogen as the carrier gas during operation. Under normal operating conditions, the carrier gas must continuously flow through the chromatographic column; any interruption of the gas supply will cause the column to burn out, rendering it unusable. Furthermore, the analytical data has a significant impact on the air separation system.

[0004] However, when the nitrogen carrier gas runs out and the nitrogen cylinder needs to be replaced, the analyzer must be shut down. During this period, there is a possibility of excessive hydrocarbon levels in the main coolant, which could lead to a significant risk of explosion in the air separation tower and seriously affect the safe and stable operation of the air separation oxygen generator unit. Utility Model Content

[0005] To solve the above-mentioned technical problems, this application discloses an online carrier gas switching device for an analyzer.

[0006] This utility model provides an online carrier gas switching device for an analyzer, comprising: an analyzer; a switching valve, the outlet of which is connected to the analyzer; at least two gas supply lines, each of which is connected to the switching valve, wherein the switching valve selectively connects one of the gas supply lines to the analyzer, each gas supply line comprising a gas source, a first connecting pipe, and a pressure reducing valve, wherein the gas source is connected to the inlet of the switching valve through the first connecting pipe, and the pressure reducing valve is installed on the first connecting pipe.

[0007] According to one embodiment of the present invention, the gas supply line further includes a discharge valve, which is installed on the first connecting pipe and is located between the pressure reducing valve and the switching valve.

[0008] According to one embodiment of the present invention, the gas supply line further includes an extension pipe, which is connected to the first connecting pipe. The extension pipe is located between the pressure reducing valve and the switching valve, and the discharge valve is installed on the extension pipe.

[0009] According to one embodiment of the present invention, the gas supply line further includes a pressure gauge for detecting the pressure of the first connecting pipe, the pressure gauge being located between the pressure reducing valve and the switching valve.

[0010] According to one embodiment of the present invention, the gas supply lines are configured as two lines, which are respectively located on both sides of the analytical instrument.

[0011] According to one embodiment of the present invention, it further includes a second connecting pipe and an inflation valve for controlling the opening and closing of the second connecting pipe. The two ends of the second connecting pipe are respectively connected to two first connecting pipes, and the inflation valve is installed on the second connecting pipe.

[0012] According to one embodiment of the present invention, the second connecting pipe is connected to the first connecting pipe at a position between the gas source and the pressure reducing valve.

[0013] According to one embodiment of the present invention, the switching valve is a linkage-based disturbance-free switching valve.

[0014] According to one embodiment of the present invention, it further includes a rotor flowmeter, wherein the outlet of the switching valve is connected to the inlet of the rotor flowmeter, and the outlet of the rotor flowmeter is connected to the inlet of the analytical instrument.

[0015] According to one embodiment of the present invention, a back plate is also included, on which the analytical instrument, the rotor flow meter, the switching valve and each of the gas supply lines are installed.

[0016] As can be seen from the above technical solution, the online carrier gas switching device for the analyzer disclosed in this application includes an analyzer, a switching valve, and at least two gas supply lines. The outlet of the switching valve is connected to the analyzer. Each gas supply line is connected to the switching valve, and the switching valve selectively connects one line to the analyzer. The gas supply line includes a gas source, a first connecting pipe, and a pressure reducing valve. The gas source is connected to the inlet of the switching valve through the first connecting pipe, and the pressure reducing valve is installed on the first connecting pipe.

[0017] The online carrier gas switching device disclosed in this application has at least two gas supply lines, one of which is connected to the analytical instrument via a switching valve. When the gas supply from one of the supply lines runs out, the analyzer can be switched directly to the other supply line with available gas without stopping the analyzer, ensuring a continuous supply of carrier gas. This effectively avoids the problem of excessive hydrocarbon levels in the main coolant caused by downtime for gas source replacement, greatly reduces the risk of air separation tower explosion, and significantly improves the safety and stability of the air separation oxygen generator unit. The analyzer does not need to interrupt its operation due to carrier gas replacement and can continuously analyze and detect the sample gas to obtain continuous and accurate analytical data. Attached Figure Description

[0018] To enable those skilled in the art to more clearly understand this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0019] Figure 1 This is a schematic diagram of the online carrier gas switching device for the analyzer in one or more embodiments of this application; Figure 2 This is a schematic diagram of the online carrier gas switching device for the analyzer in another embodiment of this application.

[0020] Explanation of reference numerals in the attached drawings: 100, analytical instrument; 200, switching valve; 300, gas supply line; 310, gas source; 320, first connecting pipe; 330, pressure reducing valve; 340, discharge valve; 350, extension pipe; 360, pressure gauge; 400, rotor flow meter; 500, back plate; 600, second connecting pipe; 700, air charging valve. Detailed Implementation

[0021] To enable those skilled in the art to more clearly understand this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] Furthermore, reference numerals and / or reference letters may be repeated in different examples in this application. Such repetition is for simplification and clarity purposes and does not in itself indicate a relationship between the various embodiments and / or settings discussed. In addition, this application provides examples of various specific processes and materials; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0024] This utility model discloses an online carrier gas switching device for an analyzer, which can solve the technical problem that the analyzer needs to be shut down when changing nitrogen cylinders in the prior art. This avoids the risk of excessive hydrocarbon emissions in the main cooler and explosion of the air separation tower, realizes online carrier gas switching, ensures continuous operation of the analyzer, and improves the safety and stability of the air separation oxygen generator unit.

[0025] The technical solution of this application will be described in detail below through specific embodiments: See Figure 1 and Figure 2 This application discloses an online carrier gas switching device for an analyzer, which includes an analyzer 100, a switching valve 200, and at least two gas supply lines 300. The outlet of the switching valve 200 is connected to the analyzer 100. Each gas supply line 300 is connected to the switching valve 200, and the switching valve 200 selectively connects to one of the gas supply lines of the analyzer 100. Each gas supply line 300 includes a gas source 310, a first connecting pipe 320, and a pressure reducing valve 330. The gas source 310 is connected to the inlet of the switching valve 200 through the first connecting pipe 320, and the pressure reducing valve 330 is installed on the first connecting pipe 320.

[0026] The online carrier gas switching device disclosed in this embodiment has at least two gas supply lines 300, one of which is connected to the analyzer 100 via a switching valve 200. When the gas source 310 of one of the gas supply lines 300 is depleted, the analyzer can be switched directly to the other gas supply line 300 without stopping the analyzer, ensuring a continuous supply of carrier gas. This effectively avoids the problem of excessive hydrocarbon levels in the main coolant due to downtime for changing the gas source 310, greatly reduces the risk of air separation tower explosion, and significantly improves the safety and stability of the air separation oxygen generator unit. The analyzer does not need to interrupt its operation due to carrier gas changes and can continuously analyze and detect the sample gas to obtain continuous and accurate analytical data.

[0027] A pressure reducing valve 330 is installed on the first connecting pipe 320 of each gas supply line 300 to regulate the gas pressure output from the gas source 310 and stabilize it within the operating pressure range required by the analyzer 100. This ensures a stable carrier gas pressure entering the analyzer 100 and avoids damage to the analyzer 100 and its components such as the chromatographic column due to excessively high or low pressure.

[0028] The combined design of multiple gas supply lines 300 and switching valves 200 increases system redundancy. When one gas supply line 300 fails (such as a leak in the gas source 310 or damage to the pressure reducing valve 330), it can be switched to other normal lines in a timely manner, ensuring the normal operation of the analyzer. This redundancy design improves the reliability of the entire analyzer carrier gas supply system and reduces the possibility of system failure due to a single component failure.

[0029] In one embodiment, the gas supply line 300 further includes a discharge valve 340, which is installed on the first connecting pipe 320 and is located between the pressure reducing valve 330 and the switching valve 200.

[0030] When components such as switching valve 200 and analytical instrument 100 need to be repaired or replaced, there may still be carrier gas with a certain pressure in the system. At this time, opening the discharge valve 340 can safely release the carrier gas located between the pressure reducing valve 330 and the switching valve 200 in the first connecting pipe 320, so that the pressure in the pipeline can be quickly reduced to a safe range, avoiding safety accidents caused by high-pressure gas ejection when disassembling components, and ensuring the personal safety of operators.

[0031] When the gas source 310 needs to be replaced or a carrier gas of different properties needs to be switched, if there is residual gas in the pipeline, it may mix with the newly introduced gas, affecting the purity and quality of the carrier gas, and thus affecting the detection accuracy of the analyzer 100. Releasing the residual gas in the pipeline through the vent valve 340 can effectively prevent the mixing of different gases and ensure that the carrier gas entering the analyzer 100 each time is pure.

[0032] In one embodiment, the gas supply line 300 further includes an extension pipe 350. The extension pipe 350 is connected to the first connecting pipe 320 and is located between the pressure reducing valve 330 and the switching valve 200. The discharge valve 340 is installed on the extension pipe 350.

[0033] The presence of the extension pipe 350 increases the layout flexibility of the gas supply line 300. In actual installation scenarios, due to factors such as equipment space constraints and pipeline routing requirements, the length and routing of the first connecting pipe 320 may not meet the optimal installation needs. The extension pipe 350 can be customized and installed according to actual conditions, allowing the entire gas supply line 300 to be arranged more rationally, adapting to different working environments and equipment layouts, and improving the versatility and adaptability of the device.

[0034] In one embodiment, the gas supply line 300 further includes a pressure gauge 360 ​​for detecting the pressure of the first connecting pipe 320, the pressure gauge 360 ​​being located between the pressure reducing valve 330 and the switching valve 200.

[0035] The analyzer has specific requirements for carrier gas pressure; appropriate pressure is fundamental to ensuring accurate analytical results. Pressure gauge 360 ​​can display the carrier gas pressure value in the first connecting tube 320 in real time and with high precision, allowing operators to promptly understand the carrier gas pressure status. For example, in chromatographic analysis, fluctuations in carrier gas pressure can affect the separation of components and the response of the detector. Monitoring the pressure through pressure gauge 360 ​​ensures that the carrier gas pressure remains stable within the optimal range required by the analyzer, thereby obtaining accurate and reliable analytical data.

[0036] The pressure reducing valve 330 is used to regulate the carrier gas pressure, but relying solely on the adjustment of the pressure reducing valve 330 itself may not be able to accurately achieve the ideal pressure. The pressure gauge 360 ​​allows the operator to visually observe pressure changes and make fine adjustments to the pressure reducing valve 330 based on the data displayed by the pressure gauge 360, quickly adjusting the carrier gas pressure to the appropriate level and improving the efficiency and accuracy of pressure regulation.

[0037] In one embodiment, there are two gas supply lines 300, which are located on both sides of the analyzer 100.

[0038] Two independent gas supply lines 300 serve as backups for each other. If one line fails, such as when the gas source 310 runs out, a pipeline leak occurs, or a valve is damaged, the system can immediately switch to the other working line to continue supplying gas to the analyzer 100. This redundancy design greatly improves the stability of the carrier gas supply, ensuring that the analyzer 100 can operate uninterruptedly and avoiding analysis interruptions due to a single line failure.

[0039] Two gas supply lines 300 are located on both sides of the analyzer 100. When operators need to switch lines, they do not need to search for the switching position in the complex pipeline layout. They can quickly and intuitively find the switching valve 200 and operate it.

[0040] In one embodiment, the analyzer carrier gas online switching device further includes a second connecting pipe 600 and an inflation valve 700 for controlling the opening and closing of the second connecting pipe 600. The two ends of the second connecting pipe 600 are respectively connected to two first connecting pipes 320, and the inflation valve 700 is installed on the second connecting pipe 600.

[0041] In practical applications, situations may arise where a low-pressure gas source 310 cannot directly meet the analyzer's carrier gas pressure requirements. The second connecting pipe 600 and the charging valve 700 provide an effective solution. By controlling the opening and closing of the second connecting pipe 600 through the charging valve 700, the low-pressure gas source 310 can be charged, increasing its pressure to the appropriate range required by the analyzer. This expands the range of usable gas sources 310 and improves the device's adaptability to different gas sources 310. The gas source 310 being charged and the charging gas source 310 can use the same gas, or the charging gas source 310 can be an inert gas such as nitrogen.

[0042] Different analytical projects may require different types or purities of gas as carrier gas. The different gas supply lines 300 in this device can provide different gases, and the combination of the second connecting pipe 600 and the charging valve 700 makes switching between different gas sources 310 more flexible and convenient. When it is necessary to change the type of carrier gas, the gas can be quickly switched simply by controlling the charging valve 700 and switching the corresponding gas supply line 300, without complicated operations or additional equipment, thus meeting diverse analytical needs.

[0043] In certain specialized analytical applications, it may be necessary to use a mixed gas as a carrier gas. By properly controlling the second connecting pipe 600 and the charging valve 700, gases from different gas supply lines 300 can be mixed in a specific ratio before being supplied to the analyzer. This method of gas mixing and supply enables some special analytical methods.

[0044] In one embodiment, the second connecting pipe 600 is connected to the first connecting pipe 320 at a location between the gas source 310 and the pressure reducing valve 330.

[0045] When there is a pressure difference between the two gas supply lines 300, the carrier gas from the high-pressure line can be directed to the low-pressure line by controlling the opening and closing of the gas charging valve 700. Since the carrier gas has not yet been regulated by the pressure reducing valve 330, its pressure is relatively high and varies widely. This connection method can more effectively balance the initial pressure of the two lines.

[0046] If the pressure imbalance between the two lines is regulated after the pressure reducing valve 330, the valve will need to be frequently adjusted to adapt to different pressure inputs. This increases the workload of the pressure reducing valve 330, accelerating its wear and aging. Connecting the second connecting pipe 600 between the air source 310 and the pressure reducing valve 330 allows for preliminary pressure balancing, making the pressure received by the pressure reducing valve 330 more stable and consistent. This reduces the burden on the pressure reducing valve 330, extends its service life, and lowers the equipment failure rate.

[0047] In one embodiment, the switching valve 200 is a linkage-free switching valve 200.

[0048] During carrier gas switching, a conventional switching valve 200 may experience significant instantaneous changes in carrier gas flow rate due to mechanical structure or switching method issues. However, the linkage-based non-disruptive switching valve 200, through its unique linkage mechanism design, achieves smooth and gradual valve switching. This switching method keeps the carrier gas flow rate relatively stable during the switching process, avoiding interference to the analyzer's detection signal caused by sudden flow changes.

[0049] In one embodiment, the analyzer carrier gas online switching device further includes a rotor flow meter 400. The outlet of the switching valve 200 is connected to the inlet of the rotor flow meter 400, and the outlet of the rotor flow meter 400 is connected to the inlet of the analyzer instrument 100.

[0050] The rotor flowmeter 400 is an instrument that intuitively displays fluid flow rate. The position of its internal rotor rises and falls with changes in carrier gas flow rate, and the current carrier gas flow rate can be directly read through the dial. This allows operators to monitor the carrier gas flow rate entering the analyzer 100 in real time and accurately, without the need for complex instruments or calculation methods, greatly facilitating carrier gas flow monitoring.

[0051] According to the requirements of the analytical instrument 100, the carrier gas flow rate needs to be precisely controlled to ensure the accuracy and repeatability of the analytical results. The rotor flow meter 400 can precisely change the carrier gas flow rate by adjusting the opening of its inlet or outlet valve. The operator can precisely adjust the carrier gas flow rate to the required value according to the scale indication on the flow meter to meet the stringent requirements of different analytical projects on carrier gas flow rate.

[0052] In one embodiment, the analyzer carrier gas online switching device further includes a backplate 500. The analyzer instrument 100, the rotor flowmeter 400, the switching valve 200, and each gas supply line 300 are all mounted on the backplate 500.

[0053] The back panel 500 provides a centralized mounting platform for all components, allowing the analytical instrument 100, rotor flow meter 400, switching valve 200, and gas supply line 300 to be arranged and fixed in an orderly manner. This compact layout greatly reduces the space occupied by the components, making it particularly suitable for situations with limited space in laboratories or industrial sites. It enables the integration of more equipment and functions within a limited space, improving space utilization.

[0054] By pre-designing and planning on the back panel 500, the positions of each component can be rationally arranged according to its function and frequency of use. For example, frequently operated and observed analytical instruments 100 and rotor flowmeters 400 can be installed in easily accessible locations, while less frequently operated components such as switching valves 200 and gas supply lines 300 can be installed in suitable locations, making the overall spatial layout of the device more rational and efficient.

[0055] Through the above embodiments, this application has the following beneficial effects or advantages: The online carrier gas switching device for the analyzer disclosed in this application, by setting at least two gas supply lines 300 and a switching valve 200, allows the analyzer to switch directly to another gas supply line 300 without stopping the analyzer's operation when the gas source 310 of one gas supply line 300 is exhausted. This ensures a continuous supply of carrier gas, avoids the risk of excessive hydrocarbon emissions in the main coolant and explosion of the air separation tower due to shutdown, and greatly improves the safety and stability of the air separation oxygen generator unit. The pressure gauge 360 ​​can monitor the pressure in the gas supply line 300 in real time, and the operator can adjust the pressure reducing valve 330 in a timely manner according to the pressure situation. At the same time, the combined use of the second connecting pipe 600 and the charging valve 700 can balance the pressure between the two lines when switching gas supply lines 300, reduce pressure fluctuations during the switching process, protect the analyzer instrument 100 and the chromatographic column, and ensure the accuracy of the analytical data. The exhaust valve 340 is designed to facilitate the discharge of residual gas in the gas supply line 300. When maintaining or replacing the gas source 310, the gas in the pipeline can be quickly emptied, improving operating efficiency and reducing maintenance time.

[0056] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model have been clearly and completely described above with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0057] Therefore, the above detailed description of the embodiments of the present invention disclosed in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0058] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0059] In the description of this utility model, it should be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0060] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0061] In this invention, unless otherwise expressly specified and limited, "above or below" the first feature may include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on" the first feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the first feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0062] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0063] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. An analytical instrument carrier gas on-line switching device, characterized by, include: Analytical instruments; A switching valve, the outlet of which is connected to the analytical instrument; At least two gas supply lines are provided, each of which is connected to the switching valve. The switching valve selects one of the lines to connect to the analytical instrument. Each gas supply line includes a gas source, a first connecting pipe, and a pressure reducing valve. The gas source is connected to the inlet of the switching valve through the first connecting pipe, and the pressure reducing valve is installed on the first connecting pipe.

2. An analyser carrier gas on-line switching device according to claim 1 characterised in that, The gas supply line also includes a discharge valve, which is installed on the first connecting pipe and is located between the pressure reducing valve and the switching valve.

3. An analyser carrier gas on-line switching device according to claim 2 characterised in that, The gas supply line also includes an extension pipe, which is connected to the first connecting pipe. The extension pipe is located between the pressure reducing valve and the switching valve, and the discharge valve is installed on the extension pipe.

4. The analyzer carrier gas on-line switching device of claim 1, wherein, The gas supply line also includes a pressure gauge for detecting the pressure of the first connecting pipe, the pressure gauge being located between the pressure reducing valve and the switching valve.

5. The analyzer carrier gas on-line switching device of claim 1, wherein, The gas supply lines are configured as two, and the two gas supply lines are located on both sides of the analytical instrument.

6. An analyser carrier gas on-line switching device according to claim 5, characterised in that, It also includes a second connecting pipe and an inflation valve for controlling the opening and closing of the second connecting pipe. The two ends of the second connecting pipe are respectively connected to the two first connecting pipes, and the inflation valve is installed on the second connecting pipe.

7. An analyser carrier gas on-line switching device according to claim 6, characterised in that, The second connecting pipe is connected to the first connecting pipe at a position between the gas source and the pressure reducing valve.

8. An analyser carrier gas on-line switching device according to any one of claims 1 to 7, characterised in that, The switching valve is a linkage-based, disturbance-free switching valve.

9. An analyser carrier gas on-line switching device according to any one of claims 1 to 7, characterised in that, It also includes a rotor flow meter, the outlet of the switching valve is connected to the inlet of the rotor flow meter, and the outlet of the rotor flow meter is connected to the inlet of the analytical instrument.

10. An analyser carrier gas on-line switching device according to claim 9, characterised in that, It also includes a backplate, on which the analytical instruments, the rotor flowmeter, the switching valve, and each of the gas supply lines are installed.

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