Glue injection type sealing blowout preventer and wellhead emergency sealing method

Abstract

The application provides a glue injection type sealed blowout preventer and a wellhead emergency sealing method, and relates to the technical field of oil and gas exploitation. The blowout preventer comprises a valve body, a metal sealing glue injection cavity sleeve, a lead screw driving mechanism and a glue injection system. The metal sealing glue injection cavity sleeve comprises two split cavity sleeves, is internally provided with a glue injection cavity, is made of brass or red copper, and is provided with front and rear sealing conical surfaces. The lead screw is connected with the cavity sleeve through an eccentric hole, the center axis of the eccentric hole is offset from the center axis of the cavity sleeve, and the cavity sleeve can only move linearly. When the polished rod seal fails, the cavity sleeve is driven by a handle to tightly wrap the polished rod, glue is injected to form a sealed whole, and rapid emergency sealing is realized. The application solves the problem of emergency plugging after the polished rod seal fails under high temperature and high pressure conditions such as heavy oil thermal recovery, and improves the safety of wellhead operation.

Description

Technical Field

[0001] This invention relates to the field of oil and gas extraction technology, specifically to a method for sealing a blowout preventer gate with adhesive injection and for emergency sealing of the wellhead. Background Technology

[0002] In daily oilfield production and operation, wellheads must be kept sealed to ensure safe production and prevent environmental pollution caused by leaks, spills, and other contaminants. Heavy oil extraction commonly employs steam injection thermal recovery. During the steam injection phase, the polished rod seal packing must withstand both high temperatures and high pressures. Due to the high viscosity and poor fluidity of heavy oil, high-temperature steam needs to be injected during thermal recovery to reduce crude oil viscosity and improve extraction efficiency. This process requires the wellhead sealing system to withstand long-term high temperatures above 300℃ and high pressures of 15-20 MPa.

[0003] In existing technologies, injection-production dual-purpose seals used at heavy oil wellheads primarily employ graphite and rubber as sealing materials. However, these traditional sealing materials exhibit significant drawbacks under high-temperature and high-pressure environments. Graphite packings are prone to oxidation and deterioration at high temperatures, leading to a sharp decline in sealing performance; rubber-based sealing materials undergo thermal aging, hardening, and even decomposition at high temperatures, resulting in seal failure. In actual production, the sealing packings used in the upper and lower stage packing chambers are susceptible to wear, causing frequent instances of incomplete closure of the lower-stage seal. This severely impacts the replacement of the upper-stage sealing packings, causing significant disruption to production and posing potential safety hazards.

[0004] Once a leak occurs during steam injection, it is extremely difficult to handle, easily leading to serious economic losses and environmental pollution. Traditional methods involve immediately shutting down the well, cutting off the pressure source, and then replacing the sealing packing. This process is not only time-consuming and costly, but also fails to effectively control wellhead leakage during the seal failure period, posing safety hazards and environmental pollution risks. Especially during steam injection and fluid extraction operations, the rapid changes in wellhead pressure and temperature make the sealing packing more prone to sudden failure, and current technologies lack effective emergency sealing methods.

[0005] The existing technical solution to this problem mainly involves timely replacement of worn polished rod seal packing. New packing must be replaced before steam injection and fluid extraction to prevent seal failure. While this preventative replacement approach can reduce seal failure to some extent, it has the following drawbacks: First, preventative replacement cannot completely prevent sudden failure of the seal packing under extreme operating conditions; second, frequent replacement of the seal packing not only increases material and labor costs but also affects the normal production rate of the oil well; most importantly, this approach cannot fundamentally solve the problem of wellhead leakage and timely seal restoration after polished rod seal failure.

[0006] When seal failure occurs, current technology lacks rapid and effective emergency sealing measures. Operators often have to resort to passive measures such as shutting down the well and depressurizing, followed by replacement of the sealing packing. The entire process is time-consuming, with continuous wellhead leakage during this period, causing not only crude oil loss and environmental pollution but also posing safety risks to production. In certain emergency situations, such as when the sealing packing completely fails and there is insufficient spare packing, it may even be necessary to shut down the well for an extended period while waiting for material supplies, severely disrupting the normal production order of the oilfield. Summary of the Invention

[0007] The purpose of this invention is to provide a wellhead polished rod sealing device suitable for various working conditions, which can provide emergency sealing in a timely manner after the sealing packing fails, quickly prevent wellhead leakage, and improve and ensure the safety and reliability of wellhead sealing packing replacement and other operations. At the same time, it has the ability to withstand high temperature and high pressure working environment and meets the technical requirements of special processes such as heavy oil thermal recovery.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A glue-injection type sealed blowout preventer includes a glue-injection type sealed blowout preventer valve body, a metal-sealed glue-injection cavity sleeve, a screw drive mechanism, and a glue-injection system. The glue-injection type sealed blowout preventer valve body has a channel for a light rod to pass through, and the valve body has a valve body sealing step. The metal-sealed glue-injection cavity sleeve includes two separate cavities, each with a light rod hole for the light rod to pass through. The two separate cavities are arranged opposite each other and can be brought together to surround the light rod. A glue-injection cavity is provided within the metal-sealed glue-injection cavity sleeve, and the glue-injection cavity is connected to the glue-injection system on the glue-injection type sealed blowout preventer valve body. The screw drive mechanism includes a screw and a screw handle. The screw is connected to the metal-sealed glue-injection cavity sleeve through an eccentric hole, the central axis of which is offset from the central axis of the metal-sealed glue-injection cavity sleeve. When the screw handle drives the screw, the metal-sealed glue-injection cavity sleeve can only move linearly along the axial direction and cannot rotate.

[0010] Furthermore, the metal sealing injection cavity sleeve is made of a metal with a hardness less than that of the polished rod, and the metal sealing injection cavity sleeve is made of brass or copper.

[0011] Furthermore: the metal sealing injection cavity sleeve is provided with a front sealing cone surface and a rear sealing cone surface, and the valve body sealing step is provided with a front cone surface and a rear cone surface that cooperate with the front sealing cone surface and the rear sealing cone surface of the injection cavity sleeve.

[0012] Furthermore: the injection cavity is a hemispherical cavity, and the metal sealing injection cavity sleeve is provided with an injection cavity sleeve inlet hole and an injection cavity sleeve outlet hole that communicate with the injection cavity.

[0013] Furthermore, the inner surface of the glue-injection type sealing anti-blowout gate valve body is provided with an annular glue storage groove corresponding to the glue outlet hole of the glue injection cavity sleeve.

[0014] Furthermore, the glue outlet holes of the glue injection cavity are multiple holes evenly distributed at the end of the glue injection cavity.

[0015] Furthermore, the glue injection system includes a valve body glue injection nozzle, a valve body glue outlet, and a stop plug. The valve body glue injection nozzle is connected to the glue inlet hole of the glue injection cavity, and the valve body glue outlet is connected to the valve body annular glue storage tank.

[0016] Furthermore, the lead screw drive mechanism includes left and right lead screw handles disposed at both ends of the glue-injection type sealing anti-blowout gate valve body, which drive the metal sealing glue injection cavity sleeve to move by synchronously rotating the left and right lead screw handles.

[0017] The present invention also provides a method for emergency sealing of wellheads using the above-mentioned glue-injection type blowout preventer, comprising the following steps:

[0018] S1: When the wellhead polished rod seal failure is detected, turn the screw handle clockwise to push the metal seal injection cavity sleeve forward, so that the two split cavity sleeves on the left and right come together and tightly wrap the polished rod.

[0019] S2: When the sealing cone surface of the metal sealing injection cavity sleeve forms a line seal with the valve body sealing step, stop rotating the screw handle.

[0020] S3: The sealing adhesive is injected into the injection cavity through the adhesive injection system. The sealing adhesive exits from the adhesive hole of the injection cavity and enters the annular adhesive storage tank of the valve body to form a sealed whole.

[0021] S4: When the sealing adhesive overflows from the dispensing hole of the valve body, stop the dispensing process and complete the emergency sealing.

[0022] Further: When production needs to be resumed, perform the following steps:

[0023] Turn the lead screw handle counterclockwise, and the lead screw will drive the metal sealing injection cavity sleeve to move backward;

[0024] When the front sealing cone surface of the metal sealing injection cavity sleeve forms a line seal with the valve body sealing step, stop rotating the lead screw handle;

[0025] The downward movement of the guide rod is initiated, which crushes the sealant in the dispensing cavity into particles and carries them away.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] I. This invention solves the problem of rapid emergency sealing after the polished rod seal fails. When the polished rod seal at the wellhead fails and leaks, the operator can quickly start the emergency sealing procedure by simply turning the handle. The entire sealant injection process can be completed within minutes. Compared with traditional methods such as shutting down the well, depressurizing, and replacing the sealing packing, this invention can promptly stop wellhead leakage and quickly restore the seal, fundamentally solving the problem that existing technologies cannot handle seal failure in an emergency.

[0028] II. This invention significantly improves the sealing capacity under extreme conditions such as heavy oil thermal recovery. This invention uses a metal sealing injection cavity sleeve to replace traditional rubber, graphite, and other sealing fillers. The metal material can withstand working environments with temperatures above 300°C and pressures of 15-20 MPa during the steam injection stage. Combined with a double-line sealing mechanism, it solves the problem of traditional sealing fillers easily failing during steam injection and liquid extrusion operations.

[0029] Third, this invention achieves reusable emergency seals. The eccentric hole design enables precise opening and closing control of the metal cavity sleeve, allowing for rapid unsealing when production needs to resume. The movement of the smooth rod crushes and carries away the colloid, avoiding the single-use limitation of traditional emergency measures and solving the problem of quickly resuming production after the sealant has been replaced. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall appearance of the glue-injection type sealing blowout preventer gate of the present invention; Figure 2 This is a schematic cross-sectional view of the internal structure of the glue-injection type sealing blowout preventer gate of the present invention; Figure 3 This is a schematic cross-sectional view of the internal structure of the glue-injection sealed blowout preventer valve body of the present invention; Figure 4 This is a schematic diagram of the metal sealing injection cavity sleeve structure of the injection-type sealing blowout preventer of the present invention; Figure 5 This is a schematic front view of the metal sealing injection cavity sleeve structure of the injection-type sealing blowout preventer of the present invention;

[0031] In the picture:

[0032] 1. Valve body injection nozzle; 2. Valve body glue outlet; 3. Stop plug; 4. Glue inlet of injection chamber sleeve; 5. Glue outlet of injection chamber sleeve; 6. Valve body annular glue storage groove; 7. Valve body sealing step; 8. Rear sealing cone surface of injection chamber sleeve; 9. Stroke groove of injection chamber sleeve; 10. Front sealing cone surface of injection chamber sleeve; 11. Lead screw; 12. Eccentric hole; 13. Lead screw sealing packing; 14. Front cone surface of valve body sealing step; 15. Rear cone surface of valve body sealing step; 16. Glue injection chamber; 17. Smooth rod hole of injection chamber sleeve; 18. Glue injection type sealed blowout preventer valve body; 19. Pressure cap; 20. Sealing packing; 21. Pressure cap; 22. Smooth rod; 23. Lead screw handle; 24. Metal sealing injection chamber sleeve. Detailed Implementation

[0033] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0035] like Figure 1 and Figure 2 As shown, the glue-injection type sealed blowout preventer of the present invention includes a glue-injection type sealed blowout preventer valve body 18, a metal sealing glue injection cavity sleeve 24, a screw drive mechanism, and a glue injection system. The glue-injection type sealed blowout preventer valve body 18 is the main structure of the entire device, and has a central channel for the light rod 22 to pass through. The glue-injection type sealed blowout preventer valve body 18 is provided with a valve body sealing step 7, which includes a front conical surface 14 and a rear conical surface 15 for forming a line seal with the metal sealing glue injection cavity sleeve 24.

[0036] The metal sealing injection cavity sleeve 24 is the core innovative component of this invention. The metal sealing injection cavity sleeve 24 is made of a metal with a hardness less than that of the polished rod 22. In a preferred embodiment, the metal sealing injection cavity sleeve 24 is made of brass or copper, which effectively reduces the wear of the polished rod 22 and has excellent high-temperature and pressure resistance. The metal sealing injection cavity sleeve 24 includes two separate cavity sleeves, left and right. Each separate cavity sleeve has an injection cavity sleeve polished rod hole 17 of the same diameter as the polished rod 22, allowing the polished rod 22 to pass through smoothly. The two separate cavity sleeves are arranged opposite each other, able to come together to surround the polished rod 22, achieving an annular sealing of the polished rod 22. A hemispherical injection cavity 16 is milled at the center of the metal sealing injection cavity sleeve 24; this injection cavity 16 serves as a storage and distribution space for the sealing adhesive. The smooth rod 22 is located above the smooth rod hole 17 in the glue injection cavity. The glue injection type sealing blowout preventer valve body 18 is filled with sealing filler 20 that wraps the smooth rod 22. A pressure cap 19 is pressed on the sealing filler 20. A pressure cap 21 is covered on the pressure cap 19. The pressure cap 21 is connected to the glue injection type sealing blowout preventer valve body 18 by threads.

[0037] like Figure 4 and Figure 5As shown, the metal sealing injection cavity sleeve 24 has a front sealing cone surface 10 and a rear sealing cone surface 8, which are located at the front and rear ends of the cavity sleeve, respectively. A stroke groove 9 is provided between the front sealing cone surface 10 and the rear sealing cone surface 8. The front sealing cone surface 10 is used to cooperate with the front cone surface 14 of the valve body sealing step to form a line seal when the cavity sleeve is separated. The rear sealing cone surface 8 is used to cooperate with the rear cone surface 15 of the valve body sealing step to form a line seal when the cavity sleeve is closed. This dual line seal design ensures good sealing performance under different operating conditions.

[0038] The metal sealing cavity sleeve 24 is provided with a glue inlet hole 4 and a glue outlet hole 5 communicating with the glue cavity 16. The glue inlet hole 4 is used for injecting the sealing adhesive, and the glue outlet hole 5 is configured as multiple holes evenly distributed at the end of the glue cavity 16, typically four on each side, for the sealing adhesive to flow outward. Figure 3 As shown, an annular glue storage groove 6 is provided on the inner surface of the glue injection type sealing blowout preventer valve body 18 at the position corresponding to the glue outlet hole 5 of the glue injection cavity sleeve. When the sealing glue flows out from the glue outlet hole 5 of the glue injection cavity sleeve, it can enter the annular glue storage groove 6 of the valve body and be distributed therein, and cooperate with the metal sealing glue injection cavity sleeve 24 to form a complete sealing whole.

[0039] The lead screw drive mechanism includes a lead screw 11 and left and right lead screw handles 23 located at both ends of the glue-injection sealed blowout preventer valve body 18. The gap between the lead screw 11 and the glue-injection sealed blowout preventer valve body 18 is filled with lead screw sealing filler 13 to increase the sealing performance at the lead screw 11. The lead screw 11 is connected to the metal sealing glue injection cavity sleeve 24 through an eccentric hole 12, which is a key innovative design of this invention. The central axis of the eccentric hole 12 is offset from the central axis of the metal sealing glue injection cavity sleeve 24. This eccentric design ensures that when the lead screw handle 23 drives the lead screw 11 to rotate, the metal sealing glue injection cavity sleeve 24 can only move linearly along the axial direction and cannot rotate accordingly. By synchronously rotating the left and right lead screw handles 23, the synchronous movement of the two separate cavities can be achieved, ensuring the accuracy of cavity closing and opening.

[0040] The adhesive injection system includes a valve body injection nozzle 1, a valve body outlet hole 2, and a stop plug 3. The valve body injection nozzle 1 is located on the side of the valve body 18 of the adhesive injection type sealing blowout preventer and communicates with the inlet hole 4 of the injection chamber sleeve, used to connect the adhesive injection equipment to inject the sealing adhesive. The valve body outlet hole 2 is located on the upper part of the valve body 18 and communicates with the valve body annular storage tank 6. When the sealing adhesive fills the injection chamber 16 and the valve body annular storage tank 6, it overflows from this hole, serving as a criterion for determining whether adhesive injection is complete. The stop plug 3 is used to seal the valve body injection nozzle 1 and the valve body outlet hole 2 when not in the adhesive injection state, preventing impurities from entering and adhesive leakage.

[0041] The working principle of this invention is as follows: When the oil well shows signs of leakage or requires steam injection or other measures, the two end screw handles 23 are first rotated clockwise, and the screw 11 pushes the metal sealing injection cavity sleeve 24 with the eccentric hole 12. Due to the design of the eccentric hole 12, the metal sealing injection cavity sleeve 24 cannot rotate and can only move forward in a straight line. When the left and right metal sealing injection cavity sleeves 24 come together and the injection cavity sleeve polished rod hole 17 is used to tightly wrap the polished rod 22, the rear sealing cone surface 8 of the injection cavity sleeve and the rear cone surface 15 of the valve body sealing step form a line seal, which constitutes the second seal on both sides inside the injection-type sealed blowout preventer valve body 18.

[0042] Next, the sealing adhesive injection operation is performed. Unscrew the plug 3 and the screw on the valve body outlet hole 2, and connect the sealing adhesive injection device to the valve body injection nozzle 1. Rotate the handle of the injection device to force the sealing adhesive from the valve body injection nozzle 1 through the injection cavity inlet hole 4 into the injection cavity 16. After the sealing adhesive is distributed within the injection cavity 16, it mainly flows out through the evenly distributed injection cavity outlet holes 5 and enters the valve body annular storage tank 6. When the sealing adhesive fills the injection cavity 16 and the valve body annular storage tank 6, it will overflow from the valve body outlet hole 2 at the top of the sealing blowout preventer valve body 18. At this point, stop the injection and retighten the plug 3 and the screw on the valve body outlet hole 2. At this time, the sealing adhesive forms a high-strength, high-temperature and high-pressure resistant seal in the center and on both sides of the metal sealing injection cavity sleeve 24, isolating the wellhead pressure below the metal sealing injection cavity sleeve 24 and preventing leakage of the oil well's produced fluid.

[0043] When the steam injection stage is completed or the sealing packing 20 is replaced, and it is necessary to resume production operation of the pumping well, turn the screw handles 23 at both ends counterclockwise, using the screw 11 to drive the metal sealing injection cavity sleeve 24 to move backward. When the front sealing cone surface 10 of the metal sealing injection cavity sleeve 24 contacts the front cone surface 14 of the valve body sealing step to form a line seal, stop turning the screw handle 23. At this time, the left and right metal sealing injection cavity sleeves 24 are completely separated from the polished rod 22, making room for the movement of the polished rod 22. When the polished rod 22 begins to move downward, because the capacity of the injection cavity 16 is relatively small, the sealing adhesive in it is easily crushed into particles by the polished rod 22 and carried away by the oil flow, thus completing the pumping operation of the pumping well.

[0044] The innovation of this invention lies in the first-time use of metal to fabricate the metal sealing injection cavity sleeve 24. Compared to traditional materials such as rubber and graphite, the metal shell can withstand higher temperatures and pressures. The annular glue storage groove 6 on the glue-injection sealed blowout preventer valve body 18 cooperates with the metal sealing injection cavity sleeve 24, achieving better high-temperature and high-pressure resistance after glue injection. The eccentric hole 12 design enables precise linear motion control of the metal sealing injection cavity sleeve 24, avoiding rotational interference and improving operational reliability and accuracy. The double-line sealing mechanism further enhances the entire system's ability to withstand high temperatures and pressures, effectively improving the speed and effectiveness of the glue injection sealing operation.

[0045] This technical solution significantly improves the resistance of the sealant injection to high temperatures and pressures, reduces the amount of sealant used, shortens the sealing time, and improves operational efficiency. It also achieves rapid sealing, rapid unsealing, and flexible opening and closing, meeting the technical requirements of wellhead sealing for various oil wells. It is particularly suitable for emergency sealing needs under high-temperature and high-pressure conditions such as heavy oil thermal recovery, providing crucial technical support for the development of green oilfields.

[0046] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent transformations or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A glue-injection type sealed blowout preventer, characterized in that, The device includes a glue-injection type sealed blowout preventer valve body, a metal-sealed glue-injection cavity sleeve, a screw drive mechanism, and a glue-injection system. The glue-injection type sealed blowout preventer valve body has a channel for a light rod to pass through, and a valve body sealing step is provided on the valve body. The metal-sealed glue-injection cavity sleeve includes two separate cavities, each with a glue-injection cavity sleeve light rod hole for the light rod to pass through. The two separate cavities are arranged opposite each other and can be brought together to surround the light rod. A glue-injection cavity is provided within the metal-sealed glue-injection cavity sleeve, and the glue-injection cavity is connected to the glue-injection system on the glue-injection type sealed blowout preventer valve body. The screw drive mechanism includes a screw and a screw handle. The screw is connected to the metal-sealed glue-injection cavity sleeve through an eccentric hole, and the central axis of the eccentric hole is offset from the central axis of the metal-sealed glue-injection cavity sleeve. When the lead screw handle drives the lead screw, the metal sealing injection cavity sleeve can only move linearly along the axial direction and cannot rotate; The glue injection cavity is a hemispherical cavity, and the metal sealing glue injection cavity sleeve is provided with a glue injection cavity sleeve inlet hole and a glue injection cavity sleeve outlet hole that communicate with the glue injection cavity. The inner surface of the glue-injection type sealing anti-blowout gate valve body is provided with an annular glue storage groove corresponding to the glue outlet hole of the glue injection chamber sleeve; the glue injection system includes a valve body glue injection nozzle, a valve body glue outlet hole and a stop plug, the valve body glue injection nozzle is connected to the glue inlet hole of the glue injection chamber sleeve, and the valve body glue outlet hole is connected to the valve body annular glue storage groove. The glue injection cavity has multiple glue outlet holes evenly distributed at the end of the glue injection cavity.

2. The injection-type sealed blowout preventer according to claim 1, characterized in that, The metal sealing injection cavity sleeve is made of a metal with a hardness less than that of the polished rod, and the metal sealing injection cavity sleeve is made of brass or copper.

3. The injection-type sealing blowout preventer according to claim 1, characterized in that, The metal sealing injection cavity sleeve is provided with a front sealing cone surface and a rear sealing cone surface, and the valve body sealing step is provided with a front cone surface and a rear cone surface that cooperate with the front sealing cone surface and the rear sealing cone surface of the injection cavity sleeve.

4. The injection-type sealing blowout preventer according to claim 1, characterized in that, The lead screw drive mechanism includes left and right lead screw handles located at both ends of the glue-injection type sealing anti-blowout gate valve body. The metal sealing glue injection cavity sleeve is moved by synchronously rotating the left and right lead screw handles.

5. A method for emergency sealing of a wellhead using the injection-type blowout preventer gate as described in any one of claims 1-4, characterized in that, Includes the following steps: S1: When the wellhead polished rod seal failure is detected, turn the screw handle clockwise to push the metal seal injection cavity sleeve forward, so that the two split cavity sleeves on the left and right come together and tightly wrap the polished rod. S2: When the sealing cone surface of the metal sealing injection cavity sleeve forms a line seal with the valve body sealing step, stop rotating the screw handle. S3: The sealing adhesive is injected into the injection cavity through the adhesive injection system. The sealing adhesive exits from the adhesive hole of the injection cavity and enters the annular adhesive storage tank of the valve body to form a sealed whole. S4: When the sealing adhesive overflows from the dispensing hole of the valve body, stop the dispensing process and complete the emergency sealing.

6. The method according to claim 5, characterized in that, When production needs to be resumed, follow these steps: Turn the lead screw handle counterclockwise, and the lead screw will drive the metal sealing injection cavity sleeve to move backward; When the front sealing cone surface of the metal sealing injection cavity sleeve forms a line seal with the valve body sealing step, stop rotating the lead screw handle; The downward movement of the guide rod is initiated, which crushes the sealant in the dispensing cavity into particles and carries them away.

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