Preparation process of anti-theft fire hydrant

Abstract

The present application relates to the technical field of fire-fighting equipment, and particularly relates to a preparation process of a theftproof fire hydrant, comprising the following steps: a, preparing a plug body; b, installing a valve core and a valve rod for fluid control into the plug body, and screwing an interface on a water outlet pipeline; c, preparing an end cover: c1, stamping, cutting and bending a metal plate to obtain an end cover blank, the end cover blank is formed with an upper connecting part and a lower connecting part matched with the upper connecting lug and the lower connecting lug, and is formed with an upper side of the end cover and a lower side of the end cover matched with the high stepped surface and the low stepped surface respectively, the height of the lower side of the end cover is less than the height of the low stepped surface; c2, performing plastic dipping treatment on the obtained end cover blank to obtain the end cover. The present application solves the problems of high production cost and large installation difficulty caused by the complicated theftproof structure of the fire hydrant interface.

Description

Technical Field

[0001] This invention relates to the field of fire protection equipment technology, and specifically to a manufacturing process for an anti-theft fire hydrant. Background Technology

[0002] A fire hydrant, also known as a fire hose, is a fixed fire-fighting facility. Its main function is to control combustibles, isolate oxidizers, and eliminate ignition sources. There are indoor and outdoor fire hydrants. They primarily allow fire trucks to draw water from municipal water supply networks or outdoor fire water supply networks for firefighting. They can also be directly connected to hoses and nozzles for firefighting. Currently, copper connectors on fire hydrants are frequently stolen. To address this, corresponding products have emerged on the market, such as the anti-theft device for fire hydrant connectors shown in Chinese patent CN202090395 U. This device includes a valve body, a connector, and a side cover. The connector has a first left-hand rotating thread and a second right-hand rotating thread with opposite helical directions. The valve body has a third thread that matches the first left-hand rotating thread, and the second right-hand rotating thread is fitted with an anti-theft lock cap with a fourth thread that matches it.

[0003] The technical solution incorporates a corresponding anti-theft structure to prevent interface theft. However, this structure is complex, difficult to install and manufacture, and costly. Summary of the Invention

[0004] Therefore, the present invention provides a manufacturing process for an anti-theft fire hydrant, which solves the problems of high production costs and difficult installation caused by the complicated anti-theft structure of the fire hydrant interface.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] A manufacturing process for an anti-theft fire hydrant includes the following steps:

[0007] a. Preparation of the hydrant body: This includes casting the hydrant body, heat-treating and cooling it to form a hydrant body with one or more water outlet pipes, grinding the inner and outer surfaces of the obtained hydrant body, and performing anti-corrosion and waterproof treatment on the inner and outer surfaces. The inner wall of the water outlet pipe is tapped to form an internal thread for the installation interface, thus obtaining the hydrant body. An upper connecting lug and a lower connecting lug for installation are formed on the outer peripheral surface of the water outlet pipe on the hydrant body. The end surface of the water outlet pipe has a stepped relief surface, forming a high-step surface and a low-step surface, and the stepped surface is ground. The upper connecting lug is located at the upper end of the high-step surface, and the lower connecting lug is located at the lower end of the low-step surface.

[0008] b. Install the valve core and valve stem for fluid control into the plug body, and screw the interface onto the outlet pipe;

[0009] c. Preparation of end caps:

[0010] c1. Take a metal plate and stamp, cut and bend it to obtain an end cap blank. An upper connecting part and a lower connecting part are formed on the end cap blank to cooperate with the upper connecting ear and the lower connecting ear. An upper side surface and a lower side surface of the end cap are formed to adapt to the higher step surface and the lower step surface respectively. The height of the lower side surface of the end cap is less than the height of the lower step surface.

[0011] c2. The obtained end cap preform is subjected to dip-coating treatment to obtain the end cap;

[0012] d. Assemble the end cap, align the end cap with the stepped surface of the water outlet pipe, and then gradually move the lower connecting part downward from the lower stepped surface so that the upper connecting part is hung on the upper connecting ear, and the lower connecting part is inserted into the lower connecting ear, so that the upper side of the end cap is in contact with the higher stepped surface and the lower side of the end cap is in contact with the lower stepped surface. A hollow groove is formed between the lower side of the end cap and the lower stepped surface, and a transverse fixing pin is inserted from one side of the hollow groove. The transverse fixing pin is a frustum-shaped structure with a gradually changing diameter.

[0013] Preferably, step a above further includes two transverse connecting ears that are symmetrically distributed between the upper connecting ear and the lower connecting ear after casting; step c1 above further includes a transverse connecting portion that is adapted to the transverse connecting ears formed on the end cap blank.

[0014] Preferably, an axial fixing hole is provided at the corresponding position of the transverse connecting ear and the transverse connecting part, and an axial fixing pin is inserted into the axial fixing hole.

[0015] Preferably, the thickness of the lateral connecting ear gradually decreases from its free end inward.

[0016] Preferably, in step a above, a locking groove is formed on the lower connecting ear; in step c1 above, a protruding locking block adapted to the locking groove is provided on the lower connecting part.

[0017] Preferably, the lower end of the end cap is provided with an arc-shaped filling piece for filling the gap between it and the water outlet pipe.

[0018] Preferably, in step d above, after the transverse fixing pin is installed, filler is bonded to both ends of it.

[0019] By adopting the aforementioned technical solution, the beneficial effects of the present invention are:

[0020] This technical solution specifically designs an end cap structure for the protection and anti-theft of copper interfaces of fire hydrants. During the production process, the end cap adopts a prefabricated sandwich metal blank, and then wraps a tough plastic outer layer through dip coating to meet the requirements of structural installation, fastening and protection. The material and structure of the end cap are not easily damaged. Compared with the traditional metal end cap structure, it is lighter in weight and easier to form. Compared with the metal casting process, it has higher production precision, which facilitates assembly and transportation and reduces the number of post-processing steps.

[0021] During installation, the upper connecting part snaps into the upper connecting ear, and the lower connecting part inserts into the lower connecting ear. Combined with the transverse fixing pin at the middle recessed groove, a stable tenon joint structure is formed. The end cap conceals the transverse fixing pin inside. The entire installation structure does not have common disassembly and assembly components such as screws on the outer surface, providing strong concealment. The transverse fixing pin is inserted with an interference fit, which not only ensures a tight connection between the end cap and the water outlet pipe, but also requires the transverse fixing pin to be knocked out by external force from the opposite direction of insertion when disassembly is needed. This makes disassembly and assembly difficult and further enhances theft prevention. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the external structure of a fire hydrant according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram (direction A) of the external structure of the end face and the water outlet pipe in one embodiment of the present invention;

[0024] Figure 3 This is a cross-sectional view (BB direction) of the end face and the water outlet pipe in one embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the external structure of the end face and the water outlet pipe according to a second embodiment of the present invention.

[0026] Figure 5 for Figure 4 Schematic diagram of the cross-sectional structure along the CC direction;

[0027] Figure 6 This is a cross-sectional view of the third embodiment of the present invention along the CC direction;

[0028] Figure 7 This is a schematic diagram of the end face structure of the end cap and the water outlet pipe according to an embodiment of the present invention;

[0029] Figure 8 This is a schematic diagram of the surface structure of the end cap.

[0030] Reference numerals: 1. Outlet pipe; 11. Recessed surface; 11a. Higher stepped surface; 11b. Lower stepped surface; 12. Upper connecting lug; 121. Upper connecting groove; 13. Lower connecting lug; 131. Lower connecting block; 14. Lateral connecting lug; 2. Interface; 3. End cap; 3a. Blank; 3b. Outer shell; 3c. Upper side; 3d. Lower side; 31. Upper connecting part; 32. Lower connecting part; 33. Locking block; 34. Arc-shaped filling piece; 35. Filler; 36. Lateral connecting part; 37. Axial fixing pin; 4. Lateral fixing pin. Detailed Implementation

[0031] The following will describe in detail the implementation of the present invention with reference to specific embodiments, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0032] refer to Figures 1 to 6 The structure of the anti-theft fire hydrant shown in this technical solution is as follows:

[0033] like Figure 1 , Figure 2 and Figure 3 An anti-theft fire hydrant includes a fire hydrant body with three water outlet pipes 1. Each water outlet pipe 1 is screwed with an interface 2. An end cap 3 is installed at the end of each water outlet pipe 1, covering the interface 2. The water outlet direction of the water outlet pipe 1 is defined as outward and the opposite direction as inward. The end surface of the water outlet pipe 1 has a relief surface 11 extending inward. The outer surface of the water outlet pipe 1 has symmetrically distributed upper connecting ears 12 and lower connecting ears 13. Both the upper connecting ears 12 and the lower connecting ears 13 protrude radially outward from the water outlet pipe 1. The upper connecting ear 12 has an upper connecting groove 121 located inward, and the lower connecting ear 13 has a lower connecting block 131 protruding inward.

[0034] The end cap 3 is provided with an upper connecting part 31 and a lower connecting part 32 that are adapted to the upper connecting groove 121 and the lower connecting block 131, respectively. The cross-sections of the upper connecting part 31 and the lower connecting block 131 are both "L" shaped.

[0035] When the end cap 3 is installed at the end of the water outlet pipe 1, the lower connecting part 32 extends along the relief surface 11 and inserts into the lower connecting block 131. The upper connecting part 31 is embedded in the upper connecting groove 121 of the upper connecting ear 12. A hollow groove is formed between the relief surface 11 and the lower connecting part 32. A transverse fixing pin 4 for fixing the end cap 3 is inserted into the hollow groove. The transverse fixing pin 4 and the hollow groove are interference fit.

[0036] The upper connecting part 31 and the upper connecting groove 121, and the lower connecting part 32 and the lower connecting groove are respectively combined to form a rectangle protruding outward from the periphery of the water outlet pipe 1; this structure has an aesthetically pleasing appearance and does not have the various screws and other connecting parts of traditional anti-theft structures that are exposed.

[0037] In this embodiment, the lower end of the end cap 3 is provided with an arc-shaped filling piece 34 for filling the gap between it and the water outlet pipe 1. The arc-shaped filling piece 34 is made of foamed flexible material to fill the gap between the end cap 3 and the water outlet pipe 1, so as to prevent external debris, insects and other objects from entering and further protect the installation structure.

[0038] Meanwhile, filler 35 is bonded to both ends of the transverse fixing pin 4. The filler 35 is bonded to both ends of the transverse fixing pin 4 to make its ends flat, and then completely hidden by spraying paint. People who are not familiar with this structure cannot easily remove the end cap 3, further improving the concealment of the installation structure.

[0039] The end cap 3 is also cast and then polished to meet the installation requirements.

[0040] In addition, based on the above, we can also refer to Figure 4 , Figure 5 In contrast, the outer surface of the water outlet pipe 1 is provided with two symmetrically distributed transverse connecting ears 14, and the end cap 3 is provided with a transverse connecting part 36 adapted to the transverse connecting ears 14. The transverse connecting ears 14 and the transverse connecting parts 36 are inserted into each other. The provision of transverse connecting ears 14 adds two fixing points on the basis of the above, which can further improve the structural stability and provide further protection for the part between the upper connecting ear 12 and the lower connecting ear 13. At this time, there are four arc-shaped filling pieces 34, which fill the gaps respectively.

[0041] Structurally, axial fixing holes are provided at the corresponding positions where the transverse connecting ear 14 and the transverse connecting part 36 are inserted, and axial fixing pins 37 are inserted into the axial fixing holes. In this way, after the transverse connecting ear 14 and the transverse connecting part 36 are installed, the two components are further connected by the axial fixing pins 37, which increases the restriction in the axial direction and further improves the structural stability. Moreover, during installation, the axial fixing pins 37 are installed from the side of the water outlet pipe 1 outwards, and are not exposed in appearance, ensuring the concealment of the structure.

[0042] It can also be used as a reference. Figure 6 ,and Figure 4 , Figure 5Compared to the previous technical solution, this embodiment uses a different transverse connecting lug 14, where the thickness of the transverse connecting lug 14 gradually decreases from its free end inwards. When the transverse connecting part 36 is inserted into the transverse connecting lug 14, a dovetail joint structure is formed to prevent the end cap 3 from detaching outwards. Furthermore, in this embodiment, the end cap 3 is made of a tough plastic material. It can be PP or PA plastic with added glass fiber, etc. This material is easier to process, and after installation, the end cap 3 forms a smooth connection structure with the surface of the water outlet pipe 1, resulting in an aesthetically pleasing appearance. The use of a tough plastic material not only facilitates molding but also assembly and transportation. It also better accommodates the disadvantages of metal fire hydrant bodies, which are difficult to precision machine, thus possessing good practicality.

[0043] This technical solution is derived from the fact that the end cap 3 is made of tough plastic material.

[0044] Specifically, it is a manufacturing process for an anti-theft fire hydrant, comprising the following steps:

[0045] a. Preparation of the hydrant body: This includes casting the hydrant body, heat-treating and cooling it to form a hydrant body with one or more water outlet pipes 1, grinding the inner and outer surfaces of the obtained hydrant body, and performing anti-corrosion and waterproof treatment on the inner and outer surfaces. The inner wall of the water outlet pipe 1 is tapped to form an internal thread for installing the interface 2, thereby obtaining the hydrant body. An upper connecting lug 12 and a lower connecting lug 13 for installation are formed on the outer peripheral surface of the water outlet pipe 1 on the hydrant body. The end surface of the water outlet pipe 1 is a stepped relief surface 11, forming a high stepped surface 11a and a low stepped surface 11b, and the stepped surface is ground. The upper connecting lug 12 is located at the upper end of the high stepped surface 11a, and the lower connecting lug 13 is located at the lower end of the low stepped surface 11b.

[0046] b. Install the valve core and valve stem for fluid control into the plug body, and screw the interface 2 onto the water outlet pipe 1;

[0047] c. Preparation of end cap 3:

[0048] The structure of the end cap 3 is as follows: Figure 7 , Figure 8 As shown, it has an end cap preform 3a embedded inside and a dip-molded outer shell 3b covering the end cap preform 3a; the specific molding process is as follows:

[0049] c1. Take a metal plate and stamp, cut and bend it to obtain an end cap 3 blank 3a. An upper connecting part 31 and a lower connecting part 32 are formed on the end cap 3 blank 3a to cooperate with the upper connecting ear 12 and the lower connecting ear 13. An upper side surface 3c and a lower side surface 3d of the end cap 3 are formed to be adapted to the higher step surface 11a and the lower step surface 11b respectively. The height of the lower side surface 3d of the end cap 3 is less than the height of the lower step surface 11b.

[0050] c2. The obtained end cap 3 preform 3a is subjected to dip-coating treatment to obtain end cap 3;

[0051] d. Assemble the end cap 3, aligning it with the stepped surface of the outlet pipe 1. Then, the lower connecting part 32 gradually moves downward from the lower stepped surface 11b, allowing the upper connecting part 31 to hang on the upper connecting ear 12. The lower connecting part 32 is inserted into the lower connecting ear 13, so that the upper side 3c of the end cap 3 fits against the higher stepped surface 11a, and the lower side 3d of the end cap 3 fits against the lower stepped surface 11b. A hollow groove is formed between the lower side 3d of the end cap 3 and the lower stepped surface 11b. A transverse fixing pin 4 is inserted from one side of the hollow groove. The transverse fixing pin 4 is a frustum-shaped structure with a gradually changing diameter. After the above installation, in step d, after the transverse fixing pin 4 is inserted, filler 35 is adhered to both ends of it.

[0052] In step a above, two transverse connecting ears 14 are symmetrically distributed between the upper connecting ear 12 and the lower connecting ear 13 after casting; in step c1 above, a transverse connecting portion 36 adapted to the transverse connecting ears 14 is formed on the end cap 3 blank 3a.

[0053] Specifically, an axial fixing hole is provided at the corresponding position of the insertion point of the transverse connecting ear 14 and the transverse connecting part 36, and an axial fixing pin 37 is inserted into the axial fixing hole.

[0054] Structurally, in step a above, a locking groove is provided on the lower connecting ear 13; in step c1 above, a protruding locking block 33 adapted to the locking groove is provided on the lower connecting part 32.

[0055] The lower end of the end cap 3 is provided with an arc-shaped filling piece 34 for filling the gap between it and the water outlet pipe 1.

[0056] This technical solution specifically designs an end cap 3 structure for the protection and anti-theft of the copper interface 2 of fire hydrants. During the production process, the end cap 3 adopts a prefabricated sandwich metal blank 3a, and then wraps a tough plastic outer layer through dip coating to meet the requirements of structural installation fastening and protection. The material and structure of the end cap 3 are not easily damaged. Compared with the traditional metal end cap 3 structure, it is lighter in weight and easier to form. Compared with the metal casting process, it has higher production precision, which facilitates assembly and transportation and reduces the number of post-processing steps.

[0057] During installation, the upper connecting part 31 snaps into the upper connecting ear 12, and the lower connecting part 32 inserts into the lower connecting ear 13. Together with the transverse fixing pin 4 at the middle relief groove, a stable tenon joint structure is formed. The end cover 3 conceals the transverse fixing pin 4 inside. The entire installation structure does not have common disassembly and assembly components such as screws on the outer surface, which has strong concealment. The transverse fixing pin 4 is inserted with an interference fit, which not only makes the connection structure between the end cover 3 and the water outlet pipe 1 secure, but also requires the transverse fixing pin 4 to be knocked out by external force from the opposite direction of insertion when disassembly is required. It cannot be easily disassembled, thereby further improving the anti-theft performance.

[0058] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A manufacturing process for an anti-theft fire hydrant, characterized in that, Includes the following steps: a. Preparation of the hydrant body: including casting the hydrant body, heat treatment and cooling to form a hydrant body with one or more water outlet pipes (1), and grinding the inner and outer surfaces of the obtained hydrant body, and performing anti-corrosion and waterproof treatment on the inner and outer surfaces, tapping the inner wall of the water outlet pipe (1) to form an internal thread for installing the interface (2) to obtain the hydrant body, forming an upper connecting ear (12) and a lower connecting ear (13) for installation on the outer surface of the water outlet pipe (1) on the hydrant body, and the end surface of the water outlet pipe (1) is a stepped relief surface (11) to form a high stepped surface (11a) and a low stepped surface (11b), and grinding the stepped surface, with the upper connecting ear (12) located at the upper end of the high stepped surface (11a) and the lower connecting ear (13) located at the lower end of the low stepped surface (11b); b. Install the valve core and valve stem for fluid control into the plug body, and screw the interface (2) onto the water outlet pipe (1); c. Preparation of end caps (3): c1. Take a metal plate and stamp, cut and bend it to obtain the end cap (3) blank (3a). The end cap (3) blank (3a) forms an upper connecting part (31) and a lower connecting part (32) that are fitted to the upper connecting ear (12) and the lower connecting ear (13). The end cap (3) upper side surface (3c) and the end cap (3) lower side surface (3d) are formed to fit the higher step surface (11a) and the lower step surface (11b) respectively. The height of the end cap (3) lower side surface (3d) is less than the height of the lower step surface (11b). c2. The obtained end cap (3) preform (3a) is subjected to dip plastic treatment to obtain end cap (3); d. Assemble the end cap (3), align the end cap (3) with the stepped surface of the water outlet pipe (1), and then move the lower connecting part (32) downward from the lower stepped surface (11b) and hang the upper connecting part (31) on the upper connecting ear (12). Insert the lower connecting part (32) into the lower connecting ear (13) so that the upper side (3c) of the end cap (3) fits with the high stepped surface (11a) and the lower side (3d) of the end cap (3) fits with the low stepped surface (11b). A hollow groove is formed between the lower side (3d) of the end cap (3) and the low stepped surface (11b), and a transverse fixing pin (4) is inserted from one side of the hollow groove. The transverse fixing pin (4) is a cone-shaped structure with a gradually changing diameter. The transverse fixing pin (4) and the hollow groove are interference fit. The lower end of the end cap (3) is provided with an arc-shaped filling piece (34) for filling the gap between it and the water outlet pipe (1). After the transverse fixing pin (4) is installed, filler (35) is glued to both ends of it.

2. The manufacturing process of an anti-theft fire hydrant according to claim 1, characterized in that: In step a above, two transverse connecting ears (14) are symmetrically distributed between the upper connecting ear (12) and the lower connecting ear (13) after casting; in step c1 above, a transverse connecting part (36) adapted to the transverse connecting ear (14) is formed on the end cap (3) blank (3a).

3. The manufacturing process of an anti-theft fire hydrant according to claim 2, characterized in that: An axial fixing hole is provided at the corresponding position of the insertion point of the transverse connecting ear (14) and the transverse connecting part (36), and an axial fixing pin (37) is inserted into the axial fixing hole.

4. The manufacturing process of an anti-theft fire hydrant according to claim 2, characterized in that: The thickness of the transverse connecting ear (14) gradually decreases from its free end inward.

5. The manufacturing process of an anti-theft fire hydrant according to claim 1, characterized in that: In step a above, a locking groove is provided on the lower connecting ear (13); in step c1 above, a protruding locking block (33) adapted to the locking groove is provided on the lower connecting part (32).

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