46 results about "Maximum diameter" patented technology

This application discloses an insulated torsion bar spline, comprising a straight section, a recessed section, a tapered section, and a bottom section arranged sequentially from top to bottom. The maximum diameter of the recessed section, tapered section, and bottom section is less than or equal to the diameter of the straight section. The total height of the insulated torsion bar spline is defined as L, the height of the straight section as L1, the height of the recessed section as L2, the height of the tapered section as L3, and the height of the bottom section as L4, satisfying the following conditions: 10%L≤L1≤15%L, 38%L≤L2≤43%L, 45%L≤L3≤49%L, and L4≤1%L. The diameter of the straight section is defined as D, and the maximum depth of the recessed section is 2%~4%D. The insulated torsion bar spline is made of metal, and the straight section, recessed section, tapered section, and bottom section are connected as a single structure. This application's insulated torsion bar spline, through optimization of its shape and dimensions, effectively improves the torque of the insulated torsion bar.

This invention discloses a method, apparatus, equipment, and storage medium for detecting annular flow pressure drop in wellbore. The method includes: fitting acquired electrical logging data of the well diameter of the target well; processing an irregularly enlarged well section into a concave arc-shaped wellbore to be tested; obtaining the maximum diameter and concave height of the concave arc-shaped wellbore; determining the diameter enlargement factor of the concave arc-shaped wellbore based on the maximum diameter and the pre-acquired drill bit diameter of the target well; and inputting the diameter enlargement factor, the concave height, and the drilling data of the target well into a pre-constructed model of an irregular wellbore annular flow pressure drop in a reference well for calculation to obtain the annular flow pressure drop of the target well. This method enables rapid detection of the annular flow pressure drop of the target well based on the annular flow pressure drop of the reference well, improving the detection efficiency of annular flow pressure drop in irregular wellbore annulus.

This utility model discloses a floating material trough structure and a buffer paper pad winding device for winding buffer paper pads. The floating material trough structure includes a material trough, a rotating shaft, a limiting plate, a driving mechanism, and a resetting component. The end of the material trough is provided with a flange, allowing the material trough to swing from a horizontal state to a non-horizontal state. The driving mechanism drives the limiting plate to swing around the rotating shaft as the swing center. The resetting component ensures that the material trough maintains a tendency to swing from a non-horizontal state to a horizontal state. The buffer paper pad winding device includes a winding mechanism and the floating material trough structure. With this utility model's floating material trough structure, regardless of whether the wound buffer paper pad roll has the minimum or maximum diameter, the material trough remains tightly attached to the outer periphery of the buffer paper pad roll, ensuring adequate tightness. The diameter of the buffer paper pad roll wound by the buffer paper pad winding device can vary between the minimum and maximum diameters, and it ensures that the tape is firmly adhered and wrapped around the outer periphery of the buffer paper pad roll, preventing the buffer paper pad roll from unraveling.

A polyester-resin-coated seamless can including a reduced diameter portion obtained by neck processing within a distance of 0% to 15% from a can body uppermost portion with respect to a total height of the can from the can body uppermost portion to a can bottom of the can. A ratio Im / Iu is 1.0 or more, where Iu (cps / μm) is calculated by dividing a maximum peak intensity in a range satisfying 15°≤2Θ≤19° of an outer-surface coating in a maximum reduced diameter portion of the reduced diameter portion by a thickness of the coating at the measurement site, and Im (cps / μm) is calculated by dividing a maximum peak intensity in a range satisfying 15°≤2Θ≤19° of outer-surface coating at a measurement site within a distance of 45% to 60% from the can body uppermost portion by a thickness of the outer-surface coating at the measurement site.

The invention provides a grinding method for a roller and a grinding machine, and relates to the technical field of machining. The grinding method for the roller comprises the following steps that a groove is formed in the roller face of the end of the roller to be machined, and a first roller is obtained; acquiring a surface profile curve of the first roller; based on grinding treatment parameters, grinding treatment is conducted on the first roller, and a second roller is obtained; wherein the grinding treatment parameters comprise grinding current, and the grinding current is used for representing the maximum limiting current determined on the basis of the surface profile curve. The grooves are formed in the roller surface of the end of the roller, the maximum diameter change value of the surface of the roller is increased, the surface profile curve of the roller is made to change, then the grinding machine control system improves the maximum limiting current set value, traditional grinding current limitation is broken through, the grinding process can be stably operated under the higher current condition, and the grinding efficiency is improved. The material removal efficiency is improved; and the processing time is shortened.

The present invention relates to a drill bit and a method of manufacturing a perforated article. In the case where the rigidity of the main shaft of a perforating machine is sufficient, it goes without saying, but even in the case where perforation is performed using a hand-held tool rotation device or the rigidity of the main shaft of the perforating machine is low, a workpiece composed of a composite material or a metal or the like can be perforated with high accuracy. The drill bit of the embodiment has a first cutting edge formed on the leading end side in such a manner that the leading end angle is continuously or discontinuously reduced from the leading end side to the trailing end side, and on the other hand, the clearance angle is continuously or discontinuously reduced from the leading end side to the trailing end side, and is used to perforate a workpiece to form a pilot hole; a second cutting edge formed by being positioned away from the first cutting edge toward the trailing end side, and used to perform finishing of the pilot hole, and having a clearance angle at the maximum diameter position; and a vibration-damping portion formed between the first cutting edge and the second cutting edge, and reducing vibration of the second cutting edge by being inserted into the pilot hole processed by the first cutting edge.

Aspects of the disclosure relate to a package, a carrier (90) for packaging one or more articles (B, B1, B2) and a blank (10; 110; 210; 310A, 310B) for forming the carrier. The package comprises an article carrier and one or more articles. The carrier comprises a main panel (14) having at least two article retention structures for receiving and securing the main panel to a respective article. Each of the at least two article retention structures comprises a center. The center C of the at least two article retention structures is spaced apart from the center of an adjacent one of the at least two article retention structures by a distance. The distance is greater than the maximum diameter of each of the at least two articles.

The utility model relates to a novel blank punching tool which comprises a die body, a forming cavity and a limiting cavity which sequentially extend in the vertical direction are formed in the middle of the die body, and the forming cavity is communicated with the limiting cavity. The base assembly comprises a leakage plate pad and an insert, the leakage plate pad is embedded in the limiting cavity, a first through hole extending in the vertical direction is formed in the middle of the leakage plate pad, a limiting part is formed in the position, located at the top end of the first through hole, of the leakage plate pad, the insert abuts against the limiting part, and a second through hole extending in the vertical direction is formed in the middle of the insert; the maximum diameter of the second through hole is smaller than or equal to the minimum diameter of the first through hole; and the outer peripheral surface of the punch assembly can be connected with the hole wall of the second through hole in a sliding manner. The utility model provides a novel blank punching tool with high efficiency and high yield through the die body, the drain plate, the insert and the punch assembly, and the novel blank punching tool has the advantages of good interchangeability, reduction of the cost of forgings and guarantee of the product quality.

A cylindrical side-wall core is acquired from an inner circumferential surface of a well at a predetermined depth from a ground surface. First, second and third measurement cross sections spaced apart in a longitudinal direction of the core are set. In each cross section, the length of the maximum diameter of the cross section where the amount of distortion relative to the diameter of a standard circle is largest and the length of the minimum diameter where the amount of distortion relative to the diameter of the standard circle is smallest are measured. Six independent components among stress tensors for defining three-dimensional stress elements are obtained using an equation representing a difference between maximum and minimum stresses acting on the side-wall core along each cross section and another equation representing the angle between the well excavation direction and the action direction of the maximum stress on each cross section.

The extrusion equipment for SPC floor production comprises a machine barrel, a pair of conical screws with opposite rotating directions, a driving device in transmission connection with the pair of conical screws and a confluence core installed at a discharging port of the machine barrel, and each conical screw comprises a conical rod body extending from front to back and a thread spirally extending around the conical rod body; the bottom diameter of the conical rod body is gradually reduced from front to back, the outer diameter of the threads is gradually reduced from front to back, the maximum diameter of the conical screw rod is 200-250 mm, and the minimum diameter of the conical screw rod is 100-150 mm; the conical rod body is sequentially provided with a feeding section, a first mixing section, a second mixing section, a first metering section, an exhaust section and a second metering section from front to back, the threads are double-end threads on the feeding section, the first mixing section and the second mixing section, the threads are single-end threads on the first metering section, the threads are four-end threads on the exhaust section, and the threads are three-end threads on the second metering section; the extrusion device can efficiently and stably extrude materials in a low-consumption and high-quality mode, and is particularly suitable for production of SPC plates.

The invention belongs to the field of abrasive grinding tools, and particularly relates to a wafer thinning grinding wheel and a preparation method thereof.The wafer thinning grinding wheel comprises a base plate 1, an abrasive coating 11 is fixed to the end face of the base plate 1, abrasive particles are arranged in the abrasive coating 11, and the abrasive particles comprise first abrasive particles 12 located at the bottom of the abrasive coating 11 and close to the end face of the base plate 1; the abrasive material further comprises second abrasive particles 13 arranged in a layer above the first abrasive particles 12, the average diameter of the first abrasive particles 12 is 110%-140% of the diameter of the second abrasive particles 13, and the minimum diameter of the first abrasive particles 12 is not lower than 70% of the maximum diameter.

The utility model discloses a special-shaped drill bit, which relates to the technical field of construction drilling equipment, can be arranged in a pile casing in a penetrating manner, and structurally comprises a sleeve, one end of the sleeve is used for being connected with a drill rod, and the other end of the sleeve is provided with a slag outlet; the special-shaped protective ring is fixedly arranged on the outer side of the sleeve in a sleeving mode, one side of the special-shaped protective ring is of an inwards-concave structure, and the maximum diameter of the special-shaped protective ring is smaller than the inner diameter of the protective cylinder. And the conical cutting edge is obliquely connected between the inner side of the special-shaped retainer and the side wall of the sleeve. According to the special-shaped drill bit, the drill bit can smoothly pass through a deformation area of a pile casing, the diameter of a follow-up drill hole meets the requirement, cost is low, and safety is high.

To solve the problem that a handle grip of a spinning reel is easily damaged when the spinning reel is placed on a floor surface, etc., and its appearance and commercial value are lowered. Further, the handle grip is often made of metal, resin, or the like, and is slippery, so that a fish caught during fishing may be missed. To improve the touch of a handle grip and enable comfortable fishing.SOLUTION: A hollow handle grip cover made of an elastic material having a hole at the approximate center of each hemispherical part when an approximately spherical thin-walled handle grip cover is assumed to be divided into two hemispherical parts, and at least one of the holes is extended to a size capable of passing the maximum diameter part of the handle grip without damaging it, is freely exchangeably put on and mounted. The spinning reel to which the handle grip cover is previously attached in a production stage, etc., is made available to a purchaser.SELECTED DRAWING: Figure 1

Device (10) for holding a component (20) to be encased in plastic, wherein the device (10) has a retaining element (11) for generating a releasable mechanical positive connection with a fastening area (21) of the component (20), characterized in that the retaining element (11) has a plug-and-turn locking element (12), wherein the retaining element (11) has a mandrel (13) extending along an axial direction (100), wherein the mandrel (13) has a cylindrical first sub-section (13') and a cuboid second sub-section (13''), wherein the maximum diameter of the second sub-section (13'') is smaller than the maximum diameter of the first sub-section (13'), and wherein the plug-and-turn locking element (12) is formed in an end region of the second sub-section (13'') and comprises at least one positive locking element (14),wherein at least one positive locking element (14) projects from the mandrel (13) along a transverse direction (101) perpendicular to the axial direction (100) of the mandrel (13).

The utility model discloses a ceramic fiber tube forming die which comprises two groups of die bodies, a first connecting block and a second connecting block are respectively fixed on two sides of the die bodies. Compared with the prior art, due to the split type mold body structural design, the risk of structural damage during demolding of the ceramic fiber pipe is remarkably reduced, the first connecting block and the second connecting block arranged on the two sides of the mold body are accurately engaged through a step structure and anti-skid lines and are matched with the first bolt for locking, and the sealing performance and stability of the forming cavity are ensured; the mold core is of a gradually-changed taper structure, the maximum-diameter end is fixed to the connecting flange, contact resistance between a fiber pipe and the mold core during demolding is effectively reduced, the pressure relief opening releases redundant gas in the initial forming stage to avoid the bubble defect, the supporting spring pushes the sealing plate to close the air hole to maintain forming pressure in the later stage, and the rejection rate is greatly reduced; and meanwhile, the split type die body design simplifies the die maintenance process, and the production cost is reduced.

The present invention addresses the problem of providing a vacuum suction pad capable of reliable and stable suction regardless of the shape and orientation of an egg. As the means for solving the problem, the present invention is a vacuum suction pad (10) that suctions a prescribed egg (E), is formed in a cylindrical shape, and can expand and contract along the direction of an axis (12) of the cylindrical shape. The vacuum suction pad comprises: a first contact part (16) that is formed as an opening (14) and has a first tapered shape; a second contact part (18) that is formed closer to an intake side than the first contact part (16) and has a second tapered shape; and a first bellows part (20) that is formed between the first contact part and the second contact part and protrudes outward. The maximum diameter (X1) of the first contact part (16) is 0.6-1.2 times the lateral dimension of the egg (E), the maximum diameter (X3) of the second contact part (18) is smaller than the minimum diameter (X2) of the first contact part (16) and 0.3-0.7 times the lateral dimension of the egg (E), and the egg (E) is suctioned by the first contact part (16) and the second contact part (18).

The objective is to provide a thermally conductive sheet that offers superior insulation properties in addition to thermal conductivity. [Solution] The material comprises a reinforcing material and a resin layer laminated on the front and back surfaces of the reinforcing material, wherein the resin layer contains resin and agglomerated boron nitride, and in particles of the agglomerated boron nitride with an area circle equivalent diameter in the range of 20 to 100 μm, the codispersion between the area circle equivalent diameter and the maximum Ferret diameter is 275 μm. 2 The following is a heat dissipation sheet.

The invention relates to a print head (10) for a 3D printer (1), comprising a feed zone (11) with a feeder (12) for a starting material (21) with variable viscosity, a plasticizing zone (14) with a heater (15) and an outlet opening (16) for the liquid phase (22) of the starting material (21), and a conveying device (30) for conveying the starting material (21) from the feed zone (11) to the plasticizing zone (14), wherein the conveying device (30) comprises a piston (31) that can be inserted into the feed zone (11), wherein the piston (31) has a first piston section (5) facing the plasticizing zone (14) with a guide surface (9) through which the piston (31) is guided in a recess (7) of the print head (10), wherein the piston (31) is connected by a positive locking connection of the first piston section (5) is secured against radial rotation by the recess (7) of the printhead (10). It is characterized by the fact that the first piston section (5) and the recess (7) of the print head (10) form a cross-sectional area (F), wherein a maximum diameter (d1) of the cross-sectional area (F) is formed by a circle (2) and the cross-sectional area (F) has rotationally symmetric circular segment-shaped recesses (3).

The spark plug of the present application is one in which, in a mirror-polished surface obtained by mirror polishing a cut surface obtained by cutting the insulator in a direction perpendicular to the axial direction at a position 2 mm away from the maximum diameter portion of the enlarged diameter portion toward the rear end side, in a case where 20 first observation regions of 192 μm x 255 μm are set so as to overlap with a reference position, which is a position 0.2 mm away in the radial direction from the inner peripheral surface side of the insulator, and not to overlap with each other, the proportion of the area of all the air holes included in the mirror-polished surface with respect to the total area is 3.5% or less, and in a thermal-etched surface obtained by subjecting the mirror-polished surface to thermal etching, in a case where 20 second observation regions of 32 μm x 43 μm are set so as to overlap with the reference position and not to overlap with each other, when the particle size distribution of the alumina particles included therein is assumed to be a normal distribution and the average particle diameter is assumed to be A and the standard deviation of the particle diameter is assumed to be σ, A is 1.9 μm or more and 2.8 μm or less, and A + 3σ is 3.0 μm or less.

The invention relates to the technical field of toys, and provides a splicing structure suitable for a doll, the doll, a mold and a machining method. A notch is formed in a part of the opening of the ball socket, and the notch extends in the radial direction of the opening of the ball socket to form a depth; the inner diameter of the opening of the ball socket at the non-notch position is smaller than the maximum diameter of the ball head; and the gap allows the ball socket opening to expand outwards and deform elastically, so that the ball head can be pulled out of and / or pulled out of the ball socket. The requirements for increasing the rotating force and reducing the insertion and extraction force are considered at the same time, the problem of contradiction between the insertion and extraction force and the stability caused by ball socket machining is solved, the structure is simple, and the practicability is high.

The utility model discloses a kind of automatic magnetic core unloading devices, including conveyor belt and the material taking mechanism, cooling mechanism, pusher mechanism and material collecting mechanism sequentially arranged along conveying direction, pusher mechanism and material collecting mechanism are separately arranged at the both sides of conveyor belt and oppositely arranged;The both sides of the section of conveyor belt close to material taking mechanism are provided with limit plate, the passage that can be formed for magnetic core passes between two limit plates, the width of passage is equal to the maximum diameter of magnetic core;Pusher mechanism includes first support, first cylinder, pusher plate, second cylinder, front baffle, and the end of front pusher plate away from material taking mechanism is provided with rear baffle;Material collecting mechanism includes third cylinder and the material collecting table on the output end of third cylinder, and material collecting table is used to place material collecting plate, third cylinder drives material collecting table to move in longitudinal direction to make material collecting plate on material collecting table and conveyor belt be in same horizontal plane.

A steel sheet includes a predetermined composition, in which a microstructure at a position 1 / 4 of the thickness from a surface in the direction of the sheet thickness includes, in % by volume, ferrite: 80% or more, martensite: 2% or less and residual austenite: 2% or less, a proportion of non-recrystallized ferrite in the ferrite of 5% or less, and in the microstructure of the steel sheet drawn by 10% at the position 1 / 4 of the thickness from the surface in the direction of the sheet thickness, a numerical density of the voids having a maximum diameter of 1.0 µm or more is 1.0 × 109 pieces / m2 or less.

A forging hammer machine comprises a forging hammer assembly, a feeding assembly and a rack, the forging hammer assembly and the feeding assembly are both arranged on the rack, and the feeding assembly is located on one side of the forging hammer assembly and used for combining a platinum ring arranged on a rubber tube in a sleeving mode with a rubber tube hammer; wherein the forging hammer assembly is provided with a plurality of hammer blocks, at least two hammer blocks are provided with arc-shaped holes allowing the rubber tube to penetrate through, at least part of the diameter of each arc-shaped hole is gradually decreased in the direction away from the feeding assembly, and the ratio of the maximum diameter of each arc-shaped hole to the minimum diameter of each arc-shaped hole is larger than or equal to 0.15. And less than or equal to 0.2.

The utility model relates to a novel punch which comprises a main body part, a first forming part and a second forming part, the first forming part is arranged below the main body part, the second forming part is arranged below the first forming part, and the main body part, the first forming part and the second forming part are sequentially connected in a smooth transition mode in the vertical direction. The radius of the second forming part is gradually reduced from top to bottom along the central shaft; wherein the maximum diameter of the first forming part is larger than the maximum diameter of the main body part, and the maximum diameter of the first forming part is larger than the maximum diameter of the second forming part. In this way, the problems that after an existing punch deviates, the attaching degree of the punch and the inner side of a die is tighter, abrasion is aggravated, and the service life of the punch and the service life of the die are shortened are solved.

This utility model relates to the field of inspection fixtures for machined parts, specifically to an inspection component for annular grooves inside small-diameter deep holes. It consists of a split-type positioning sleeve and a measuring pin. The split-type positioning sleeve includes a cylindrical body, which is a cylindrical tube with symmetrically cut axial planes on both sides. The cylindrical body is divided into two symmetrically arranged positioning plates, each with an arc-shaped cross-section. The lower outer surface of each positioning plate is surrounded by a measuring step that matches the annular groove. The measuring pin has two cylindrical pins, one end being a through end and the other a stop end. The through end corresponds to the minimum diameter required for the annular groove, and the stop end corresponds to the maximum diameter required for the annular groove. This utility model, through the combination of the split-type positioning sleeve and the measuring pin, achieves rapid and accurate detection of the diameter of annular grooves inside small-diameter deep holes.

Provided is a measuring cap that can be easily rotated without causing pain and that can contribute to a reduction in the amount of resin. The measuring cap has a measuring cylinder portion and a fitting portion, the measuring cylinder portion has a cylindrical portion that extends in the circumferential direction, and two finger hooking wall portions that are located on one end side compared to the fitting portion and extend from the outer peripheral surface of the cylindrical portion to the radially outer side, the two finger hooking wall portions have side surfaces that extend from the outer peripheral surface of the cylindrical portion to the radially outer side when viewed from the central axis direction, and outer surfaces that extend in the circumferential direction when viewed from the central axis direction and connect the end portions of the radially outer sides of the side surfaces to each other, when the smaller of the intersection angles of a tangent line that is tangent to the circumferential center of the outer surface and the side surface when viewed from the central axis direction is set as θ, the width of the circumferential direction of the finger hooking wall portion is set as W, and the maximum diameter of the cylindrical portion is set as A, W / A < 0.9, when 0.13 ≤ W / A, θ ≤ 90°, and when W / A < 0.13, θ ≤ 60°.

To provide a constant velocity universal joint with a cover member (back cover) that allows for installation without a backup ring and without the sealing material (O-ring) getting caught. [Solution] This is a constant velocity universal joint in which a cover member mounting portion is formed on the inner circumferential surface of the outer joint member. The cover member has an inner circumferential surface into which it is fitted, and has a tapered shape that widens in diameter from the inner side in the joint axial direction to the outer side in the joint axial direction. A retaining ring mounting portion for fitting a retaining ring is provided on the outer side in the joint axial direction of the outer joint member, which is further than the cover member mounting portion, and an entrance portion for guiding the cover member for fitting the cover member into the cover member mounting portion is provided on the outer side in the joint axial direction of the retaining ring mounting portion. When the minimum diameter of the entrance portion is Dc, the maximum diameter of the cover member is Db, and the outer diameter dimension of the elastic seal ring when mounted on the cover member is Da, Da

The utility model discloses a pen holding device suitable for pens with different diameters, which comprises a soft sleeve body, a support part and a containing cavity, the soft sleeve body and the support part are integrally formed by elastic soft materials, the pen holding device is suitable for the pens with different diameters through the structure and the material property of the support part, and the problems that the pen holding device is relatively single and the pen holding device is inconvenient are solved. A single pen holding device can only be matched with a pen with a diameter of one specification; according to the pen holder, the supporting part comprises the supporting rib and the rib extrusion cavity, expansion and fixation of the pen holder after the pen holder enters the containing cavity are achieved through cooperation of the supporting rib and the rib extrusion cavity and the structure of the supporting rib, and the maximum diameter D2 and the minimum diameter D1 suitable for the pen holder are divided through the extrusion degree of the supporting rib; when the supporting part is in a completely natural state, the diameter of the pen holder is the minimum diameter allowing the pen holder to penetrate through the supporting part; and when the supporting part is in a complete extrusion state, the diameter of the pen holder is the maximum diameter allowing the pen holder to penetrate through the containing cavity.

The utility model discloses a drill rod fishing tool, which is used for fishing a broken drill rod and comprises a joint, the inner cone is connected with the connector and is of a cylindrical body structure; the inner cone can rotate around a fixed point of the joint I; the guide sleeve is connected with the inner cone and is of a columnar structure; the guide sleeve can rotate along with the inner cone; a conical inner hole is formed in the inner cone in the axis direction of the inner cone, and the hole diameter of the conical inner hole is sequentially increased in the direction from the connector to the guide sleeve. The maximum hole diameter of the conical inner hole is larger than the outer diameter of the broken drill rod; the inner diameter of the guide sleeve is larger than the outer diameter of the broken drill rod. The fishing tool is simple in structure and suitable for fishing under special conditions, for example, a broken drill rod is in an inclined state.

The application discloses an ejector structure with self-adaptive nozzle area adjustment, and belongs to the technical field of ejectors.The ejector structure comprises an ejector shell, the ejector shell is internally provided with a primary flow channel, a secondary flow channel and a collecting cavity, the primary flow channel is communicated with the collecting cavity; a nozzle is installed in the collecting cavity, the nozzle is located above the secondary flow channel, the nozzle is internally provided with an elastic telescopic ejector pin, a distal end of the nozzle is an outlet part, a cross section of the outlet part is a rectangle, the ejector pin is provided with a pin body part and a distal end pin tip part, the diameter of the pin tip part gradually decreases from the proximal end to the distal end, the pin tip part slides in the outlet part, the maximum diameter of the pin tip part is smaller than the inner diameter of the outlet part, and the outer diameter of the pin body part is larger than the inner diameter of the outlet part.The ejector structure with self-adaptive nozzle area adjustment solves the problem that the existing nozzle has a fixed cross section, the throat area is constant, and the working condition adaptability is poor.