CN103806836B - Self-advancing type rotating jet jet rose - Google Patents

Abstract

The invention relates to a self-propelled rotary jet multi-hole nozzle. Including: Nozzle Cap, Back End Shaft, Screws, etc. Its basic working principle is: on the front face of the nozzle, on a circle with a certain distance away from the center, there are a plurality of nozzles whose central axis is in the vertical plane where a tangent line of the circle is located, and which are distributed at different angles to the axis of the nozzle cap. For the forward hole, the projection of the hole axis in the front face is the tangent of the same circle, so the jet has a high tangential velocity, which is conducive to efficient rock breaking; the jet is diffused and has a large range of action, which is conducive to the formation of large-diameter holes; the jet reaction makes the nozzle The cap rotates, and each hole scans along its own orbit to complete the rock breaking, forming more regular holes; the nozzle cap rotates, which is beneficial to the self-advancement of the nozzle. The rearward nozzle provides self-propelling force, and at the same time, it can control the rotation of the nozzle cap. The invention has a simple structure, can effectively break rocks, and form large-diameter regular holes.

Description

Self-propelled rotary jet multi-hole nozzle

technical field

The invention relates to the field of oil exploitation, and is a core component of the ultra-short-radius radial horizontal well technology of the new drilling technology, that is, a novel self-propelled rotary jet multi-hole nozzle. The invention can realize high-efficiency rock breaking while providing self-propelling force, and form relatively regular and large-diameter holes.

Background technique

Ultra-short radius sidetracking horizontal well drilling technology (also known as radial horizontal well drilling technology) refers to drilling one or more horizontal wellbores radially distributed in a vertical wellbore. This technology is a new oil field stimulation technology developed in recent decades. Utilizing this technology can revive dead wells, greatly increase oil well production and crude oil recovery, and can reduce drilling costs. It is an effective means for revitalizing old wells in oilfields, tapping reservoir potential, and stabilizing and increasing production. It is especially suitable for thin oil layers and vertical fractures. , heavy oil, low permeability and other reservoir development. However, the development of this technology is slow, and there are mainly the following four problems to be solved urgently: 1) to form holes with a certain diameter; 2) to have a certain jet drilling speed; 3) to be able to achieve a certain extension length; eyelets.

The key components of ultra-short radius radial horizontal well drilling technology include: skewer and hydraulic rock breaking bit. Among them, the hydraulic rock breaking drill bit is the key to forming horizontal holes. At present, there are mainly three structural forms with different designs and working principles, namely, multi-hole jet nozzle, single-hole rotating jet nozzle and straight-rotating mixed jet nozzle. All three structures can be self-advancing through reasonable design.

The first type of drill bit is a multi-hole nozzle, that is, the single-hole nozzle is changed into a multi-hole nozzle, and there are multiple nozzles distributed on the center of the front face and a ring at a certain distance from the center, and each nozzle guides the jet at an appropriate angle to hit the front of the drill bit. On the rock in a certain area, the rock has been eroded and broken to form a large horizontal hole. However, the rock breaking method of this method is impact crushing, so the jet energy utilization efficiency is low; and the recoil force of the forward nozzle is relatively large, which is not conducive to forward drilling.

The second type is a single-hole rotary jet drill bit, which is formed by adding a flow guide element inside a common nozzle. When the high-pressure fluid enters the nozzle cavity and flows through the flow guide element, under the guidance of the flow guide element, the fluid rotates along a certain trajectory to achieve a rotating jet with three-dimensional velocity under the condition that the nozzle does not rotate. Because the rotating jet has three-dimensional velocity, it can reduce the rock-breaking threshold pressure. On any jet section away from the nozzle, there is a circular area with the largest jet density and energy, and the greater the distance within a certain range, the larger the radius of the circular ring, and the larger the rock area broken by the jet. Therefore, as long as the pressure is sufficient, a large enough wellbore can be formed quickly. However, the rock-breaking depth of this method is small, and conical protrusions will be formed at the bottom of the rock, which affects the rock-breaking effect.

The third type is the straight-rotating mixed jet nozzle, that is, adding a rotating impeller with a straight hole inside the ordinary jet nozzle, which is a nozzle that organically combines ordinary straight jet flow and rotating jet flow through reasonable design. The high-pressure fluid enters the mixing chamber after passing through the rotating impeller with straight holes to form a low-speed straight-swirling mixed flow, and then pressurizes through the outlet of the nozzle to form a straight-swirling mixed jet with high axial speed and strong peripheral rotation intensity. The direct swirl mixed jet nozzle combines the advantages of straight jet and swirling jet, and can form larger hole diameter and depth. However, under the condition of confining pressure, the jet energy of straight-rotating mixed jet decays rapidly, and the rock-breaking effect is poor; at the same time, due to the complex internal structure, the pressure loss is large, and there is a swirl effect.

In addition, in recent years, some scholars have developed a pulsed cavitation porous jet nozzle, that is, by changing the internal structure of the porous nozzle, a pulsed cavitation porous jet nozzle can be formed by coupling the pulsed jet and the cavitation jet. This type of nozzle can efficiently utilize the jet energy, effectively improve the rock-breaking efficiency, and form a horizontal wellbore with a relatively large hole depth. However, under the condition of confining pressure, the jet attenuates quickly; the hole formed by it has a small diameter and irregular shape; the recoil force of the forward jet is relatively large, which is not conducive to forward drilling.

Comprehensively considering the advantages and disadvantages of the above jet nozzles, the inventor has developed a novel self-propelled rotary jet multi-hole nozzle of the present invention for the purpose of shearing and breaking rocks based on years of experience in rock crushing and nozzle development. .

Contents of the invention

The purpose of the present invention is to provide a novel self-propelled rotary jet multi-hole nozzle, especially one that can overcome the defects existing in the prior art, realize high-efficiency self-progress continuous rock breaking, form a horizontal wellbore with a certain aperture and regular shape, and achieve effective The purpose of exploiting oil and gas resources.

For this reason, the present invention has designed and developed a kind of self-propelled rotary jet nozzle. The nozzle mainly includes: the nozzle cap, the rear end shaft, the screw and so on. Its characteristics are:

The nozzle cap is a cap-shaped structure with a certain wall thickness and front and rear holes, and its front end is evenly distributed on a circle with a certain distance from the center. Multiple axes are aligned with the axis of the nozzle cap in the vertical plane where a tangent line of the circle is located. Multiple forward-facing perforations distributed at different angles (α). Since the axis of the hole is in the vertical plane where a certain tangent line of the circle is located, the projection of the axis of the hole on the front face of the nozzle cap is tangent to the circle where the high-pressure fluid passes through the nozzle cap. The jet flow has a high tangential velocity, It is beneficial to improve the rock-breaking efficiency; and because the angle between each hole and the axis of the nozzle cap is inconsistent, the formed jet acts on different areas in any cross-section of the front end of the nozzle cap, and the action areas overlap in the radial direction, but When the nozzle cap does not rotate, the forward holes do not interfere with each other. At the same time, the larger the spray distance, the larger the range of action, which is conducive to the formation of larger apertures; due to the existence of tangential velocity, the jet recoil acts on the nozzle, so that The nozzle rotates, so that the range of action of each forward hole scans along a trajectory with a certain radius, and the combined action of multiple holes completes the rock-breaking drilling. At the same time, due to the rotation of the nozzle cap, the formed holes are more regular; part of the recoil force of the forward nozzle It is used for nozzle self-rotation, which reduces the resistance of nozzle self-advancement and is conducive to the formation of deeper holes. On the outside of the nozzle cap, there are a number of backward holes that form a certain angle (β) with the axis of the nozzle cap. The rear holes mainly provide self-progressive force for the nozzle and expand the formed holes. Due to the rotation of the nozzle cap, the expanded holes are also For a more regular shape, in addition, the rear hole can be made to form a certain angle (γ) with the plane where the axis of the nozzle cap is located. When the high-pressure fluid passes, it can provide a certain torque for the nozzle cap, or increase the rotation of the nozzle cap, or restrain it. rotation. The rotation speed of the nozzle cap under certain conditions can be controlled by controlling the size and direction of the forward hole, the radius of the circle where the axis of the front face is located, and the size and direction of the rearward hole. It should be noted that the present invention requires that the rotation speed of the nozzle cap must be strictly controlled under the working condition of a certain flow rate, otherwise the rock-breaking effect will be affected. There is a small hole without thread in the center of the front end of the nozzle cap, which can be connected with the rear end shaft by a screw to realize the positioning of the nozzle cap. The inner cavity of the nozzle cap is larger than the entrance, forming a certain internal space for the jet; there is a small annular groove at the rear end of the nozzle cap, which cooperates with the rear end shaft at the rear to form a seal.

The rear end shaft is a hollow cylinder with variable diameter, and there is a small threaded hole on the front face, which can cooperate with the screw for positioning; there are multiple large diameter holes on the front hollow cylinder, which provide passages for high-pressure fluid. Its outer diameter is just enough to match the nozzle cap, extend into the nozzle cap, and combine with the nozzle cap through screws to provide support and sealing environment for the nozzle cap; there is a small annular protrusion on the end surface of the variable diameter of the rear end shaft. It cooperates with the nozzle cap to form a seal; there are threads on the rear end surface of the rear end shaft, which are mainly connected with the rear components of the assembly.

Compared with the prior art, the self-propelled rotary jet multi-hole nozzle of the present invention has advantages and characteristics:

The self-propelled rotary jet multi-hole nozzle proposed by the present invention mainly breaks rocks independently at a three-dimensional speed through a plurality of forward holes, and then jointly drills regular holes with a certain diameter in the form of orbital scanning. It mainly has the following advantages:

1. The structure is relatively simple. Especially under complex downhole conditions, the simple structure can ensure the reliability of the tool;

2. The angle between the forward hole and the nozzle axis is inconsistent, and there is a hole with a large deflection angle and a small deflection angle. The hole with a large deflection angle has the characteristics of a rotating jet, while the hole with a small deflection angle has the characteristics of a jet. The characteristics of straight jet flow, the combined action of the two can form holes with larger diameter and larger hole depth;

3. Due to the characteristics of the rotating jet, it can achieve high-efficiency rock breaking and a certain drilling speed;

4. The nozzle at the front end rotates automatically, and part of the recoil force of the forward hole is used for rotation, which reduces the self-advancing resistance and is beneficial to the extension of the hole;

5. Since all the holes are rotating, the formed holes are relatively regular.

Description of drawings

The following drawings illustrate and explain the present invention schematically, but do not limit the scope of the present invention.

Fig. 1A is a three-dimensional schematic diagram of the self-advancing rotary jet multi-hole nozzle assembly of the patent of the present invention;

Fig. 1B is a top view and A-A sectional view of the self-advancing rotary jet multi-hole nozzle assembly of the patent of the present invention;

Fig. 2A is a three-dimensional schematic diagram of the rear end shaft of the self-propelled rotary jet multi-hole nozzle of the patent of the present invention;

Fig. 2B is a top view and A-A sectional view of the rear end shaft of the self-propelled rotary jet multi-hole nozzle of the patent of the present invention;

Fig. 3A is a three-dimensional schematic diagram of the self-advancing rotary jet multi-hole nozzle nozzle cap of the patent of the present invention;

Fig. 3B is the top view of the self-propelled rotary jet multi-hole nozzle nozzle cap of the patent of the present invention;

Fig. 3C is a top view B-B sectional view of the self-propelled rotary jet multi-hole nozzle nozzle cap of the patent of the present invention;

Fig. 3D is a top view C-C sectional view of the self-propelled rotary jet multi-hole nozzle nozzle cap of the patent of the present invention;

detailed description

The self-propelled rotary jet multi-hole nozzle of the present invention mainly includes: a nozzle cap, a rear end shaft, screws and the like. It is characterized in that the front end of the nozzle cap is evenly distributed with a plurality of forward holes on a circle with a certain distance from the center, and the jet formed by the high-pressure fluid through the forward holes has a high tangential velocity, which is beneficial to rock breaking; The momentum causes the nozzle cap to rotate itself, and the orbital scanning of each hole is combined to break rocks, which is conducive to the formation of large-diameter regular holes and the self-advancement of the nozzle; there are multiple backward holes evenly distributed in the same width area on the outside of the nozzle cap. The nozzle provides self-progressive force and torque; the rear shaft is a variable-diameter hollow cylinder, the large-diameter part at the rear is used to connect the fluid pipeline, and the small-diameter part at the front cooperates with the nozzle cap to provide support for the nozzle cap and provide fluid Channels are provided; the front end surface of the front diameter part of the rear end shaft can cooperate with the screw to realize the positioning of the nozzle cap and form a rotary sealing system.

1A and 1B are schematic diagrams of the patented self-propelled rotary jet multi-hole nozzle assembly of the present invention. The structure is relatively simple, including only three components: the rear end shaft 1, the nozzle cap 2 and the screw 3, and its length can be controlled below 35mm, which is especially suitable for ultra-short radius radial horizontal well technology. The rear end shaft 1 at the rear of the nozzle is connected with the rear high-pressure hose through threads, and cooperates with the screw 3 to strictly position the nozzle cap 2. Here, the front end of the rear end shaft 1 can also be used without a threaded hole, but protruding out of the nozzle. The front end of the cap 2 has a small-diameter threaded small-diameter shaft, and the positioning of the nozzle cap 2 is realized by buckling the threaded cap at the front end of the nozzle cap 2; the nozzle cap 2 is the main functional part at the front of the nozzle, and has a certain wall thickness. The cap-shaped structure with front and rear holes has a small unthreaded hole in the center of the front face for the positioning of the nozzle cap 2; the screw 3 is also an important part, not only to bear the axial tension, but also to withstand the rotation of the nozzle cap. wear and tear, its material and processing accuracy are relatively high, but considering that the invention requires strict control of the rotation speed, that is, the rotation speed will not be too fast, this design can be accepted; the overall structure is sealed through the small gap of the labyrinth, forming a seal rotation system. The high-pressure fluid reaches the inner cavity of the nozzle cap 2 from the high-pressure hose through the rear end shaft, and a part of the fluid forms a jet with a high tangential velocity under the guidance of the nozzle cap forward hole 22, and the jet recoil acts on the nozzle cap 2 to realize For the rotation of the nozzle cap 2, the size and angle of the front and rear holes 22 can be controlled so that the rotation speed will not be too fast within a certain flow range, otherwise the rock breaking effect will be greatly reduced; , forming a reverse jet, which can expand the formed hole, and the recoil force of the jet can drive the nozzle to drag the high-pressure hose to drill continuously; in addition, the rearward hole 21 can form a certain angle with the plane where the axis of the nozzle cap 2 is located (γ), when the high-pressure fluid passes, it can provide a certain torque for the nozzle cap 2, or increase the rotation of the nozzle cap 2, or inhibit its rotation. The rotation speed of the nozzle cap 2 under certain conditions can be controlled by controlling the size and direction of the forward hole 22 , the radius of the circle where the axis of the front face is located, and the size and direction of the rearward hole 21 .

2A and 2B are schematic diagrams of the rear end shaft of the patented self-propelled rotary jet multi-hole nozzle of the present invention. From Fig. 2A, the shape of the shaft 1 at the rear end of the nozzle can be seen very vividly. It can be seen from Figure 2B that the structure of the rear end shaft 1 is relatively simple, mainly due to the change of the cylinder structure. There are threads at the rear end, which can be connected with high-pressure hoses; the small diameter part of the front end has multiple apertures evenly distributed along the circumference The slightly larger forward hole 13 has an angle θ of about 30 degrees with the center line of the rear shaft 1, which can provide a flow channel for high-pressure fluid; Cooperate with realizing the positioning of the nozzle cap 2, the front end of the rear end shaft 1 can also be used here without a threaded hole, but a small diameter shaft with a small diameter threaded on the front end of the nozzle cap 2, and the front end of the nozzle cap 2 is added Fasten the threaded cap to realize the positioning of the nozzle cap 2; there are multi-circle ring protrusions 14 on the variable-diameter end surface, which cooperate with the corresponding structure of the nozzle cap 2 to realize the labyrinth small gap seal; the internal cavities 11 and 12 are the flow of high-pressure fluid space.

3A, 3B, 3C and 3D are schematic diagrams of the self-propelled rotary jet multi-hole nozzle cap of the present invention. There is a sealing ring 24 on the rear end surface of the nozzle cap 2, and its main function is to cooperate with the rear end shaft 1 to realize rotary sealing; from Fig. 3A and the central B-B sectional view passing through the top view (Fig. 3B), it can be known that there is a ring 24 on the outside of the nozzle cap 2. 6 to 8 rear holes 21 at a certain angle (β=15° to 45°) with the axis of the nozzle cap 2, when the high-pressure fluid passes, the recoil force will be the forward thrust of the nozzle cap 2, and at the same time it can Enlarging the formed hole; it is also possible to make the rearward hole 21 form a certain angle with the plane of the axis of the nozzle cap 2 (γ=0°～30°), when the high-pressure fluid passes through, it will provide a certain torque for the nozzle cap 2, Or increase the rotation of the nozzle cap 2, or inhibit its rotation; from the cross-sectional view of a horizontal tangent line C-C passing through a circle that is a certain distance from the center in the top view (Figure 3B), it can be seen that there are 3 to 4 nozzle caps at the front end of the nozzle cap 2. On a certain circle, there are evenly distributed forward holes 22 whose central axis is in a vertical plane passing through a certain tangent of the circle, and which are distributed at different angles (α=15°～60°) to the axis of the nozzle cap, so that all The projections of the central axis of the forward hole 22 on the front end of the nozzle cap 2 are different tangents of the same circle, so all forward jets have tangential velocities, which are easier to break rocks and are conducive to efficient rock breaking. The force causes the nozzle cap 2 to rotate on its own. Due to the rotation of the nozzle cap, the holes formed by the jet flow are more regular, and the jet recoil force is reduced at the same time, which is beneficial to the self-advancement of the nozzle and continuous rock-breaking drilling; through the design of multiple forward holes 22 The angle with the central axis of the nozzle cap 2 (α=15°～60°) makes each forward hole 22 act in a small circle at different radii from the jet center, and the active area between different holes is in the radial direction There is superimposition, and through the rotation of the nozzle cap 2, the scanning type large-area continuous rock breaking is realized; the selection of the circle where the front end face of the forward nozzle 22 needs to comprehensively consider the following factors: the wall thickness of the front face of the nozzle cap, the axis of the forward hole and the nozzle The angle between the hole axis (α), the size of the forward hole, the size of the jet action area, the size of the center hole on the end face of the nozzle cap, the strength of the front face of the nozzle cap after perforation, and the torque provided by the forward jet are recommended. Larger; there is an unthreaded center hole 23 on the front end of the nozzle cap 2, the main function is to cooperate with the screw 3, or cooperate with the rear end shaft 1 to realize the axial positioning of the nozzle cap, and at the same time realize the overall sealing of the system through a small gap; The cavity 26 is a flow space for high-pressure fluid.

The above descriptions are only illustrative specific implementations of the present invention, and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention are all acceptable. Should belong to the protection scope of the present invention. And it should be noted that each component of the present invention is not limited to the above-mentioned overall application, and each technical feature described in the description of the present invention can be selected to be used alone or in combination according to actual needs, so the present invention is of course Other combinations and specific applications related to the invention of this case are covered.

Claims (10)

1. a self-advancing type rotating jet jet rose, mainly comprises: cap of spraying nozzle, rear end axle, screw, it is characterized in that, cap of spraying nozzle front end fromOpen center certain distance certain circle on be uniform-distribution with multiple forward direction eyelets, high-pressure fluid through forward direction eyelet form jet there is very high tangential speedDegree, is beneficial to brokenly rock; Jetflush power makes cap of spraying nozzle rotation simultaneously, each eyelet track scanning formula combined-breaking rock, and major diameter rule hole is conducive to be shapedEye, is also conducive to nozzle from entering; Cap of spraying nozzle outside is uniform-distribution with multiple rear to eyelet in the region of same width, and can be nozzle provides from entering power,Moment of torsion also can be provided; Rear end axle is for straightening footpath hollow circular cylinder, and rear portion major diameter part is used for connecting fluid line, anterior small diameter portion and nozzleCap coordinates, for cap of spraying nozzle provides support, for fluid provides passage; Rear end axle front straight path portion front end face can with screw fit, realize cap of spraying nozzle fixedPosition, forms a rotary sealing system.

2. self-advancing type rotating jet jet rose as claimed in claim 1, is characterized in that, cap of spraying nozzle front end is leaving certain of center certain distanceThe multiple forward direction eyelets that are uniform-distribution with on circle, its axis through this circle a certain tangent line vertical plane in, and with nozzle-axis at an angle,Therefore, eyelet axis is tangent at projection and this circle of cap of spraying nozzle front end face, and jet exit velocity has very high tangential velocity, is conducive to improve brokenRock efficiency; Due to the existence of tangential velocity, jetflush masterpiece, for nozzle, makes nozzle generation rotation, makes the sphere of action edge of each forward direction eyeletThe track scanning of certain radius, porous synergy completes rock-breaking drilling, simultaneously because the rotation of cap of spraying nozzle makes the eyelet of formation more regular;A recoil strength part for forward direction nozzle, for nozzle rotation, has reduced nozzle from the resistance entering, and is conducive to form darker eyelet.

3. self-advancing type rotating jet jet rose as claimed in claim 2, is characterized in that, cap of spraying nozzle front end is leaving certain of center certain distanceThe multiple forward direction eyelets of the axis being uniform-distribution with on circle in the vertical plane of a certain tangent line of this circle, its axis in vertical plane with nozzle shaft wire clampAngle (α) difference, therefore the jet forming acts on different regions in the arbitrary section of cap of spraying nozzle front end, its zone of action exists diametricallyStack, but in the non-rotary situation of cap of spraying nozzle, each forward direction eyelet does not interfere with each other, spray is apart from larger within the specific limits simultaneously, and sphere of action is also larger,Be conducive to form larger aperture.

4. self-advancing type rotating jet jet rose as claimed in claim 3, is characterized in that, cap of spraying nozzle front end is leaving certain of center certain distanceThe multiple forward direction eyelets that are uniform-distribution with on circle, wherein round selection need to consider following factor: the wall thickness of cap of spraying nozzle front end face, forward direction eyeletThe size in axis and nozzle bore eye axis angle (α), forward direction barrel hole size, jet action region, cap of spraying nozzle end-face central hole size, cap of spraying nozzleIntensity, the factors such as moment of torsion that provide after front end face punching, suggestion is as far as possible large in the situation that allowing.

5. self-advancing type rotating jet jet rose as claimed in claim 1, is characterized in that, nozzle outside is uniformly distributed in the region of same widthMultiple backward eyelets, its axis and nozzle-axis (β) at an angle, being mainly nozzle provides from entering power and expanding established eyelet,Due to the rotation of cap of spraying nozzle, the eyelet expanding is similarly the comparatively shape of rule, in addition, makes backward eyelet become certain with cap of spraying nozzle axis place planeAngle (γ), when high-pressure fluid is through out-of-date, will provide certain moment of torsion for cap of spraying nozzle, or increases cap of spraying nozzle rotation, or suppresses its rotation.

6. self-advancing type rotating jet jet rose as claimed in claim 1, is characterized in that, axle anterior small diameter portion external diameter in rear end designs lucky energyEnough match with cap of spraying nozzle, for cap of spraying nozzle provides support; Exist thereon distribute along surface uniform be multiple eyelets of angle θ with rear end axle axis,For high-pressure fluid provides passage.

7. self-advancing type rotating jet jet rose as claimed in claim 6, is characterized in that, straightens on the end face of footpath and exists multi-turn annulus protruding at rear end axleRise, correspondingly on cap of spraying nozzle rear end face, have multi-turn ring groove, in the time that rear end axle coordinates with cap of spraying nozzle, realize the little clearance seal of labyrinth type.

8. self-advancing type rotating jet jet rose as claimed in claim 1, is characterized in that, has an aperture at cap of spraying nozzle front end face center,And there is a threaded apertures at axle front end face center, rear end, in the time that rear end axle coordinates with cap of spraying nozzle, can cap of spraying nozzle be navigated to rear end axle by screwUpper, realize sealing by little gap simultaneously, form a rotary sealing system.

9. self-advancing type rotating jet jet rose as described in claim 1 to 4 any one, is characterized in that, leaves center certain at cap of spraying nozzle front endOn certain circle of distance, be uniform-distribution with 3～4 axis and be different angles (α) point with cap of spraying nozzle axis in the process vertical plane of this circle tangent lineMultiple forward direction eyelets of cloth, angle is between 15～60 degree.

10. self-advancing type rotating jet jet rose as described in claim 1 or 5 any one, is characterized in that, nozzle outside is in the district of same widthIn territory, be uniform-distribution with 6～8 backward eyelets, provide from entering power, its axis and nozzle-axis (β) at an angle, angle is 15～45Between degree; Make backward eyelet and cap of spraying nozzle axis place plane angled (γ), moment of torsion is provided, angle is between 0～30 degree.