Prestressed concrete pipe pile splicing structure

Abstract

The utility model discloses a prestressed concrete pipe pile splicing structure which comprises concrete pipe pile bodies, the number of the concrete pipe pile bodies is two, the concrete pipe pile bodies are coaxially contrasted in the vertical direction, and prefabricated butt joint end plates are coaxially fixed to the opposite end faces of the concrete pipe pile bodies at the upper position and the lower position. A butt-joint sealing assembly is fixed between the opposite end faces of the butt-joint end plates at the upper position and the lower position in a limited mode through a combined fixing assembly. The concrete pipe pile has the advantages that the butt joint sealing assembly is installed at the joint position of the two sections of concrete pipe pile bodies in a combined mode through the combined fixing assembly; in this way, the two sections of concrete pipe pile bodies can be accurately limited and butted together in the mode that an insertion block and an insertion groove of the butt joint sealing assembly are in vertical sliding fit, and a locking rod penetrates through a matching hole to be horizontally and coaxially matched with a locking hole, and the accurate alignment mode of the two sections of concrete pipe pile bodies is simple and easy to achieve; and therefore, stable and reliable welding quality of the joint position of the two sections of concrete pipe pile bodies is ensured.

Description

Technical Field

[0001] The utility model relates to the field of auxiliary components for connecting concrete pipe piles, and particularly relates to a prestressed concrete pipe pile connecting structure. Background Technique

[0002] Concrete pipe piles are structural components used for building foundations. They are divided into prestressed concrete pipe piles, prestressed concrete thin-wall pipe piles, and high-strength prestressed concrete pipe piles according to the concrete strength grade and wall thickness, and play an important role in modern civil engineering construction.

[0003] Specifically, when connecting concrete pipe piles, currently, usually two sections of concrete pipe piles are butted against each other, and then the entire circumference of the joint position is welded by welding to achieve the connection of the two sections of concrete pipe piles. When the above connection operation is carried out, first, it is very difficult to accurately align the two sections of concrete pipe piles together, which will directly affect the weld quality of subsequent welding. At the same time, the waterproof treatment at the joint position between concrete pipe piles is general, and it is easy for the inside of the concrete pipe piles to be flooded due to external water seepage. Content of the Utility Model

[0004] The purpose of the utility model is to provide a prestressed concrete pipe pile connecting structure to solve the above problems. By combining and installing a butt joint sealing component at the joint position of two sections of concrete pipe pile bodies through a combined fixing component, the two sections of concrete pipe pile bodies can be accurately limited and butted together by the vertical sliding fit of the insertion block and the slot of the butt joint sealing component and the horizontal coaxial fit of the locking rod passing through the matching hole and the locking hole. The accurate alignment method of the two sections of concrete pipe pile bodies is simple and easy to implement, as described in detail below.

[0005] To achieve the above purpose, the utility model provides the following technical solutions:

[0006] A prestressed concrete pipe pile connecting structure provided by the utility model includes concrete pipe pile bodies. The number of the concrete pipe pile bodies is two and they are coaxially aligned vertically. The end faces of the concrete pipe pile bodies at the upper and lower positions facing each other are coaxially fixed with prefabricated butt joint end plates.

[0007] A butt joint sealing component is limited and fixed between the end faces of the butt joint end plates at the upper and lower positions facing each other through a combined fixing component, so as to accurately limit and butt the concrete pipe pile bodies at the upper and lower positions together through the butt joint sealing component.

[0008] Preferably, the docking seal assembly includes movable backing plates and locking rods. The number of the movable backing plates is two, and the two movable backing plates are coaxially fixed to the opposite end faces of the docking end plates at the upper and lower positions respectively through the combined fixing assembly. On both sides of the opposite end faces of the movable backing plates at the upper and lower positions, slots are vertically formed and blocks are vertically fixed respectively. The blocks and the slots correspond to each other one by one and are vertically slidably engaged. On the outer sides of the blocks at both side positions away from each other, locking holes are horizontally formed along the transverse direction. On both outer sides of the movable backing plate at the lower position, fitting holes are horizontally formed along the transverse direction, and the fitting holes and the locking holes are horizontally coaxially aligned respectively. The locking rods are coaxially inserted and fixed through each group of horizontally aligned fitting holes and locking holes along the transverse direction.

[0009] Preferably, the docking end plates and the movable backing plates are both annular plates, and the opposite end faces of the movable backing plates at the upper and lower positions are in contact with each other.

[0010] Preferably, the horizontal cross-sectional shapes of the blocks and the slots are both rectangular, the slots are all blind slots, and the vertical dimensions of the blocks are not greater than the vertical dimensions of the corresponding slots.

[0011] Preferably, the fitting holes and the locking holes are both threaded through holes, the locking rods are all screw rods, and the locking rods and the fitting holes and the locking holes are coaxially inserted and fixed through threaded engagement.

[0012] Preferably, the outer ends of the locking rods do not protrude out of the outer ends of the corresponding fitting holes, and the outer ends of the locking rods are coaxially provided with force application grooves for facilitating rotation operation.

[0013] Preferably, sealing ring grooves are coaxially formed at the inner ring positions of the opposite end faces of the movable backing plates at the upper and lower positions. A sealing ring is coaxially sleeved between the sealing ring grooves at the upper and lower positions, and the vertical dimension of the sealing ring is greater than the sum of the vertical dimensions of the sealing ring grooves at the upper and lower positions, so as to perform waterproof treatment on the inner periphery of the joint position by means of the upper and lower end faces of the sealing ring being extruded by the sealing ring grooves.

[0014] Preferably, the combined fixing component includes connecting holes and mounting holes. On the end faces of the docking end plates at the upper and lower positions facing each other, a plurality of the connecting holes evenly distributed along the circumference are pre-opened, and the connecting holes at the upper and lower positions are coaxially aligned respectively. Mounting holes are vertically opened at the front and rear positions of the movable backing plates at the upper and lower positions, and the mounting holes are coaxially aligned with one of the adjacent connecting holes respectively. Hidden grooves are coaxially opened at the outer peripheral positions of the mounting holes on the end faces of the movable backing plates at the upper and lower positions facing each other. Connecting bolts are coaxially inserted and fixed in each group of coaxially aligned mounting holes and connecting holes, and the ends of the connecting bolts are recessed and hidden in the corresponding hidden grooves.

[0015] Preferably, sealing washers are coaxially sleeved between the end faces of the movable backing plate and the docking end plate facing each other, and the connecting bolts all pass through the corresponding sealing washers.

[0016] By adopting the above prestressed concrete pipe pile splicing structure, specifically during the splicing operation of two concrete pipe pile bodies, the movable backing plates of the docking and sealing component can be coaxially fixed to the docking end plates of the corresponding concrete pipe pile bodies respectively by the connecting bolts of the combined fixing component passing through the mounting holes and the connecting holes in sequence. The fixing method of the movable backing plates is simple and easy to implement. At the same time, since the existing docking end plates at the ends of the concrete pipe pile bodies are utilized, it is more convenient to assemble the docking and sealing component at the end positions of the concrete pipe pile bodies. And because the docking and sealing component is assembled and installed at the joint position of the two concrete pipe pile bodies through the combined fixing component, in this way, the two concrete pipe pile bodies can be accurately limited and butted together by the vertical sliding fit of the insertion blocks and the slots of the docking and sealing component and the horizontal coaxial fit of the locking rods passing through the mating holes and the locking holes. The accurate alignment method of the two concrete pipe pile bodies is simple and easy to implement. After the two concrete pipe pile bodies are aligned, the entire joint position can be welded by welding, thereby ensuring the stable and reliable weld quality at the joint position of the two concrete pipe pile bodies. And specifically during the sliding fit of the insertion blocks and the slots, the inner waterproof treatment of the joint position of the two concrete pipe pile bodies can be realized by the coaxial fit of the sealing sleeves and the sealing ring grooves at the upper and lower positions and the extrusion deformation of the sealing sleeves, avoiding the internal water ingress caused by external water seepage at the joint position of the two concrete pipe pile bodies.

[0017] The beneficial effects are as follows: 1. The utility model combines and installs the butt joint sealing component at the joint position of two concrete pipe pile bodies through the combined fixing component. In this way, the two concrete pipe pile bodies can be accurately limited and butted together by the vertical sliding fit of the insertion block and the slot of the butt joint sealing component and the horizontal coaxial fit of the locking rod passing through the cooperation hole and the locking hole. The accurate alignment method of the two concrete pipe pile bodies is simple and easy to achieve, thus ensuring the stable and reliable weld quality at the joint position of the two concrete pipe pile bodies;

[0018] 2. During the sliding fit of the insertion block and the slot, the inner waterproof treatment of the joint position of the two concrete pipe pile bodies can be realized by the coaxial fit of the sealing sleeve ring with the upper and lower sealing ring grooves and the extrusion deformation of the sealing sleeve ring by the upper and lower parts, avoiding the internal water ingress caused by external water seepage at the joint position of the two concrete pipe pile bodies;

[0019] 3. By passing the connecting bolts of the combined fixing component through the mounting holes and the connecting holes in sequence, the movable backing plates of the butt joint sealing component can be coaxially fixed on the corresponding butt end plates of the concrete pipe pile bodies respectively. The fixing method of the movable backing plates is simple and easy to achieve. At the same time, due to the use of the existing butt end plates at the ends of the concrete pipe pile bodies, it is more convenient to combine the butt joint sealing component at the end positions of the concrete pipe pile bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 is the overall axonometric schematic diagram of the present utility model;

[0022] Figure 2 is the present utility model Figure 1 sectional schematic Figure 1 ;

[0023] Figure 3 is the present utility model Figure 3 partial enlarged view at A;

[0024] Figure 4 is the present utility model Figure 1 sectional schematic Figure 2 ;

[0025] Figure 5 is the present utility model Figure 4 partial enlarged view at B;

[0026] Figure 6 is a schematic cross-section of the utility model Figure 1 ; Figure 3 ;

[0027] Figure 7 is a partial enlarged view of the C part of the utility model Figure 6 ;

[0028] Figure 8 is a front external view of the utility model Figure 1 ;

[0029] Figure 9 is a left external view of the utility model Figure 1 ;

[0030] Figure 10 is a right external view of the utility model Figure 1 ;

[0031] Figure 11 is a top external view of the utility model Figure 1 ;

[0032] The description of the reference numerals is as follows:

[0033] 1. Concrete pipe pile body; 101. Docking end plate; 2. Docking seal assembly; 201. Movable backing plate; 202. Slot; 203. Insert block; 204. Locking hole; 205. Locking rod; 206. Force application groove; 207. Matching hole; 208. Sealing ring groove; 209. Sealing sleeve ring; 3. Combined fixing assembly; 301. Connecting hole; 302. Mounting hole; 303. Connecting bolt; 304. Hidden groove; 305. End; 306. Sealing washer. Detailed implementation manners

[0034] To make the objectives, technical solutions and advantages of the utility model clearer, the technical solutions of the utility model will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. All other implementation manners obtained by those of ordinary skill in the art based on the embodiments of the utility model without any creative effort fall within the scope of protection of the utility model.

[0035] See Figures 1 - 11As shown in the figure, the utility model provides a prestressed concrete pipe pile splicing structure, which includes a concrete pipe pile body 1. The number of the concrete pipe pile bodies 1 is two and they are coaxially aligned vertically. The end faces of the concrete pipe pile bodies 1 at the upper and lower positions that face each other are coaxially fixed with prefabricated butt end plates 101 respectively, so as to fix and set the butt joint sealing assembly 2 by means of the existing butt end plates 101 of the concrete pipe pile body 1. Then, due to the use of the existing butt end plates 101 at the ends of the concrete pipe pile body 1, it is convenient to assemble the butt joint sealing assembly 2 at the end positions of the concrete pipe pile body 1.

[0036] See Figures 1 - 7 As shown in the figure, a butt joint sealing assembly 2 is limited and fixed between the end faces of the butt end plates 101 at the upper and lower positions through a combined fixing assembly 3, so as to accurately limit and butt the concrete pipe pile bodies 1 at the upper and lower positions together through the butt joint sealing assembly 2. Specifically, the butt joint sealing assembly 2 includes movable backing plates 201 and locking rods 205. The number of the movable backing plates 201 is two, and they are coaxially fixed on the end faces of the butt end plates 101 at the upper and lower positions that face each other respectively through the combined fixing assembly 3. Slots 202 are vertically opened on both sides of the end faces of the movable backing plates 201 at the upper and lower positions that face each other, and insertion blocks 203 are vertically fixed. The insertion blocks 203 and the slots 202 correspond to each other one by one and are vertically slidably matched. Locking holes 204 are horizontally opened on the outer sides of the insertion blocks 203 at both positions away from each other along the transverse direction. Matching holes 207 are horizontally opened on both outer sides of the movable backing plate 201 at the lower position along the transverse direction, and the matching holes 207 and the locking holes 204 are coaxially aligned horizontally respectively. Each group of horizontally aligned matching holes 207 and locking holes 204 are coaxially penetrated and fixed with locking rods 205 along the transverse direction. The purpose of such a setting is that the two concrete pipe pile bodies 1 can be accurately limited and butted together by the vertical sliding fit of the insertion blocks 203 and the slots 202 of the butt joint sealing assembly 2 and the horizontal coaxial fit of the locking rods 205 passing through the matching holes 207 and the locking holes 204, and the accurate alignment method of the two concrete pipe pile bodies 1 is simple and easy to implement.

[0037] Meanwhile, the combined fixing component 3 includes a connection hole 301 and a mounting hole 302. A plurality of connection holes 301 that are evenly distributed along the circumference are pre-opened on the opposite end faces of the docking end plates 101 at the upper and lower positions, and the connection holes 301 at the upper and lower positions are coaxially aligned respectively. Mounting holes 302 are vertically opened at the front and rear positions of the movable backing plates 201 at the upper and lower positions, and the mounting holes 302 are coaxially aligned with one of the adjacent connection holes 301 respectively. Hidden grooves 304 are coaxially opened at the outer peripheral positions of the mounting holes 302 on the opposite end faces of the movable backing plates 201 at the upper and lower positions. A connecting bolt 303 is coaxially inserted and fixed in each set of coaxially aligned mounting hole 302 and connection hole 301, and the end heads 305 of the connecting bolts 303 are all recessed and hidden in the corresponding hidden grooves 304. The advantage of such a setting is that the movable backing plates 201 of the docking and sealing component 2 can be coaxially fixed to the docking end plates 101 of the corresponding concrete pipe piles 1 respectively by the way that the connecting bolts 303 of the combined fixing component 3 pass through the mounting holes 302 and the connection holes 301 in sequence, and the fixing method of the movable backing plates 201 is simple and easy to implement.

[0038] See Figures 1 - 7 As shown, the docking and sealing component 2 and the combined fixing component 3 are respectively optimized as follows. Specifically for the docking and sealing component 2, both the docking end plate 101 and the movable backing plate 201 are circular ring plates, and the opposite end faces of the movable backing plates 201 at the upper and lower positions are in fitting contact. With such a setting, it is convenient for both the docking end plate 101 and the movable backing plate 201 to have shapes and styles that meet the actual use. At the same time, the stable alignment of the two concrete pipe piles 1 can also be ensured by the way that the opposite end faces of the movable backing plates 201 are in fitting contact. Optionally, the horizontal cross-sectional shapes of both the insertion blocks 203 and the slots 202 are rectangles, the slots 202 are all blind slots, and the vertical dimensions of the insertion blocks 203 are not greater than the vertical dimensions of the corresponding slots 202. With such a setting, firstly, it is convenient for the insertion blocks 203 and the slots 202 to have a good positioning and guiding design during vertical sliding cooperation, and secondly, it is convenient to prevent the insertion blocks 203 from being too long and causing the opposite end faces of the movable backing plates 201 to fail to be in fitting contact.

[0039] Optionally, both the mating hole 207 and the locking hole 204 are threaded through holes, and the locking rods 205 are all screw rods. The locking rods 205 are coaxially inserted and fixed with the mating hole 207 and the locking hole 204 by means of thread fitting, so that the locking rods 205 can be quickly combined and connected with the mating hole 207 and the locking hole 204 by screwing the locking rods 205. Preferably, the outer ends of the locking rods 205 do not protrude from the outer ends of the corresponding mating holes 207, and the outer ends of the locking rods 205 are coaxially provided with force application grooves 206 for facilitating rotation operation. With such a setting, firstly, it is convenient to hide the outer ends of the locking rods 205 inside the mating holes 207 by means of plugging. Optionally, the force application grooves 206 are internal hexagonal grooves, so as to facilitate screwing the locking rods 205 with a hexagonal wrench tool to be coaxially connected with the mating hole 207 and the locking hole 204. Further optionally, the end faces of the upper and lower movable backing plates 201 facing each other are coaxially provided with sealing ring grooves 208 at the inner ring position. A sealing ring 209 is coaxially sleeved between the upper and lower sealing ring grooves 208, and the vertical dimension of the sealing ring 209 is greater than the sum of the vertical dimensions of the upper and lower sealing ring grooves 208. The inner circumference of the joint position is waterproofed by the upper and lower end faces of the sealing ring 209 being squeezed by the sealing ring grooves 208. With such a setting, during the sliding fit process of the insert block 203 and the slot 202, the inner circumference of the joint position of the two concrete pipe pile bodies 1 can be waterproofed by the sealing ring 209 being coaxially fitted with the upper and lower sealing ring grooves 208 and being squeezed and deformed up and down, avoiding internal water ingress due to external water seepage at the joint position of the two concrete pipe pile bodies 1.

[0040] Specifically for the combined fixing assembly 3, sealing washers 306 are coaxially sleeved between the end faces of the movable backing plate 201 and the docking end plate 101 facing each other, and the connecting bolts 303 all pass through the corresponding sealing washers 306. The reason for such a setting is that by tightening the connecting bolts 303, the sealing washers 306 can be squeezed and deformed, and then the joint surfaces of the movable backing plate 201 and the docking end plate 101 can be well sealed by the squeezing and deformation of the sealing washers 306, thus achieving a stable waterproofing effect.

[0041] With the above structure, specifically during the process of splicing two concrete pipe pile bodies 1, the movable backing plates 201 of the butt joint sealing assembly 2 can be coaxially fixed to the butt end plates 101 of the corresponding concrete pipe pile bodies 1 respectively by passing the connecting bolts 303 of the combined fixing assembly 3 through the mounting holes 302 and the connecting holes 301 in sequence. The fixing method of the movable backing plates 201 is simple and easy to implement. At the same time, due to the use of the existing butt end plates 101 at the ends of the concrete pipe pile bodies 1, it is more convenient to assemble the butt joint sealing assembly 2 at the end positions of the concrete pipe pile bodies 1. And because the butt joint sealing assembly 2 is assembled at the joint position of the two concrete pipe pile bodies 1 through the combined fixing assembly 3, in this way, the two concrete pipe pile bodies 1 can be accurately positioned and butted together by the vertical sliding fit of the insertion block 203 and the slot 202 of the butt joint sealing assembly 2 and the horizontal coaxial fit of the locking rod 205 passing through the mating hole 207 and the locking hole 204. The accurate alignment method of the two concrete pipe pile bodies 1 is simple and easy to implement. After the two concrete pipe pile bodies 1 are aligned, the entire circumference of the joint position can be welded by welding, thus ensuring the stable and reliable weld quality at the joint position of the two concrete pipe pile bodies 1. And specifically during the sliding fit of the insertion block 203 and the slot 202, the inner waterproof treatment of the joint position of the two concrete pipe pile bodies 1 can be realized by the coaxial fit of the sealing ring 209 with the upper and lower sealing ring grooves 208 respectively and being squeezed and deformed up and down, avoiding the internal water ingress caused by external water seepage at the joint position of the two concrete pipe pile bodies 1.

[0042] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claimed rights.

Claims

1. A prestressed concrete pipe pile connection structure, comprising a concrete pipe pile body (1), characterized in that: The concrete pipe pile body (1) is in two sections and is coaxially opposed in the vertical direction, and the end surfaces of the concrete pipe pile bodies (1) at the upper and lower positions facing each other are coaxially fixed with prefabricated butt end plates (101); A butt sealing component (2) is fixed between the end surfaces of the butt end plates (101) at the upper and lower positions facing each other via a combined fixing component (3), so that the concrete pipe pile bodies (1) at the upper and lower positions can be accurately butt-jointed together via the butt sealing component (2).

2. The prestressed concrete pipe pile connection structure according to claim 1, characterized in that: The butt seal assembly (2) comprises a movable pad (201) and a locking rod (205); the movable pads (201) are two in number and are coaxially fixed to the end surfaces of the butt end plates (101) at upper and lower positions respectively through the combined fixing assembly (3); both sides of the end surfaces of the movable pads (201) at upper and lower positions respectively have slots (202) vertically formed and plug blocks (203) vertically fixed thereto; the plug blocks (203) correspond one to one with the slots (202). The insert blocks (203) at both sides are slidably matched vertically, and the outer side surfaces away from each other are provided with locking holes (204) horizontally, and the outer sides of the movable pad (201) at the lower position are provided with matching holes (207) horizontally, and the matching holes (207) and the locking holes (204) are respectively coaxially matched horizontally, and each group of the matching holes (207) and the locking holes (204) are coaxially inserted and fixed with the locking rod (205) along the horizontal direction.

3. The prestressed concrete pipe pile connection structure according to claim 2, characterized in that: The butt-jointed end plate (101) and the movable pad (201) are both annular plates, and the end surfaces of the movable pads (201) at upper and lower positions that face each other are in close contact with each other.

4. The prestressed concrete pipe pile connection structure according to claim 3, characterized in that: The horizontal cross-sectional shapes of the insert block (203) and the slot (202) are both rectangular, the slots (202) are all blind slots, and the vertical dimensions of the insert block (203) are not greater than the vertical dimensions of the corresponding slots (202).

5. The prestressed concrete pipe pile connection structure according to claim 4, characterized in that: The matching hole (207) and the locking hole (204) are both threaded through holes, the locking rod (205) is a screw rod, and the locking rod (205) is coaxially interlaced and fixed with the matching hole (207) and the locking hole (204) by means of threaded matching.

6. The prestressed concrete pipe pile connection structure according to claim 5, characterized in that: The outer ends of the locking rods (205) do not expose the corresponding outer ends of the matching holes (207), and the outer ends of the locking rods (205) are coaxially provided with force application grooves (206) for facilitating the rotation operation.

7. A prestressed concrete pipe pile connection structure according to any one of claims 2 to 6, characterized in that: The end faces of the movable pads (201) at the upper and lower positions facing each other are coaxially provided with sealing ring grooves (208) at the inner circle position, and a sealing ring (209) is coaxially sleeved between the sealing ring grooves (208) at the upper and lower positions, and the vertical dimension of the sealing ring (209) is larger than the sum of the vertical dimensions of the sealing ring grooves (208) at the upper and lower positions, so as to waterproof the inner periphery of the joint position by squeezing the upper and lower end faces of the sealing ring (209) by the sealing ring groove (208).

8. The prestressed concrete pipe pile connection structure according to claim 7, characterized in that: The combined fixing component (3) comprises a connecting hole (301) and a mounting hole (302); the end surfaces of the upper and lower butt-jointed end plates (101) facing each other are pre-opened with a plurality of connecting holes (301) evenly distributed along the circumference, and the connecting holes (301) at the upper and lower positions are respectively coaxially opposed; the front and rear positions of the upper and lower movable pads (201) are vertically opened with the mounting holes (302), and the mounting holes (302) are respectively coaxially opposed to one of the adjacent connecting holes (301); the end surfaces of the upper and lower movable pads (201) facing each other are coaxially opened with hidden grooves (304) at the peripheral positions of the mounting holes (302); each group of the coaxially opposed mounting holes (302) and the connecting holes (301) are coaxially interspersed and fixed with connecting bolts (303), and the ends (305) of the connecting bolts (303) are sunk and hidden in the corresponding hidden grooves (304).

9. The prestressed concrete pipe pile connection structure according to claim 8, characterized in that: Sealing gaskets (306) are coaxially sleeved between the end surfaces of the movable pad (201) and the butt end plate (101) facing each other, and the connecting bolts (303) pass through the corresponding sealing gaskets (306).

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