CN209260116U - It is a kind of that the more taper oxygen rifles for scraping slag are accurately positioned - Google Patents

Abstract

The utility model discloses more taper oxygen rifles that slag is scraped in a kind of accurate positionin, belong to pneumatic steelmaking and smelt oxygen rifle technical field, for solving the problems, such as that existing more taper oxygen rifle outer wall steel slag cleanings are inconvenient.The oxygen therapy pipeline of the utility model is arranged with lower supporting plate, lifting platform is provided with above lower supporting plate, lifting platform is provided with lifting drive, lifting platform is connected with lifter plate, through-hole is offered in the middle part of lifter plate, rotating ring is provided in through-hole, rotating ring is located at the lower section of oxygen rifle ontology, rotating ring inner wall is provided with the retractable of multiple annular spreads and scrapes slag unit, the outer wall of rotating ring offers the tooth of several annular spreads, tooth engagement has at least one rotation drive device, the upper and lower ends of rotating ring are provided with positioning ring, the outer diameter of positioning ring is greater than the outer diameter of rotating ring, the inner wall of through-hole offers the placing groove of the annular convenient for placement positioning ring, placing groove and through-hole are interconnected.

Description

It is a kind of that the more taper oxygen rifles for scraping slag are accurately positioned

Technical field

The utility model relates to pneumatic steelmakings with oxygen rifle technical field is smelted, and scrape more particularly to a kind of accurate positionin More taper oxygen rifles of slag.

Background technique

Oxygen rifle is one of capital equipment of pneumatic steelmaking, when it is responsible for blowing into furnace after bath lancing and finishing blowing Into furnace, molten bath nitrogen flushing carries out slag splashing to protect the task of furnace lining.Oxygen rifle is inevitable during blowing and slag splashing Ground can adhere to steel slag in oxygen rifle, if cannot in time remove steel slag, with the increase of smelting furnace number, often splashing primary slag will Slag blanket in the oxygen rifle of dry slag increases by 3~5mm causes oxygen rifle dry slag more and more thick, at this time as " snowball " Oxygen rifle cannot normally go up and down operation, i.e., cannot propose oxygen rifle oral area position, at this moment can only cut the oxygen rifle of dry slag with flame Cutter is cut off, and splits out the oxygen rifle cut off, and is replaced oxygen rifle, is greatly reduced so as to cause the service life of oxygen rifle, and oxygen is increased Rifle cost depletions, and need frequent burning torch, change rifle, the continuity of pneumatic steelmaking production is destroyed when serious, increases the labor of worker Fatigue resistance.

The mode of part oxygen rifle cleaning steel slag are as follows: stop pneumatic steelmaking, by manually individually being cleared up, while oxygen rifle table Face temperature is high, is easy to appear security risk during worker operation, just carries out if oxygen rifle surface temperature is dropped to normal temperature state Slag is scraped, steel slag is caused to condense, cleaning difficulty increases, and cleaning work low efficiency, clearance time is long, influences the normal of pneumatic steelmaking Work.

The internal diameter that existing slag scraper hangs knife is immutable, and for more taper oxygen rifles, the outer diameter gradual change of oxygen rifle ontology cannot It is well adapted for the outside of more taper oxygen rifles, during scraping slag, the small position of outer diameter, which exists, scrapes slag dead angle, cannot be to oxygen rifle sheet External wall is thoroughly cleared up；Oxygen rifle ontology is vacantly arranged, and existing slag scraper is required to relocate before scraping slag every time, Working efficiency is low.

Utility model content

The purpose of this utility model is that: in order to solve the problems, such as that existing more taper oxygen rifle outer wall steel slag cleanings are inconvenient, The utility model provides a kind of more taper oxygen rifles for being accurately positioned and scraping slag.It is intended that providing a kind of included positioning slag-scraper More taper oxygen rifles the outer wall of more taper oxygen rifles is thoroughly cleared up with adapting to the oxygen rifle outer wall of outer diameter gradual change.

The utility model specifically uses following technical scheme to achieve the goals above:

More taper oxygen rifles of slag are scraped in the accurate positionin of the utility model, including oxygen rifle ontology, oxygen rifle ontology are connected with oxygen therapy Pipeline, oxygen rifle ontology are connected with water inlet pipe and return pipe；Oxygen therapy pipeline is arranged with lower supporting plate, is provided with above lower supporting plate Lifting platform, lifting platform are provided with lifting drive, and lifting platform is connected with lifter plate, offers through-hole, through-hole in the middle part of lifter plate It is inside provided with rotating ring, rotating ring is located at the lower section of oxygen rifle ontology, and rotating ring inner wall is provided with the flexible of multiple annular spreads Scrape slag unit, the outer wall of rotating ring offers the tooth of several annular spreads, and tooth engagement has at least one rotation drive device, rotation The upper and lower ends of change are provided with positioning ring, and the outer diameter of positioning ring is greater than the outer diameter of rotating ring, and the inner wall of through-hole offers just In the placing groove of the annular of placement positioning ring, placing groove and through-hole are interconnected.

The utility model is as it is further preferred that oxygen therapy pipeline is also arranged with the upper support above lower supporting plate Plate is provided with multiple guide posts between upper backup pad and lower limbs support pad, multiple guide posts run through lifting platform, and lifting drive is The upper end of lower supporting plate is arranged in hydraulic cylinder, hydraulic cylinder, and the telescopic shaft of hydraulic cylinder and the lower end of lifting platform are connected with each other.

The utility model is used as it is further preferred that scraping slag unit includes positioning column, limited block, the first block, second gear Block, positioning sleeve, compressed spring, arc panel and dreg scraper knife；One end of positioning sleeve and the inner wall of rotating ring are connected with each other, positioning sleeve The other end is hanging and is connected with the first block, and the side of dreg scraper knife and arc panel is connected with each other, the other side of arc panel and positioning Column is connected with each other, and the other end of positioning column is connected with limited block after protruding into positioning sleeve, and positioning column is arranged far from one end of limited block There is the second block, compressed spring is arranged on positioning column, and compressed spring is between the first block and the second block.

The utility model is used as it is further preferred that rotation drive device includes driving motor and worm screw；Lifting platform upper end It is provided with retaining-plate, lifter plate side wall and retaining-plate are connected with each other, and driving motor is arranged in mounting table upper end, the rotation of driving motor Shaft passes through retaining-plate and is connected with each other with worm screw, and worm screw is located in lifter plate, the snail that lifter plate offers convenient for worm screw rotation Bar slot, worm screw are located between two positioning rings.

The utility model is as it is further preferred that the lower end of any positioning ring is provided with the positioning of multiple annular spreads Unit, positioning unit include locating slot, locating piece and retaining spring；Locating slot is provided with the lower end of any positioning ring, locating piece It is arranged in locating slot by retaining spring, locating piece is hemispherical, and the inner wall lower end of any placing groove is offered for placing The annular groove of locating piece.

The beneficial effects of the utility model are as follows:

1, the utility model clears up the steel slag of oxygen rifle body outer wall by scraping slag unit, and scraping slag unit can be adaptive Property it is flexible, adapt to more taper oxygen rifles situation not of uniform size in the outer diameter of different parts, dreg scraper knife made to follow more taper oxygen The outer wall of rifle carries out adaptive change, remains that scraping slag is in close contact with oxygen rifle body outer wall, is effectively ensured to more tapers The case where steel slag of oxygen rifle outer wall carries out the stifled cleaning of vehicle, and dreg scraper knife position is effectively avoided to remain unchanged, and cause to oxygen rifle ontology The steel slag of outer wall clears up halfway problem.

2, by the way that a guide post was arranged between upper backup pad and lower supporting plate, lifter plate is positioned, guarantees lifting Plate keeps lifter plate to move synchronously with lifting platform in lifting process, and the relative position of oxygen therapy pipeline and oxygen rifle ontology is kept not Become, that is, realizes positioning of the slag-scraper to oxygen rifle ontology, in the actual production process, slag-scraper position opposite with oxygen rifle ontology It sets i.e. fixed, when needing to carry out scraping Slag treatment to oxygen rifle body outer wall, does not need secondary positioning and can fast implement to scrape at slag Reason；Carrying out lifting to lifting platform by hydraulic cylinder simultaneously ensure that stability of the lifting platform in lifting process.

3, scrape the working principle of slag unit: adjacent scrape is provided with gap between slag unit, positioning column is removable in positioning sleeve Dynamic, during scraping slag, the lifting of slag unit is scraped in elevation driving unit drive, and dreg scraper knife is protected always under the action of compressed spring Holding, by positioning column transmission force, makes positioning column since the outer diameter gradual change of steep-taper oxygen lance outer wall increases with the contact of oxygen rifle outer wall The power to positioning sleeve is generated, compresses compressed spring further, arc panel is mobile to the direction far from oxygen rifle outer wall, increases The outer diameter of arc panel, to adapt to steep-taper oxygen lance outer wall；Similarly, when oxygen rifle outer wall outer diameter is gradually reduced, arc panel is in compression bullet It is mobile to the direction close to oxygen rifle ontology under the action of spring, reduce arc panel it is outer into, guarantee dreg scraper knife always with oxygen rifle ontology Outer wall is in close contact, so as to by the steel slag scraped clean of oxygen rifle outer wall.

4, the driving device of rotating ring realizes that working principle is whirlpool by the tooth that worm screw and rotating ring lateral wall are arranged The transmission principle of worm and gear, lifter plate are connected with each other by retaining-plate and lifting platform, ensure that the connection of lifter plate and lifting platform Stability, the rotary shaft of driving motor is extend into lifter plate after passing through retaining-plate and worm screw is connected with each other, structurally reasonable, makes to drive The stress of motor is moved on mounting table, meanwhile, run through retaining-plate, guarantees the stability of driving motor during the work time, worm screw One end and driving motor be connected with each other, the inner wall of the other end and lifter plate is rotatablely connected, worm screw and the intermeshing position of tooth Between the positioning ring of rotating ring upper and lower ends, during realizing worm-drive, the dry of worm screw and positioning ring is avoided It relates to；The positioning ring of rotating ring upper and lower ends passes through bolt and rotating ring is connected with each other, and the side wall of through-hole offers two annulars Placing groove, placing groove and positioning ring correspond, and positioning ring is extend into locating slot, guarantees that rotating ring can occur with lifter plate It relatively rotates, while lifter plate, during lifting, the integraty of rotating ring and lifter plate, rotating ring follows lifter plate together Lifting.

5, the lower end of any positioning ring is provided with multiple positioning units, multiple positioning unit annular spreads, in placing groove Lower end be correspondingly arranged on annular sliding slot, be placed into the locating piece of positioning unit in annular groove, rotating ring is in rotation In the process, locating piece moves in annular groove, is further ensured that the stationarity of rotating ring during rotation, meanwhile, positioning Block is under the action of retaining spring, always in annular groove, guarantees the integraty of rotating ring and lifter plate.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of the utility model；

Fig. 2 is the overlooking structure diagram of lifter plate；

Fig. 3 is enlarged structure schematic diagram at A in Fig. 2；

Fig. 4 is the end structure illustration of swivel plate；

Fig. 5 is enlarged structure schematic diagram at B in Fig. 4；

Appended drawing reference: 1- oxygen rifle ontology, 110- water inlet pipe, 120- return pipe, 2- oxygen therapy pipeline, 310- upper backup pad, 320- lower supporting plate, 4- lifting platform, 410- retaining-plate, 420- guide post, 5- lifting drive, 510- hydraulic cylinder, 520- are flexible Axis, 6- lifter plate, 610- through-hole, 7- rotating ring, 710- tooth, 8- rotation drive device, 810- driving motor, 811- rotary shaft, 820- worm screw, 9- scrape slag unit, 910- dreg scraper knife, 920- arc panel, the first block of 930-, the second block of 940-, 950- positioning Set, 960- positioning column, 970- limited block, 980- compressed spring, 10- positioning ring, 11- positioning unit, 1110- locating piece, 1120- Locating slot, 1130- retaining spring.

Specific embodiment

In order to which those skilled in the art better understand the utility model, 1-5 and following embodiment with reference to the accompanying drawing The utility model is described in further detail.

Embodiment 1

More taper oxygen rifles of slag are scraped in the accurate positionin of the utility model, including oxygen rifle ontology 1, oxygen rifle ontology 1 are connected with defeated Oxygen pipeline 2, oxygen rifle ontology 1 are connected with water inlet pipe 110 and return pipe 120；Oxygen therapy pipeline 2 is arranged with lower supporting plate 320, lower support The top of plate 320 is provided with lifting platform 4, and lifting platform 4 is provided with lifting drive 5, and lifting platform 4 is connected with lifter plate 6, lifting Through-hole 610 is offered in the middle part of plate 6, rotating ring 7 is provided in through-hole 610, and rotating ring 7 is located at the lower section of oxygen rifle ontology 1, rotating ring 7 inner walls are provided with the retractable of multiple annular spreads and scrape slag unit 9, and the outer wall of rotating ring 7 offers several annular spreads Tooth 710, tooth 710 are engaged at least one rotation drive device 8, and the upper and lower ends of rotating ring 7 are provided with positioning ring 10, positioning The outer diameter of ring 10 is greater than the outer diameter of rotating ring 7, and the inner wall of through-hole 610 offers the placement of the annular convenient for placement positioning ring 10 Slot, placing groove and through-hole 610 are interconnected.

After adopting the above technical scheme, the utility model carries out clearly the steel slag of 1 outer wall of oxygen rifle ontology by scraping slag unit 9 Reason scrapes the flexible of 9 energy adaptivity of slag unit, adapts to more taper oxygen rifles situation not of uniform size in the outer diameter of different parts, Make dreg scraper knife 910 follow more taper oxygen rifles outer wall carry out adaptive change, remain scrape slag fall it is tight with 1 outer wall of oxygen rifle ontology Contiguity touching is effectively ensured and carries out the stifled cleaning of vehicle to the steel slag of more taper oxygen rifle outer walls, 910 position of dreg scraper knife is effectively avoided to keep not The case where change, and cause to clear up halfway problem to the steel slag of 1 outer wall of oxygen rifle ontology.

Embodiment 2

The present embodiment is that advanced optimizing of making on the basis of embodiment 1 is as follows: oxygen therapy pipeline 2 is also arranged be located under The upper backup pad 310 of 320 top of support plate, is provided with multiple guide posts 420 between upper backup pad 310 and lower limbs support pad, multiple Guide post 420 runs through lifting platform 4, and lifting drive 5 is hydraulic cylinder 510, and the upper of lower supporting plate 320 is arranged in hydraulic cylinder 510 End, the telescopic shaft 520 of hydraulic cylinder 510 and the lower end of lifting platform 4 are connected with each other.

After adopting the above technical scheme, by the way that a guide post 420 was arranged between upper backup pad 310 and lower supporting plate 320, Lifter plate 6 is positioned, guarantees that lifter plate 6 in lifting process, keeps lifter plate 6 to move synchronously with lifting platform 4, oxygen cathete Road 2 and the relative position of oxygen rifle ontology 1 remain unchanged, that is, positioning of the slag-scraper to oxygen rifle ontology 1 are realized, in actual production In the process, slag-scraper and 1 relative position of oxygen rifle ontology are fixed, when needing to carry out scraping Slag treatment to 1 outer wall of oxygen rifle ontology, It does not need secondary positioning and can fast implement to scrape Slag treatment；Carrying out lifting to lifting platform 4 by hydraulic cylinder 510 simultaneously ensure that liter Stability of the platform 4 in lifting process drops.

Embodiment 3

The present embodiment is that advanced optimizing of making on the basis of embodiment 1 is as follows: scrape slag unit 9 include positioning column 960, Limited block 970, the first block 930, the second block 940, positioning sleeve 950, compressed spring 980, arc panel 920 and dreg scraper knife 910； One end of positioning sleeve 950 and the inner wall of rotating ring 7 are connected with each other, and the other end of positioning sleeve 950 is hanging and is connected with the first block 930, the side interconnection of dreg scraper knife 910 and arc panel 920, the other side of arc panel 920 and positioning column 960 are connected with each other, The other end of positioning column 960 is connected with limited block 970, the one end of positioning column 960 far from limited block 970 after protruding into positioning sleeve 950 It is arranged with the second block 940, compressed spring 980 is arranged on positioning column 960, and compressed spring 980 is located at the first block 930 and second between block 940.

After adopting the above technical scheme, scraping the working principle of slag unit 9: adjacent scrape is provided with gap between slag unit 9, fixed Position column 960 moves in positioning sleeve 950, and during scraping slag, the lifting of slag unit 9, dreg scraper knife are scraped in elevation driving unit drive 910 under the action of compressed spring 980, remain with the contact of oxygen rifle outer wall, due to steep-taper oxygen lance outer wall outer diameter gradually Become and increase, by 960 transmission force of positioning column, positioning column 960 is made to generate the power to positioning sleeve 950, make compressed spring 980 into The compression of one step, arc panel 920 is mobile to the direction far from oxygen rifle outer wall, increases the outer diameter of arc panel 920, to adapt to steep-taper oxygen Rifle outer wall；Similarly, when oxygen rifle outer wall outer diameter is gradually reduced, arc panel 920 is under the action of compressed spring 980, to close to oxygen rifle The direction of ontology 1 is mobile, reduce arc panel 920 it is outer into, guarantee that dreg scraper knife 910 is in close contact with 1 outer wall of oxygen rifle ontology always, So as to by the steel slag scraped clean of oxygen rifle outer wall.

Embodiment 4

The present embodiment is that advanced optimizing of making on the basis of embodiment 1 is as follows: rotation drive device 8 includes driving electricity Machine 810 and worm screw 820；4 upper end of lifting platform is provided with retaining-plate 410, and 6 side wall of lifter plate and retaining-plate 410 are connected with each other, driving In mounting table upper end, the rotary shaft 811 of driving motor 810 passes through retaining-plate 410 and interconnects with 820 phase of worm screw the setting of motor 810 It connects, worm screw 820 is located in lifter plate 6, and lifter plate 6 offers 820 slot of worm screw rotated convenient for worm screw 820, and worm screw 820 is located at two Between a positioning ring 10.

After adopting the above technical scheme, what the driving device of rotating ring 7 was arranged by worm screw 820 and 7 lateral wall of rotating ring Tooth 710 realizes that working principle is the transmission principle of turbine and worm 820, and lifter plate 6 passes through retaining-plate 410 and 4 phase of lifting platform It connects, ensure that the connective stability of lifter plate 6 Yu lifting platform 4, the rotary shaft 811 of driving motor 810 passes through retaining-plate 410 After extend into lifter plate 6 and be connected with each other with worm screw 820, it is structurally reasonable, make the stress of driving motor 810 on mounting table, together When, run through retaining-plate 410, guarantees the stability of driving motor 810 during the work time, one end of worm screw 820 and driving motor 810 are connected with each other, and the inner wall of the other end and lifter plate 6 is rotatablely connected, and worm screw 820 and the intermeshing position of tooth 710 are located at rotation Between the positioning ring 10 of 7 upper and lower ends of change, during realizing the transmission of worm screw 820, worm screw 820 and positioning ring 10 are avoided Interference；The positioning ring 10 of 7 upper and lower ends of rotating ring is connected with each other by bolt and rotating ring 7, and the side wall of through-hole 610 opens up There are two annular placing grooves, placing groove and positioning ring 10 correspond, and positioning ring 10 is extend into locating slot 1120, guarantees rotation Change 7 can relatively rotate with lifter plate 6, while lifter plate 6 is during lifting, the one of rotating ring 7 and lifter plate 6 Property, rotating ring 7 follows 6 one lifting of lifter plate.

Embodiment 5

The present embodiment is that advanced optimizing of making on the basis of embodiment 1 is as follows: the lower end of any positioning ring 10 is all provided with It is equipped with the positioning unit 11 of multiple annular spreads, positioning unit 11 includes locating slot 1120, locating piece 1110 and retaining spring 1130；Locating slot 1120 is provided with the lower end of any positioning ring 10, and locating piece 1110 is being positioned by the setting of retaining spring 1130 In slot 1120, locating piece 1110 is hemispherical, and the inner wall lower end of any placing groove offers the ring for placement positioning block 1110 Shape sliding slot.

After adopting the above technical scheme, being provided with multiple positioning units 11, multiple positioning in the lower end of any positioning ring 10 11 annular spread of unit is correspondingly arranged on the sliding slot of annular in the lower end of placing groove, puts the locating piece 1110 of positioning unit 11 It sets in annular groove, in the course of rotation, locating piece 1110 moves rotating ring 7 in annular groove, is further ensured that rotation The stationarity of change 7 during rotation, meanwhile, locating piece 1110 is under the action of retaining spring 1130, always in annular In sliding slot, guarantee the integraty of rotating ring 7 and lifter plate 6.

The above, the only preferred embodiment of the utility model, are not intended to limit the utility model, the utility model Scope of patent protection be subject to claims, it is equivalent made by all specifications and accompanying drawing content with the utility model Structure change similarly should be included in the protection scope of the utility model.

Claims (5)

1. a kind of be accurately positioned the more taper oxygen rifles for scraping slag, including oxygen rifle ontology (1), the oxygen rifle ontology (1) are connected with oxygen therapy Pipeline (2), the oxygen rifle ontology (1) are connected with water inlet pipe (110) and return pipe (120)；

It is characterized in that, the oxygen therapy pipeline (2) is arranged with lower supporting plate (320), the top setting of the lower supporting plate (320) Having lifting platform (4), the lifting platform (4) is provided with lifting drive (5), and the lifting platform (4) is connected with lifter plate (6), It offers through-hole (610), is provided with rotating ring (7) in the through-hole (610), the rotating ring (7) in the middle part of the lifter plate (6) Positioned at the lower section of oxygen rifle ontology (1), rotating ring (7) inner wall is provided with the retractable of multiple annular spreads and scrapes slag unit (9), the outer wall of the rotating ring (7) offers the tooth (710) of several annular spreads, and the tooth (710) is engaged at least one The upper and lower ends of rotation drive device (8), the rotating ring (7) are provided with positioning ring (10), outside the positioning ring (10) Diameter is greater than the outer diameter of rotating ring (7), and the inner wall of the through-hole (610) offers the placement of the annular convenient for placement positioning ring (10) Slot, the placing groove and through-hole (610) are interconnected.

2. according to claim 1 be accurately positioned the more taper oxygen rifles for scraping slag, which is characterized in that the oxygen therapy pipeline (2) The upper backup pad (310) being also arranged with above lower supporting plate (320), the upper backup pad (310) and lower limbs support pad it Between be provided with multiple guide posts (420), multiple guide posts (420) run through lifting platform (4), and the lifting drive (5) is Hydraulic cylinder (510), the hydraulic cylinder (510) are arranged in the upper end of lower supporting plate (320), the telescopic shaft of the hydraulic cylinder (510) (520) it is connected with each other with the lower end of lifting platform (4).

3. according to claim 1 be accurately positioned the more taper oxygen rifles for scraping slag, which is characterized in that described to scrape slag unit (9) Including positioning column (960), limited block (970), the first block (930), the second block (940), positioning sleeve (950), compressed spring (980), arc panel (920) and dreg scraper knife (910)；

One end of the positioning sleeve (950) and the inner wall of rotating ring (7) are connected with each other, and the other end of the positioning sleeve (950) is outstanding Sky is simultaneously connected with the first block (930), and the side of the dreg scraper knife (910) and arc panel (920) is connected with each other, the arc panel (920) the other side and positioning column (960) is connected with each other, and the other end of the positioning column (960) connects after protruding into positioning sleeve (950) It is connected to limited block (970), the positioning column (960) is arranged with the second block (940) far from the one end of limited block (970), described Compressed spring (980) is arranged on positioning column (960), and the compressed spring (980) is located at the first block (930) and the Between two blocks (940).

4. according to claim 1 be accurately positioned the more taper oxygen rifles for scraping slag, which is characterized in that the rotation drive device It (8) include driving motor (810) and worm screw (820)；

Lifting platform (4) upper end is provided with retaining-plate (410), and lifter plate (6) side wall is mutually interconnected with retaining-plate (410) It connects, driving motor (810) setting passes through retaining-plate in mounting table upper end, the rotary shaft (811) of the driving motor (810) (410) and with worm screw (820) it is connected with each other, the worm screw (820) is located in lifter plate (6), and the lifter plate (6) offers just In worm screw (820) slot of worm screw (820) rotation, the worm screw (820) is located between two positioning rings (10).

5. according to claim 1 be accurately positioned the more taper oxygen rifles for scraping slag, which is characterized in that any positioning ring (10) lower end is provided with the positioning unit (11) of multiple annular spreads, and the positioning unit (11) includes locating slot (1120), locating piece (1110) and retaining spring (1130)；

The locating slot (1120) is provided with the lower end of any positioning ring (10), and the locating piece (1110) passes through retaining spring (1130) setting is in locating slot (1120), and the locating piece (1110) is hemispherical, and the inner wall lower end of any placing groove opens up There is the annular groove for placement positioning block (1110).