A method of molding in place a quartz / phenolic tip with an embedded probe temperature sensor

Abstract

The application discloses a quartz / phenolic end head moulding method of an embedded probe temperature sensor, and steps are as follows: forming and processing of a probe temperature sensor protection support; packaging of the probe temperature sensor; forming of an end head product; and processing of the end head product. The application makes full use of the flexibility of the moulding process, the designability of the material, and the excellent ablation resistance of the quartz fiber and the phenolic resin, avoids the problem that cannot be operated due to the characteristics of the forming process, and reduces the preparation difficulty of the product. The quartz / phenolic composite material is used to replace the traditional conical metal piece, which greatly reduces the total mass of the end head. The product has high size precision, good internal quality, and low manufacturing cost after forming. In the case of meeting the normal use of the embedded probe type temperature sensor, the overall aerodynamic structure of the end head is not damaged. After the power and heat test, the material selection and design of the end head are obviously improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of preparation of aerospace load-bearing / heat-proof structural parts, and relates to a quartz / phenolic end head mold pressing forming method with an embedded probe temperature sensor. BACKGROUND

[0002] An extreme aerodynamic force, aerodynamic heat and other complex physical phenomena are generated during the flight of a certain product. The head of the product is rapidly rubbed by high-temperature airflow, and a large amount of heat is generated in a short time, which is transferred to the surface of the product to form a relatively high temperature in different areas. Under the action of high pressure and high overload, the structure of the end head part may be damaged or even disintegrated. If the end head is designed to be heat-proof, not only the manufacturing cost and the weight of the product are increased, but also the asymmetric ablation of the product is caused, resulting in unstable flight. Therefore, it is necessary to prepare an end head with high stability, high adaptability, low cost and capable of detecting the actual temperature change in the flight process, so as to provide a basis for the selection of the material of the end head and the design of the heat-proof structure for the subsequent flight product.

[0003] At present, the main materials used for the end head are resin-based, carbon-based and ceramic-based. Among them, the carbon-based heat-proof material is mainly carbon / carbon composite material, that is, carbon fiber woven fabric is deposited with carbon or impregnated with carbon through chemical vapor deposition (CVD), and then carbonized or graphitized to form. If the flight task is temporarily changed, the sublimation effect of the carbon-based material cannot be played, and it becomes a simple oxidation combustion, which cannot achieve the expected heat-proof effect. The ceramic-based heat-proof material is mainly carbon / quartz composite material, and the forming process is to melt the submicron level base particles in an inert gas atmosphere and then impregnate them on the preformed body of the reinforcing material. The process method has high requirements for equipment. These two preparation methods can only bond the temperature sensor in the end head through post-processing, which destroys the integrity of the end head and may cause the end head to explode and disintegrate under extreme flight conditions. The main component of high-silica fiber and quartz fiber in the resin-based material is silicon dioxide, and the latent heat of vaporization of silicon dioxide is 3000 kcal, which can further absorb aerodynamic heat. After melting at high temperature, a liquid film with high viscosity is formed, which is not easy to be washed away under high airflow. Phenolic resin is immediately carbonized to form a carbon atom skeleton layer with high heat resistance and high strength, which is not easy to be washed away. The combination of the two forms a carbonization-melting type ablation material, which can further radiate and block heat flow. At the same time, the mold pressing forming process has strong designability and operability. The traditional end head is directly mold pressed after sandblasting of the conical metal part. SUMMARY

[0004] (I) Invention purpose

[0005] The purpose of the application is to provide a quartz / phenolic end head mold pressing forming method with an embedded probe temperature sensor, which can not only meet the needs of flight products for load-bearing and heat-proof, but also collect real-time change data of the end head temperature during flight.

[0006] (II) Technical Solution

[0007] To solve the above technical problems, the application provides a method for molding an inlaid probe temperature sensor quartz / phenolic end piece, comprising the following steps:

[0008] (1) Molding and processing of the probe temperature sensor protection bracket: the bracket is divided into two parts, the center butt joint groove is used for arranging the sensor, and a positioning protrusion and a positioning groove are arranged on the butt joint surface; short fiber quartz / phenolic premix is prepared, the mold is loaded, the probe temperature sensor protection bracket preform blank is pressed, the probe temperature sensor protection bracket blank is processed, and a tapered probe temperature sensor protection bracket is obtained. The end of the bracket is provided with a protection rod for avoiding damage to the sensor during the closing of the press in step 3.

[0009] (2) Packaging of the probe temperature sensor: probe temperature sensor wiring, probe temperature sensor bonding, probe temperature sensor bracket assembly, probe temperature sensor on-off detection, probe temperature sensor bonding and packaging, probe temperature sensor bracket curing, processing into an irregular stepped groove, and obtaining a probe temperature sensor built-in part.

[0010] (3) Molding of the end piece: short fiber quartz / phenolic premix is prepared, the probe temperature sensor built-in part is placed into the end piece mold, the inner ring short fiber quartz / phenolic premix is filled in the end piece mold, preforming is performed, the probe temperature sensor on-off detection is performed, the outer ring long fiber quartz / phenolic premix of the end piece is filled, molding is performed, the probe temperature sensor is tested, and an inlaid probe temperature sensor quartz / phenolic end piece rough product is obtained. The end piece mold comprises an upper mold and a lower mold. The upper mold is used for fixing the probe temperature sensor built-in part and is an inverted character-shaped structure, the top plane of the upper mold is in contact with the press, the bottom surface is provided with a built-in part positioning groove, and the positioning pins for butt joint with the lower mold are arranged on the two side steps. The lower mold is a concave character-shaped structure, contains a mold cavity for forming the end piece, and the filling process is centered on the probe temperature sensor built-in part. The inner ring of the end piece is defined as surrounding the probe temperature sensor built-in part, and the outer ring of the end piece is defined as surrounding the inner surface of the lower mold cavity.

[0011] (4) Processing of the end piece: the inlaid probe temperature sensor quartz / phenolic end piece structure rough product is machined to remove the front part protection rod, the end product is placed in an oven for post-curing, and an inlaid probe temperature sensor quartz / phenolic end piece is obtained.

[0012] Further, the short fiber quartz of the short fiber quartz / phenolic in step (1) is a reinforcing material, and the quartz fiber tows are cut, and the length of the cut fibers is not more than 30 mm to 50 mm.

[0013] Further, the base material of the short fiber quartz / phenolic premix in step (1) is one or a mixture of several of the following: ammonia-phenolic resin, magnesium-phenolic resin, boron-phenolic resin.

[0014] Further preferably, the resin of the short fiber quartz / phenolic premix is magnesium-phenolic resin.

[0015] Further, in step (1), the short fiber quartz / phenolic premix is preheated in an oven, the preheating temperature is 80-90°C, and the preheating time is 20-30 minutes. The short fiber quartz / phenolic premix is evenly loaded into the mold cavity in two times.

[0016] Further, in step (1), the short fiber quartz / phenolic premix is preheated in an oven, the preheating temperature is 80-90°C, and the preheating time is 20-30 minutes. The short fiber quartz / phenolic premix is evenly loaded into the mold cavity in two times.

[0017] Further preferably, the closing of the mold is performed by closing the upper and lower molds on the hydraulic machine.

[0018] Further preferably, the preheating is performed by heating the mold temperature to 80-90°C from room temperature using an electric heating rod for 40-45 minutes.

[0019] Further preferably, the temperature maintenance is performed by maintaining the mold temperature at 80-90°C for 40-50 minutes.

[0020] Further preferably, the contact pressure is applied by using a hydraulic machine to apply a pressure of 1-2 MPa during the temperature maintenance for 20-25 minutes.

[0021] Further preferably, the temperature increase is performed by increasing the mold temperature to 120-130°C at a rate of 2-5°C per 10 minutes.

[0022] Further preferably, the pressure increase is performed by using a hydraulic machine to apply a pressure of 15-18 MPa after the temperature increase is completed.

[0023] Further preferably, the temperature maintenance is performed by maintaining the temperature at 120-130°C for a time calculated as t=a*d, where t is the temperature maintenance time in minutes, a is the magnesium-phenolic temperature maintenance coefficient with a value of 4-5 min / mm, and d is the total thickness of the probe temperature sensor protection bracket preform blank in mm.

[0024] Further preferably, the pressure maintenance is performed by adjusting the hydraulic machine to maintain the pressure in the range of 15-18 MPa during the temperature maintenance.

[0025] Further, the step (1) processes the probe temperature sensor protection bracket blank, and cuts the probe temperature sensor protection bracket blank into two half-cones, mills a flat surface on the half-cone to form a probe sensor reserved groove and a concave-convex semicircular positioning combination structure.

[0026] Further preferably, the half-cone has a skirt-shaped cross section and a semicircular top head.

[0027] Further preferably, the flat surface on the half-cone is milled to form a 5mm probe sensor reserved groove, and concave-convex circular combination structures are formed at both ends of the reserved groove.

[0028] Further, the step (2) wires the probe temperature sensor, and places the probe temperature sensor wire in the reserved groove of the probe temperature sensor protection bracket processed in the step (1).

[0029] Further, the step (2) bonds the probe temperature sensor, and fixes the probe temperature sensor by using a conventional 3M908 double-sided adhesive tape.

[0030] Further, the step (2) combines the probe temperature sensor supports, and positions and combines the two half-probe temperature sensor supports into a whole according to the concave-convex circular grooves.

[0031] Further, the step (2) detects the on-off of the probe temperature sensor, and tests the on-off of the probe temperature sensor by using a digital temperature controller or other equipment.

[0032] Further, the step (2) bonds and encapsulates the probe temperature sensor, and fixes the probe temperature sensor support by using a vacuum compaction method, injects magnesium phenolic resin into the other end of the vacuum nozzle, and then places it in a drying oven set at 120°C for curing for 12 hours.

[0033] Further, the step (2) processes the probe temperature sensor into a stepped shape, fixes the probe temperature sensor by using three conformal tooling, mills an irregular stepped groove by using a lathe, and obtains a probe temperature sensor built-in part.

[0034] Further, the step (3) prepares short fiber quartz / phenolic pre-mixture, and synchronously performs the operation of the step (1), and the fiber length of the quartz fiber bundle cut is not more than 15mm-20mm.

[0035] Further, step (3) described the assembly of the probe temperature sensor built-in, the probe temperature sensor built-in of step (2) is assembled with the metal end handle, the probe temperature sensor reserved line is led out from the reserved hole beside the upper mold, the silicone rubber adhesive is prepared, the reserved hole is blocked with silicone rubber, the temperature of the upper mold of the hydraulic machine is raised, and the silicone rubber is cured at a temperature of 80-120 DEG C for 4-8 hours.

[0036] Further, step (3) described the filling of the inner circle short fiber quartz / phenolic premix and preforming, the mold was preheated to 80-90 DEG C using a hydraulic machine, the premix with quartz fiber length of 15-20 mm was dried as in step (1), the premix preheating temperature was 80-90 DEG C, the preheating time was 20-30 min, and then it was loaded into the mold cavity to make it uniformly distributed outside the probe temperature sensor built-in, the mold temperature was set to 90 DEG C, the holding time was 30 min, and the pressure was 2-3 MPa.

[0037] Further, step (3) described the probe temperature sensor on-off detection, and step (2) detected the on-off condition of the probe temperature sensor.

[0038] Further, step (3) described the filling of the outer circle long fiber quartz / phenolic premix of the end product, the premix with quartz fiber length of 30-50 mm of step (1) was evenly loaded into the mold for 5 times, the mold temperature was kept at 80-90 DEG C during the loading, and the mold was pre-pressed multiple times using a hydraulic machine during the loading of the premix.

[0039] Further, step (3) described the mold pressing forming, the curing system was as follows: at 80-90 DEG C, holding for 20 min, heating to 150-160 DEG C at a heating rate of 2-3 DEG C / 10 min, applying pressure every 10 min during the heating, the pressure was set to 5 MPa, 10 MPa and 12 MPa in turn, the final pressure was 12-15 MPa, and holding at 150-160 DEG C for 20-24 h.

[0040] Further, step (3) described the probe temperature sensor testing, the temperature change data of the probe temperature sensor was detected in real time during the mold pressing forming.

[0041] Further, step (4) described the removal of the front part protection rod of the quartz / phenolic end structure product with embedded probe temperature sensor, and the part of the protection rod was removed according to the reserved size.

[0042] Further, step (4) described the post-curing of the end product in an oven, the drying temperature of the oven was set to 150-160 DEG C, and the drying time was 12-24 h, and the furnace was naturally cooled down.

[0043] (III) Beneficial Effects

[0044] The above-mentioned technical solution provides a quartz / phenolic resin end-molding method for embedded probe temperature sensors. This method fully utilizes the flexibility of the molding process, the designability of the materials, and the excellent ablation resistance of quartz fiber and phenolic resin. It avoids operational problems caused by the characteristics of the molding process and reduces the difficulty of component preparation. By using quartz / phenolic composite materials instead of traditional conical metal parts, the overall weight of the end is greatly reduced. The molded product has high dimensional accuracy, good internal quality, and low manufacturing cost. It meets the requirements for normal use of embedded probe temperature sensors without compromising the overall aerodynamic shape of the end. Through force and heat testing, the material selection and design of the end have been significantly improved. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the cross-sectional structure of the protective bracket for the probe temperature sensor.

[0046] Figure 2 A schematic diagram of the upper surface structure of the reserved slot and semi-circular positioning combination for the protective bracket of a half-probe temperature sensor.

[0047] Figure 3-1 , 3-2 These are the front view and left view of the metal end handle, respectively.

[0048] Figure 4 This is a schematic diagram of the cross-sectional structure of the upper mold.

[0049] Figure 5-1 , 5-2 These are the front view and left view of the end structure component, respectively.

[0050] The following are the labels in the diagram: 1. Stepped groove; 2. Protective bracket; 3. Convex circular positioning assembly structure; 4. Reserved groove; 5. Metal end handle; 6. Reserved hole; 7. Fixing pin hole; 8. End structure component; 9. Detailed Implementation

[0051] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0052] Reference Figures 1 to 5-2 As shown, the quartz / phenolic end molding method for the embedded probe temperature sensor in this embodiment includes the following processes:

[0053] (1) Molding and processing of the protective bracket for the probe temperature sensor

[0054] The quartz fiber tows are cut into 30mm-50mm, and an appropriate amount of magnesium phenolic resin is weighed, and the tows are mixed with the resin in a weight ratio of 6:4 to prepare the desired prepreg. The short fiber quartz / phenolic prepreg is preheated in an oven at a temperature of 80-90°C for 20-30 minutes. The short fiber quartz / phenolic prepreg is evenly loaded into the mold cavity of the pressing blank in two portions. The mold is closed, preheated, and heated, and then the temperature is maintained at 80-90°C for 40-50 minutes. When the temperature reaches 20-25 minutes, a hydraulic press is used to apply a pressure of 1-2 MPa. Then the temperature is raised to 120-130°C at a rate of 2-5°C / 10 min, and after the temperature is raised, the hydraulic press is used to apply a pressure of 15-18 MPa. The temperature is maintained at 120-130°C for a time t=a*d, where t is the holding time in minutes, a is the magnesium phenolic holding coefficient, and d is the total thickness of the probe temperature sensor protection bracket preform blank. During this period, the hydraulic press is adjusted to maintain the pressure in the range of 15-18 MPa.

[0055] The probe temperature sensor protection bracket blank is cut and milled into a cross-section as shown in Figure 1 The top head is two half-cones of a semi-cylinder, and the flat surface on the half-cone is machined as shown in Figure 2 The 5mm probe sensor reserved groove 5 and the reserved groove ends are machined with convex circular positioning combination structure 3 and concave circular positioning combination structure 4.

[0056] (2) Packaging of the probe temperature sensor

[0057] The probe temperature sensor is placed in the reserved groove 5 of the protection bracket. The probe temperature sensor is fixed by cutting and trimming the commonly used 3M908 double-sided tape in the market at the end points and the middle points of the sensor wiring. Then the Figure 1The two halves of the probe temperature sensor bracket shown are positioned and assembled into a whole using the convex circular positioning combination structure 3 and the concave circular positioning combination structure 4. The continuity of the probe temperature sensor is tested using a digital temperature controller or other equipment to ensure it functions properly. A vacuum bag is fabricated, with a pre-installed glue inlet and an exhaust port. Magnesium phenolic resin is prepared, the glue inlet pipe is connected, and the glue inlet switch is closed. The probe temperature sensor bracket is then compacted and fixed using vacuum compaction. The pre-installed concave-convex circular combination structure prevents the protective bracket from shifting. When the vacuum bag pressure is between 0.08 MPa and 0.1 MPa, the glue inlet switch is opened, and magnesium phenolic resin is injected. During the injection process, the resin needs to be de-bubbled until no more air bubbles are present in the resin flowing from the vacuum-sealed conduit. After the magnesium phenolic resin fills the vacuum bag, the exhaust valve is closed, and the bag is placed in a drying oven at 120°C for 12 hours of curing. Three conformal fixtures are used to fix the probe temperature sensor onto the machine tool, and the probe temperature sensor protective bracket is machined as shown. Figure 1 The irregular stepped groove 1 shown is used to obtain the probe temperature sensor built-in component.

[0058] (3) Forming of end parts

[0059] Following the same procedure as step (1), the quartz fiber bundles are cut into 15mm to 20mm pieces to prepare short-fiber quartz / phenolic premix. The following is a description of the process: Figure 1 The probe temperature sensor built-in component shown is assembled with the metal end handle shown in Figure 3, that is, the probe temperature sensor protective bracket 2 is inserted into the metal end handle 6, and the probe temperature sensor's reserved wire is led out as shown in Figure 3. Figure 4 The upper mold has a pre-drilled hole 7. A pin is used to fix the probe temperature sensor housing onto the mold by passing it through the fixing pin hole 8 of the metal end shank. Prepare a silicone rubber adhesive and seal the pre-drilled hole 7 with silicone rubber. Increase the temperature of the upper mold on the hydraulic press and cure the silicone rubber at 80℃~120℃ for 4h~8h. Preheat the mold to 80℃~90℃ using the hydraulic press. Preheat the premixed material with quartz fiber lengths of 15mm~20mm to 80℃ for 20min~30min. Then, fill the mold cavity with the premixed material, ensuring even distribution. Figure 1The probe temperature sensor built-in part is shown outside, the mold temperature is set to 90 DEG C, the holding time is 30 min, and the pressure is 2-3 MPa. The on-off condition of the probe temperature sensor is detected. Ensure that the probe temperature sensor works normally. The length of the quartz fiber of the premix is 30-50 mm, the preheating temperature is 80-90 DEG C, the preheating time is 20-30 min, then the premix is evenly loaded into the mold for 5 times, the mold temperature is kept at 80-90 DEG C during the loading, and the hydraulic machine is used to pre-press the mold multiple times during the loading. After the loading is completed, the end solidification forming is carried out, and the curing system is: at 80-90 DEG C, holding for 20 min, heating to 150-160 DEG C at a heating rate of 2-3 DEG C / 10 min, applying pressure every 10 min during heating, and the pressure is set to 5 MPa, 10 MPa and 12 MPa in turn, and the final pressure is 12-15 MPa, and the temperature is kept at 150-160 DEG C for 20-24 h. In the process of mold pressing, the temperature change data of the probe temperature sensor is detected in real time.

[0060] (4) Processing of end product

[0061] After curing, the end is demolded using the ejection device, and the quartz / phenolic end structure product with embedded probe temperature sensor is roughed according to the reserved size. In order to ensure that the magnesium phenolic resin is completely cured, the end product is placed in an oven for post-curing, the drying temperature of the oven is set to 150-160 DEG C, and the drying time is 12-24 h. After curing, the temperature is naturally lowered in the oven. The quartz / phenolic end structure product 9 with embedded probe temperature sensor is obtained as shown in Figure 5.

[0062] From the above technical solutions, the present application has the following remarkable features:

[0063] (1) The probe temperature sensor is innovatively built into the end, realizing the overall mold pressing of the end.

[0064] (2) Compared with other preparation processes, the probe temperature sensor is directly built-in without machining and bonding, ensuring the pneumatic shape of the end.

[0065] (3) The composite built-in part is used instead of the metal built-in part, reducing the weight of the end.

[0066] (4) The design of the stepped protective support combined with the random distribution of the short fibers during mold pressing improves the interface bonding strength of the built-in part and the end.

[0067] (5) The probe temperature sensor bonding packaging further protects the probe temperature sensor, avoiding damage to the sensor in subsequent molding.

[0068] (6) The mould pressing forming method is reliable, has high repeatability, and has reasonable process coordination relationship, and reduces the forming process difficulty.

[0069] (7) The curing characteristics of phenolic resin are fully utilized, a gradient forming temperature level is set, the support bracket is pre-cured, and then the end head is co-cured to form a scheme, and the mechanical properties and thermal properties of the part are improved.

[0070] The above only describes the preferred embodiments of the present application, and it should be noted that for ordinary skilled persons in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications should be considered as the protection scope of the present application.

Claims

1. A method for molding the quartz / phenolic end of an embedded probe temperature sensor, characterized in that, It comprises the following steps: (1) The forming and processing of the probe temperature sensor protection bracket: the bracket is divided into two parts, the center butt joint groove is used for arranging the sensor, and the butt joint surface is provided with a positioning convex and a positioning groove; short fiber quartz / phenolic premix is prepared, the mold is filled, the probe temperature sensor protection bracket preform is pressed, and the probe temperature sensor protection bracket blank is processed to obtain a tapered probe temperature sensor protection bracket; the end of the bracket is provided with a protection rod for avoiding damage to the sensor during the closing of the press in step (3); (2) The packaging of the probe temperature sensor: probe temperature sensor wiring, probe temperature sensor bonding, probe temperature sensor bracket assembly, probe temperature sensor on-off detection, probe temperature sensor bonding and packaging, probe temperature sensor bracket curing, processing into irregular stepped grooves, and obtaining a probe temperature sensor built-in part; (3) The forming of the end product: short fiber quartz / phenolic premix is prepared, the probe temperature sensor built-in part is placed into the end mold, the inner ring short fiber quartz / phenolic premix is filled in the end mold, preforming is performed, the probe temperature sensor on-off detection is performed, the outer ring long fiber quartz / phenolic premix of the end product is filled, and the probe temperature sensor is tested to obtain a quartz / phenolic end product with a built-in probe temperature sensor; the end product mold comprises an upper mold and a lower mold, the upper mold is used for fixing the probe temperature sensor built-in part and is an inverted convex shape, the top plane thereof is in contact with the press, the bottom surface is provided with an built-in part positioning groove, and the positioning pins are arranged on the two side steps and are in butt joint with the lower mold; the lower mold is a concave shape and comprises a mold cavity for forming the end product, the filling process is centered on the probe temperature sensor built-in part, the inner ring of the end product is defined as surrounding the probe temperature sensor built-in part, and the outer ring of the end product is defined as surrounding the inner surface of the lower mold cavity; (4) The processing of the end product: the quartz / phenolic end product with a built-in probe temperature sensor is obtained by removing the front part protection rod through machining and placing the end product in an oven for post-curing.

2. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 1 wherein, In step (1), the short fiber quartz of the short fiber quartz / phenolic is a reinforcing material, the quartz fiber tows are cut, and the length of the cut fibers is not more than 30mm-50mm; the matrix material of the short fiber quartz / phenolic premix is one or a mixture of several of ammonia-phenolic resin, magnesium-phenolic resin, and boron-phenolic resin; and the resin of the short fiber quartz / phenolic premix is magnesium-phenolic resin.

3. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 2 wherein, In step (1), the short fiber quartz / phenolic premix is preheated in an oven when the mold is filled, the preheating temperature is 80-90℃, the preheating time is 20-30min, and the short fiber quartz / phenolic premix is evenly filled into the mold cavity in two times.

4. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 3 wherein, In step (1), the pressing probe temperature sensor protection bracket preform blank is obtained by closing the mold, pre-heating, maintaining temperature, adding contact pressure, heating, pressurizing, maintaining temperature, maintaining pressure, and the like; the mold is closed on the hydraulic machine; the mold temperature is heated by an electric heating rod to 80-90 DEG C from room temperature in 40-45 min; the mold temperature is maintained at 80-90 DEG C for 40-50 min; the contact pressure is added by using the hydraulic machine to apply a pressure of 1-2 MPa after maintaining temperature for 20-25 min; the temperature is raised to 120-130 DEG C at a rate of 2-5 DEG C / 10 min; the pressure is applied by using the hydraulic machine to apply a pressure of 15-18 MPa after heating is completed; the maintaining time at 120-130 DEG C is calculated as t=a*d, wherein t is the maintaining time in min, a is the phenolic resin maintaining coefficient in the range of 4-5 min in min / mm, and d is the total thickness of the probe temperature sensor protection bracket preform blank in mm; the pressure is maintained by adjusting the hydraulic machine to keep the pressure of the press in the range of 15-18 MPa during maintaining.

5. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 4 wherein, In step (1), the probe temperature sensor protection bracket blank is obtained by cutting and milling the probe temperature sensor protection bracket blank into two half-cones, and milling a probe sensor reserved groove and a concave-convex semicircular positioning combination structure on the half-cones; the half-cone has a skirt-shaped cross section and a semicircular top head; the probe sensor reserved groove and the concave-convex semicircular positioning combination structure are milled on the half-cone, a 5 mm probe sensor reserved groove is milled on the half-cone, and concave-convex circular combination structures are respectively formed at both ends of the reserved groove.

6. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 5 wherein, In step (2), the probe temperature sensor is placed in the reserved groove of the probe temperature sensor protection bracket processed in step (1); the probe temperature sensor is fixed by using a conventional 3M908 double-sided adhesive tape; the two half-probe temperature sensor brackets are positioned and combined into a whole according to the concave-convex circular groove; the on-off of the probe temperature sensor is tested by using a digital temperature controller or other equipment; the probe temperature sensor is packaged by vacuum compaction, magnesium phenolic resin is injected into the other end of the vacuum nozzle, and then the probe temperature sensor is placed in a drying oven and set at 120 DEG C for 12 hours; the probe temperature sensor is fixed by using three conformal toolings, an irregular stepped groove is turned by a lathe, and the probe temperature sensor built-in part is obtained.

7. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 6 wherein, In step (3), the preparation of short fiber quartz / phenolic premix synchronously step (1) is operated in the same way, the fiber length of the quartz fiber bundle cut is not more than 15mm-20mm; the probe temperature sensor built-in is assembled with the metal end handle, the probe temperature sensor reserved line is led out from the reserved hole beside the upper mold, the silicone rubber adhesive is prepared, the silicone rubber is blocked in the reserved hole, the upper mold temperature of the hydraulic machine is raised, and the silicone rubber is cured at a temperature of 80-120℃ for 4-8h.

8. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 7 wherein, In step (3), the loading of the inner circle short fiber quartz / phenolic premix and preforming, the mold is preheated to 80-90℃ using a hydraulic machine, the premix with quartz fiber length of 15-20mm is dried as in synchronous step (1), the premix preheating temperature is 80-90℃, the preheating time is 20-30min, and then it is loaded into the mold cavity to make it uniformly distributed outside the probe temperature sensor built-in, the mold temperature is set to 90℃, the holding time is 30min, and the pressure is 2-3MPa; the probe temperature sensor is detected, and the on-off condition of the probe temperature sensor is detected in synchronous step (2).

9. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 8 wherein, In step (3), the loading of the outer circle long fiber quartz / phenolic premix of the end piece, the premix with quartz fiber length of 30-50mm in step (1) is evenly loaded into the mold for 5 times, and the mold temperature is kept at 80-90℃ during the loading; the premix is pre-pressed by the hydraulic machine during the loading; the mold pressing is performed, the curing system is as follows: at 80-90℃, holding for 20min, heating to 150-160℃ at a heating rate of 2-3℃ / 10min, applying pressure every 10min during the heating, the pressure is set to 5MPa, 10MPa and 12MPa in turn, the final pressure is 12-15MPa, and holding at 150-160℃ for 20-24h; the probe temperature sensor is tested, and the temperature change data of the probe temperature sensor is detected in real time during the mold pressing.

10. The in-line probe temperature sensor quartz / phenolic tip compression molding process of claim 9 wherein, In step (4), the quartz / phenolic end piece structure with embedded probe temperature sensor is machined to remove the front part of the protective rod according to the reserved size; the end product is placed in the oven for post-curing, the drying temperature of the oven is set to 150-160℃, and the drying time is 12-24h, and the furnace is naturally cooled.

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