TW202028672A - Apparatus and method for thermal treatment of moving web strips - Google Patents

Abstract

The present invention relates a hot air circulating chamber with air-flow control system used in manufacture of thermo-plastic products such as monofilament, plastic web strips, narrow film strip, multi-filament. Conventional systems do not allow controlling temperature and air-flow in hot air channel/chamber to achieve uniformity. With the increased production speed and stringent product requirements, improved air-flow uniformity and temperature precision in the hot air oven is necessary. Invention discloses an apparatus (1) provided with air-flow path having provision of number of fans (7), optimisation of heater (6) location and increased number of air-flow regulators (8) having control levers (9). Moving web strips (5) enter apparatus into a hot air channel (4) formed between upper chamber (2) and lower chamber (3). Entry point of moving strips into the hot air channel (4) is the web-strip inlet (5A). After getting heat treated, the moving web strips (5) leave the apparatus through the web strip outlet (5B).

Description

Apparatus and method for heat treatment of moving mid-belly plates

The present invention relates to the manufacture of thermoplastic products such as monofilaments, plastic web tapes, narrow film tapes, and multifilaments. In particular, it relates to a hot air circulation chamber with an air flow control system.

Various thermoplastic objects with a very high aspect ratio during manufacture undergo heat treatment using known equipment such as hot plates or hot air ovens. These thermoplastic objects can take the form of monofilament, narrow web tape, multifilament and other plastic webs.

A typical device for heat treatment of moving webs is a conventional hot air oven (see Figure 1), which is composed of an upper chamber and a lower chamber, which are mutually connected by a hinge along one of its edges. even. Each chamber has an insulating body in which a fan with a desired scroll is installed. The airflow guide shell (not shown) forms the air inlet and outlet of each fan. A hot air channel (at the interface of the chamber) is formed on the closure of the two chambers. The hot air passage receives hot air from the chamber through the inlet port(s) provided at one end of the passage (air inlet end) in the chamber. The air from the hot air channel leaves the channel and re-enters the chamber through the air outlet port(s) provided in the chamber at the other end of the channel (the air outlet end). A series of heaters are installed on the air inlet housing path (not shown), and the fans are used to draw hot air with a desired temperature. The hot air blown by the fan is guided through the flow guide channel and an air flow control rod. The inflow of hot air at the intake section of the hot air oven is controlled by the individual baffle position.

As can be seen from the schematic diagram given for the conventional system, it is actually impossible to control the temperature and air flow in the hot air channel/chamber to achieve uniformity across the channel. In addition, it should be noted that, from the air inlet end to the air outlet end of the chamber, the air flow in the hot air channel is disturbed by the introduction of the endless web belt in the fast movement. It should also be noted that in the conventional oven, airflow control at multiple locations or temperature monitoring at various points of the hot air passage are not provided. Therefore, the air flow and temperature state through the hot air channel can be non-uniform and can adversely affect the quality of the stretched belt.

Hot air channels are provided to assist the stretching of a tape/strip made of thermoplastic material made into a woven fabric. During the stretching process, the group of web strips pass through the hot air channel in order to achieve the required mechanical properties of the stretch strip. With advances in the application field of the final product, there are stricter requirements for product uniformity across the width of the hot air passage and along the length of the final product. This usually translates to the need for better control of one of the program parameters during the manufacturing process.

In addition, as the production speed and strict requirements of the final product increase, there is a need for improvement in air flow uniformity and temperature accuracy in the hot air oven. Invention goal

The main purpose of the present invention is to provide an apparatus and method for heat treatment of a moving web strip so that the heat treatment is uniform throughout the hot air passage forming a part of the apparatus.

Another object of the present invention is to ensure that the width and length of the air flow across the hot air passage are uniform.

Another purpose is to use precision control to provide uniform temperature in the hot air passage.

A further objective is to provide the ability to independently control the air flow in the hot air in the chamber duct.

A further objective is to provide the ability to individually control the airflow in different parts of the hot air passage.

The present invention relates to a hot air circulation chamber with an air flow control system, which is used to manufacture thermoplastic products (for example, monofilament, plastic web tape, narrow film bag, multifilament). The conventional system does not allow to control the temperature and air flow in the hot air passage/chamber to achieve uniformity. With the increased production speed and strict product requirements, it is necessary to improve the uniformity of air flow and temperature accuracy in the hot air oven. The present invention discloses a device (1) with an air flow path, which provides a number of fans (7), heaters (6) to optimize the position and increase the number of air regulators (8), the regulators have control rods (9).

Moving the middle web strip (5) allows the equipment to enter a hot air channel (4) formed between the upper chamber (2) and the lower chamber (3). The entry point to the moving belt in the hot air passage (4) is the web belt entrance (5A). After the heat treatment, the moving web strip (5) leaves the device through the web strip outlet (5B).

As previously discussed, the conventional hot air oven as shown in FIG. 1 has an upper chamber and a lower chamber. In addition, each chamber has an insulating body in which a fan with a desired scroll is installed. The airflow guide shell (not shown) forms the air inlet and outlet of each fan. A series of heaters are installed on the air inlet housing path (not shown), and the fans are used to draw hot air with a desired temperature. The hot air blown by the fan is guided through the flow guide channel and an air flow control rod. The inflow of hot air at the intake section of the hot air oven is controlled by the individual baffle position.

As previously discussed, the conventional oven (see Figure 1 and Figure 1A) does not allow the general control of the temperature and air flow in the hot air passage. As we have also noticed, the air flow in the hot air passage from the air inlet end to the air outlet end of the chamber is disturbed by the introduction of the endless web belt which is moving fast. It should be noted that in the conventional oven, air flow control at multiple locations or temperature monitoring at various points of the hot air passage are not provided. Therefore, the air flow and temperature state through the hot air channel can be non-uniform and can adversely affect the quality of the stretched belt.

In order to solve the above-mentioned problems in the conventional hot air oven, the present invention discloses a device (1) (or hot air oven) for heat treatment of a moving web strip (5). As shown in Figure 2, the device (1) has an air flow path, which provides a number of fans (7), heaters (6) to optimize the position and increase the number of air regulators (8) or control points, which Equipped with rod (9). An air flow regulator has a mechanism such as a fin or a fin, the angle of which can be adjusted using a rod (9) to adjust the air flow through the regulator (8).

In one aspect of the invention, a single lever can control more than one regulator (8).

The moving middle web strip (5) allows the equipment to enter a hot air channel (4) formed between an upper chamber and a lower chamber. The entry point to the moving chamber in the hot air channel (4) is the web strip entrance (5A). After the heat treatment, the moving web strip (5) leaves the device through the web strip outlet (5B).

As shown in Figure 3, such as a preferred embodiment of the present invention, thermal equipment, the upper chamber (2) and the lower chamber (3) are further divided into multiple ducts (2a and 3a), which depends on the hot air The overall working width of the oven (1). The upper chamber and the lower chamber can be divided into multiple ducts. At least one fan (7) and heater (6) group is arranged in each of the ducts (2a and 3a). However, the structures of the upper chamber (2) and the lower chamber (3) are similar and preferably but not necessarily have the same number of ducts (2a and 3a). Each duct is provided with an air blowing fan (7), a heater (6) group and a single air regulator (8) open to the hot air passage.

According to the present invention, each duct (2a and 3a) has a specially designed air flow path, which has an individual fan/blower (7) and a heater (6) group arranged adjacent to the blower impeller, thereby minimizing heat loss. In addition, the hot air from the upper chamber and the lower chamber (2, 3) exits the channel (4) through more than one air outlet (10), and the air outlet (10) is arranged in sequence along the length of the entrance area near the web of the device . Similarly, an air inlet (11) is provided at the end of the web strip outlet (5B) of each of the compartments (2, 3) to introduce circulating hot air from the channel back to the ducts (2a, 3a). In addition, each outlet (10) provided to send hot air from the chamber/duct to the hot air channel (4) has an individual flow regulator (8) with a rod (9), so as to meet the design requirements of the equipment Gives more controlled airflow.

In order to facilitate the opening of the hot air oven through the hot air channel (4), the upper chamber and the bottom chamber (2, 3) are connected on either longitudinal side by a hinge system preferably operated by a pneumatic mechanism for The group or individual of screw web belt (5). During the operation of the hot air oven, the upper chamber (2) descends above the bottom chamber (3) and forms a hot air channel (4). The hot air channel (4) is therefore closed or sealed on its side (in the direction of the moving belt (5)). The hot air passage (4) extends between the air outlet (10) and the air inlet (11) arranged at respective opposite ends of the hot air passage (4).

When the hot air introduced into the channel (4) travels through the length of the channel from the web strip inlet (5A) to the web strip outlet (5B), it loses heat and cools. Once the cold air is re-introduced from the channel (4) back to the chamber (2, 3), it is heated by the heater/fan blower unit. The hot air travels along the length of the chambers (2, 3) toward the entrance end (5A) of the web belt. At the entrance end (5A) of the web belt, the air is introduced into the channel ( 4) Medium. Therefore, the heating and cooling cycle of the air is continued.

The air outlet (10) is provided with more than one airflow regulator (8) for each duct (2a, 3a) or chamber (2, 3), by means of which the air outlet (10) port (set in the hot air The air flow from the air inlet end of the channel (4)) to the hot air channel (4). The air flow rod (9) can be adjusted by using at least one operating position, whereby the amount of air passing through the air flow regulator (8) can be adjusted. Through the adjustable positioning of the airflow rod (9) arranged in the airflow regulator (8), the required amount/rate of the airflow to the hot air passage (4) is controlled. The individual air regulator (8) has several position settings, which can be adjusted by the lever (9), which realizes the repeatability of the procedure.

In addition, since the heater(s) (6) in the ducts/chambers (2, 3) are arranged in the proximity of the corresponding fans (7), more precise temperature control is achieved. Multiple air ducts and multiple air flow regulators ensure equalized pressure and more uniform air flow in one of the hot air channels. The overall insulation of each chamber further ensures efficient energy utilization.

In a preferred embodiment of the present invention, a sensor (not shown) is provided for monitoring the temperature at each point of the hot air passage (4). The temperature and speed of the airflow passing through the outlet port (10) to the channel (4) depend on the denier and speed of the belt, and the final product demand. Since this can vary greatly depending on the needs of the end user, providing multiple air outlet ports (10) is an important feature of the present invention.

In another preferred embodiment, an air flu sensor (not shown) is provided for sensing and measuring the airflow velocity in the hot air channel. The position of the air flow regulator (8) is adjusted to control the air flow through the regulator (8) depending on the data obtained from the temperature and air flu detector.

The present invention also provides a method for heat-treating a moving web strip using the equipment disclosed herein. The method includes the following steps: adjusting the temperature of the air in the ducts (2a, 3a) of the chambers (2, 3) and the like depending on the known parameters such as the speed of Danny and the like traveling through the channel (4) and The speed is such that the air with the required temperature and speed is released from the chamber through the air outlet port (10) to the hot air channel (4).

It is understood from the above discussion that the present invention has several embodiments.

The preferred embodiment discloses a device for heat treatment of a moving web strip. The device includes an upper chamber (2) and a lower chamber (3), and a channel (4) is located between the two chambers for the future The hot air from the web belt inlet (5A) is carried to the web belt outlet (5B). During this stroke, the hot air cools down, and the web belt (5) travels in the longitudinal direction through the channel (4) during this stroke. ), characterized in that each of the chambers (2, 3) has at least one separate air outlet (10) and a separate air inlet (11), and the at least one air outlet will come from the chambers (2, The hot air of 3) is brought into the passage (4), and the air inlet (11) brings the cooled air after traveling through the passage (4) back to the chambers (2, 3), And wherein each of the air inlets (10) is provided with at least one individual airflow regulator (8) with an operating rod (9), and further wherein each of the chambers (2, 3) has a belt near the web At least one heater (6) and one fan (7) at the outlet (5B) heat the cold air for further circulation.

In one aspect of the invention, a single rod (9) can control more than one air regulator (8).

In another aspect of the present invention, the chambers (2, 3) are divided into individual ducts (2a, 3a).

In a further aspect of the present invention, each of the ducts (2a, 3a) has at least one heater (6), at least one fan (7), and at least one flow regulator with an operating lever (9) (8) Each of them.

In a further aspect of the present invention, the number of ducts (2a) in the upper chamber (2) and the number of ducts (3a) in the lower chamber (3) are the same.

In another aspect of the present invention, the fan (7) and the heater (6) are installed adjacent to each other.

In another aspect of the present invention, there may be more than one air outlet (10) for each of the chamber (2, 3) or the duct (2a, 3a).

In another aspect of the invention, the upper chamber (2) and the lower chamber (3) are connected by at least one hinge (12) on any longitudinal side of the device.

In a further aspect of the present invention, the operating rod (9) can be adjusted by using at least one operating position, whereby the velocity (or speed) of the air passing through the airflow regulator (8) can be adjusted.

In a further aspect of the present invention, the fan (7) and the heater (6) are positioned near the ends of the air inlets (11) of the chambers (2, 3).

In another aspect of the present invention, the channel (4) is equipped with temperature measuring and monitoring sensors. The channel (4) is also equipped with air velocity measurement and monitoring sensors.

In a further aspect of the present invention, the temperature and speed of the air released into the channel (4) are controlled based on the Danny and speed of the moving belt (5) and the demand for the final product.

In another aspect of the present invention, a method for processing a moving web strip (5) is disclosed, the method comprising the following steps: Provide equipment such as any one of technical solutions 1 to 12, and Heat the air to the desired temperature inside the chamber (2, 3) The control rod (9) is used to release the air flow from the chambers (2, 3) through the air flow regulators (8) into the channel (4) at a required speed.

The following examples illustrate the ways in which the invention is used. A belt of 1000 deniers or a film is passed through an oven made according to the present invention. The upper compartment of the oven includes two ducts and the lower compartment includes two ducts. The set temperature of the oven is 160 ^o C. The belt travels at a speed of 8 m/s. Use five individual air flow regulators in each duct to set the air flow rate to 10 to 11 m/s. The temperature of the belt is measured at randomly selected locations along the length of the oven at various locations across the width of the oven. It is found that the temperature change of the zone from the set temperature is between -0.25% and 1.88%. This is much lower than the 0.44% to 3.6% change experienced by using a conventional oven. This means that the temperature change is nearly 100% lower than that of the belt processed in a conventional oven.

Although the above description contains a lot of specificity, these should not be regarded as limiting the scope of the present invention, but as one of its preferred embodiments. It must be realized that modifications and changes based on the disclosure given above are possible without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should not be judged by the illustrated embodiments, but should be limited by the scope of the appended invention application patent and its legal equivalents.

1: Hot air oven 2: upper chamber 3: Lower chamber 4: Hot air channel 5: Web belt 5A: Web with entrance 5B: Web with exit 6: heater 7: Fan 8: Airflow regulator 9: lever/control lever 10: Air inlet 11: air outlet 12: Hinge

Figure 1 and Figure 1A show a conventional device for heat treatment of a moving web strip.

Figure 2 shows the device of the invention in a longitudinal view.

Figure 2A shows a cross-sectional view of the device of the present invention.

Fig. 3 shows a cross-sectional view of an embodiment of the apparatus of the present invention having a plurality of catheters in the upper chamber and the lower chamber.

1: Hot air oven

2: upper chamber

3: Lower chamber

4: Hot air channel

5: Web belt

5A: Web with entrance

5B: Web with exit

6: heater

7: Fan

8: Airflow regulator

10: Air inlet

11: air outlet

Claims (14)

A device for heat treatment of a moving web strip. The device includes an upper chamber (2) and a lower chamber (3), and a channel (4) is located between the two chambers to pass the web strip entrance ( The hot air of 5A) is carried to the web strip outlet (5B). During this stroke, the hot air cools down, and the web strip (5) travels in the longitudinal direction through the channel (4) during the movement, which is characterized by Each of the chambers (2, 3) has at least one separate air outlet (10) and a separate air inlet (11), the at least one air outlet will be the heat from the chambers (2, 3) The air is brought into the passage (4), and the air inlet (11) brings back the cooled air after traveling through the passage (4) to the chambers (2, 3), and the air inlets (11) Each of the air ports (10) has at least one individual airflow regulator (8) with an operating lever (9), and further wherein each of the chambers (2, 3) has an outlet (5B) close to the web At least one heater (6) and one fan (7) heat the cold air for further circulation. Such as the device of claim 1, wherein the chambers (2, 3) are divided into individual catheters (2a, 3a). Such as the device of claim 2, wherein each of the ducts (2a, 3a) has at least one heater (6), at least one fan (7) and at least one flow regulator (8) with an operating lever (9) ) Of each. Such as the device of claim 2 or 3, wherein the number of catheters (2a) in the upper chamber (2) and the number of catheters (3a) in the lower chamber (3) are the same. Such as the equipment of any one of claims 1 to 3, wherein the fan (7) and the heater (6) are installed adjacent to each other. Such as the device of any one of claims 1 to 3, wherein there may be more than one air outlet (10) for each of the chambers (2, 3) or ducts (2a, 3a). The device of any one of claims 1 to 3, wherein the upper chamber and the lower chamber (3) are connected by at least one hinge (12) on any longitudinal side of the device. Such as the equipment of any one of claims 1 to 3, wherein the operating rods (9) can be adjusted by using at least one operating position, whereby the amount of air passing through the airflow regulator (8) can be adjusted. Such as the equipment of any one of claims 1 to 3, wherein the fan (7) and the heater (6) are positioned near the end of the air inlet (11) of the chambers (2, 3). Such as the device of any one of claims 1 to 3, wherein the channel (4) is equipped with temperature measuring and monitoring sensors. Such as the equipment of any one of claims 1 to 3, wherein the channel (4) is equipped with air flow measurement and monitoring sensors. Such as the equipment of any one of claims 1 to 3, wherein the temperature and speed of the air released into the channel (4) are controlled based on the Danny and speed of the moving belt (5) and the demand for the final product. Such as the equipment of any one of claims 1 to 3, wherein any single lever (9) controls more than one air regulator (8). A method for processing a moving web belt (5), the method includes the following steps: Provide equipment as requested in any one of items 1 to 12, and Heat the air to the desired temperature inside the chamber (2, 3) The control rod (9) is used to release the air flow with the required speed from the chambers (2, 3) through the air flow regulators (8) into the channel (4).

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