Sliding die for prestressed concrete core rod production
The continuous production of prestressed concrete mandrels is achieved through a sliding mold with U-shaped channel steel and a guiding mechanism, which solves the problems of low production efficiency and easy product damage in traditional production, and improves production efficiency and product quality.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JIANGSU OCEAN UNIV
- Filing Date
- 2025-05-27
- Publication Date
- 2026-04-24
AI Technical Summary
Traditional prestressed concrete mandrel production suffers from problems such as low production efficiency, difficulty in demolding, easy product damage, and complex construction.
A sliding mold using U-shaped channel steel and a head guide mechanism enables continuous production of prestressed concrete mandrels. The sliding of the channel steel and grouting are carried out simultaneously, and the coaxial arrangement of the guide steel plate and the prestressing tendons ensures production continuity and product quality.
It improved production efficiency, reduced manual intervention, ensured the flatness and quality of the products, avoided mold displacement and concrete spillage, and reduced repair costs.
Smart Images
Figure CN224158584U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of prestressed concrete component production technology, and specifically discloses a sliding mold for producing prestressed concrete mandrels. Background Technology
[0002] Prestressed concrete mandrels are widely used in bridge sleepers, precast building components, and coastal corrosion-resistant projects due to their excellent crack resistance and load-bearing capacity.
[0003] Traditional production processes mainly employ the following two technical solutions:
[0004] (1) Fixed mold casting: The prestressing tendons are pre-arranged in the fixed mold, and after the concrete is poured, it is left to cure. After the strength reaches the standard, the mold is manually removed. After each molding, the mold needs to be removed for cleaning, resulting in long production interruption time, difficulty in demolding, low production efficiency, and easy damage to the surface of the mandrel due to hard demolding, which increases repair costs.
[0005] (2) Post-tensioning prestressed technology: First, cast non-prestressed concrete components, and after hardening, tension and grouting are performed. Special tensioning equipment and grouting operation are required. The technical requirements for construction personnel are high. Incomplete grouting can easily lead to corrosion of prestressed tendons and reduced durability. Utility Model Content
[0006] This utility model proposes a sliding mold for the production of prestressed concrete mandrels. Through the cooperation of U-shaped channel steel and head guide mechanism, it realizes efficient and continuous production of prestressed concrete mandrels while ensuring product quality.
[0007] This utility model is implemented as follows: a sliding mold for producing prestressed concrete mandrels, comprising:
[0008] The main body of the channel steel has a U-shaped cross section, with the opening of the main body facing downwards and a grouting hole provided at the top of the main body.
[0009] A tail-fixing steel plate is attached to the tail of the channel steel body, and two symmetrically distributed prestressed tendon perforations are opened on the outer wall of the tail-fixing steel plate.
[0010] A cleaning port is provided at the top of the channel steel body and is connected to the channel steel body. The cleaning port is located at the front end of the grouting hole.
[0011] The head guide mechanism includes a first guide steel plate and a second guide steel plate. The first guide steel plate is detachably connected to the front end of the channel steel body by bolts and is located behind the cleaning port. The second guide steel plate is fixed to the head end face of the channel steel body.
[0012] As a preferred sliding mold for producing prestressed concrete mandrels according to this utility model, both the first guide steel plate and the second guide steel plate have two symmetrically distributed through holes, and the through holes are coaxially arranged with the prestressing tendon through holes.
[0013] As a preferred sliding mold for producing prestressed concrete mandrels according to this utility model, the main body of the channel steel is No. 8 standard channel steel, and the inner wall is plated with a hard chrome layer with a thickness of 0.05 to 0.1 mm.
[0014] As a preferred sliding mold for producing prestressed concrete mandrels according to this utility model, the inner wall of the channel steel body is made of hard chrome plating to achieve wear resistance, and the plating thickness is 0.05-0.1mm.
[0015] As a preferred sliding mold for producing prestressed concrete mandrels according to this utility model, the tail fixing steel plate has a thickness of 10-12mm and is made of Q235 steel.
[0016] The beneficial effects of this utility model are:
[0017] 1. By simultaneously sliding the channel steel and grouting, continuous and uninterrupted production is achieved, which effectively improves the working efficiency compared to traditional fixed molds. Furthermore, the sliding demolding and prestress release are completed simultaneously, reducing manual intervention.
[0018] 2. By using the U-shaped channel steel with its opening facing downwards, combined with the guiding constraints of the through holes of the first and second guide steel plates and the perforations of the prestressing tendons, the channel steel can be prevented from shifting and the prestressing tendons can be avoided from being eccentric. At the same time, the overflowing concrete can be removed in real time through the cleaning port to ensure the flatness of the end face and guarantee product quality. Attached Figure Description
[0019] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.
[0020] Figure 1 This is an overall structural diagram of a sliding mold for producing prestressed concrete mandrels according to this utility model.
[0021] Figure 2 This is a structural diagram of the channel steel body, the first guide steel plate, and the second guide steel plate of this utility model.
[0022] Figure 3 This is a structural diagram of the second guide steel plate of this utility model.
[0023] Figure 4This is a cross-sectional structural diagram of the mandrel after molding according to this utility model.
[0024] The markings in the diagram are: 1. Channel steel body; 2. Grouting hole; 3. Tail fixing steel plate; 301. Prestressed tendon perforation; 4. Cleaning port; 5. First guide steel plate; 6. Second guide steel plate; 601. Through hole. Detailed Implementation
[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments to aid in understanding its content. Unless otherwise specified, the methods used in this invention are conventional methods; the raw materials and apparatus used, unless otherwise specified, are conventional commercially available products.
[0026] Please see Figure 1-4 A sliding mold for producing prestressed concrete mandrels, comprising:
[0027] The U-shaped cross-section channel steel body 1 has an opening facing downwards, and a grouting hole 2 is provided at the top of the channel steel body 1;
[0028] Tail-fixed steel plate 3 is attached to the tail of the channel steel body 1, and two symmetrically distributed prestressed tendon through holes 301 are opened on the outer wall of the tail-fixed steel plate 3.
[0029] Cleaning port 4 is opened at the top of the channel steel body 1 and is connected to the channel steel body 1. Cleaning port 4 is located at the front end of grouting hole 2.
[0030] The head guide mechanism includes a first guide steel plate 5 and a second guide steel plate 6. The first guide steel plate 5 is detachably connected to the front end of the channel steel body 1 by bolts and is located behind the cleaning port 4. The second guide steel plate 6 is fixed to the head end face of the channel steel body 1.
[0031] In this embodiment: two prestressed spiral rib steel wires are sequentially passed through the prestressed tendon through hole 301 of the tail fixing steel plate 3, the through hole 601 of the first guide steel plate 5 and the second guide steel plate 6, and a preset tension force is applied to the steel wires to make them straight. Low slump dry hard concrete is injected into the U-shaped cavity of the channel steel body 1 through the grouting hole 2. When the channel steel is stationary, the concrete fills the tail area under the action of gravity. By uniformly pulling the channel steel body 1 along the direction of the prestressed tendon and continuously injecting new concrete, a continuous production of "front demolding - middle forming - rear grouting" is formed, thereby realizing the efficient continuous production of mandrels.
[0032] Meanwhile, when the channel steel body 1 moves, the through hole 601 and the prestressing tendon through hole 301 are coaxially set, which can constrain the lateral displacement of the channel steel, ensure that the sliding trajectory coincides with the axis of the prestressing tendon, and the tail fixing steel plate 3 provides rigid support to suppress the tail shaking when sliding starts. In addition, during the grouting process, concrete may overflow from the gap between the first guide steel plate 5 and the channel steel body 1. Through the cleaning port 4, the operator can scrape off the excess grout in real time to ensure the flatness of the mandrel end face and ensure the quality of prestressed concrete mandrel production.
[0033] As a technical optimization of this utility model, two symmetrically distributed through holes 601 are provided on the first guide steel plate 5 and the second guide steel plate 6, and the through holes 601 are coaxially arranged with the prestressing tendon through holes 301.
[0034] In this embodiment: the through holes 601 on the first guide steel plate 5 and the second guide steel plate 6 are strictly coaxial with the prestressing tendon through holes 301 on the tail fixed steel plate 3, ensuring that the two prestressing tendons (steel wires) are always in a parallel state. When the channel steel body 1 slides along the prestressing tendon, the gap between the through holes 601 and the prestressing tendon forms a mechanical limit to prevent the channel steel from shifting laterally.
[0035] As a technical optimization of this utility model, the main body 1 of the channel steel is a No. 8 standard channel steel, and the inner wall is plated with a hard chrome layer with a thickness of 0.05 to 0.1 mm.
[0036] In this embodiment, the U-shaped cross-section of the No. 8 standard channel steel is matched with the spatial distribution of the two 6mm diameter prestressed tendons to ensure that the thickness of the concrete wrapping layer is ≥15mm.
[0037] As a technical optimization of this utility model, the inner wall of the channel steel body 1 is made wear-resistant by hard chrome plating, and the plating thickness is 0.05-0.1mm.
[0038] In this embodiment: a hard chrome plating process is used to form a dense chrome layer with a thickness of 0.05 to 0.1 mm on the inner wall of the channel steel. The non-stick surface of the plating reduces the chemical adsorption force between the concrete and the mold, making the sliding demolding smoother.
[0039] As a technical optimization of this utility model, the tail fixing steel plate 3 has a thickness of 10-12mm and is made of Q235 steel.
[0040] In this embodiment: the tail fixing steel plate 3 is a Q235 steel plate with a thickness of 10-12mm, which can withstand the instantaneous impact force (≥5kN) when the towing starts, suppress tail vibration, and the thickness of the steel plate provides sufficient bending stiffness to evenly transfer the dragging force to the channel steel body 1 and avoid local deformation.
[0041] The working principle and usage process of this utility model are as follows: In use, two 6mm diameter prestressed spiral rib steel wires are sequentially passed through the prestressing tendon perforation 301 of the tail fixing steel plate 3, and the through holes 601 of the first guide steel plate 5 and the second guide steel plate 6. A preset tension force (≥70% ultimate strength, i.e., ≥1100MPa) is applied to the steel wires, taut and anchored at both ends of the production line to form a straight reference. External force is used to make the tail fixing steel plate 3 abut against the tail end of the channel steel body 1. Low-slump dry-hard concrete (slump ≤30mm) is then injected into the U-shaped cavity of the channel steel body 1 through the grouting hole 2. When the channel steel is stationary, the concrete fills the tail area (tail fixing steel plate 3) under gravity. Between plate 3 and the first guide steel plate 5, the main body of the channel steel 1 is pulled at a constant speed along the direction of the prestressed tendons (head direction) by starting the dragging device (such as a winch), and new concrete is continuously injected to form a continuous production of "front demolding - middle forming - rear grouting". The front end of the pre-cured mandrel (near the tail fixed steel plate 3) gradually detaches from the mold as the channel steel moves forward and enters the natural curing stage. Concrete is continuously injected into the tail of the channel steel to form a continuous mandrel. The grouting speed (the amount of concrete injected per unit time) must be strictly matched with the sliding speed (the channel steel moving speed) to ensure that the concrete filling rate in the cavity is always maintained at 95% to 100%, so that the concrete distribution in the main body of the channel steel 1 is uniform.
[0042] When the channel steel body 1 moves, the through hole 601 and the prestressing tendon through hole 301 are coaxially set, which can constrain the lateral displacement of the channel steel and ensure that the sliding trajectory coincides with the axis of the prestressing tendon. The tail fixing steel plate 3 provides rigid support to suppress the tail shaking when sliding starts. During the grouting process, concrete may overflow from the gap between the first guide steel plate 5 and the channel steel body 1. Through the cleaning port 4, the operator can scrape off the excess grout in real time to ensure the flatness of the mandrel end face. The formed mandrel is covered with wet burlap in the static area of the production line for curing, and the humidity is kept ≥90% until the concrete strength reaches more than 70% of the design value (about 24 to 48 hours). The prestressing tendon tension is released in stages using hydraulic jacks. The retraction of the tendon transfers the prestress to the mandrel. After the tension is fully released, the prestressed concrete mandrel with a rectangular cross section is obtained by demolding.
[0043] In the description of this utility model, it should be understood that the terms "left", "right", "up", "down", "top", "bottom", "front", "back", "inner", "outer", "back", "middle", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0044] However, the above description is only a specific embodiment of this utility model and should not be construed as limiting the scope of implementation of this utility model. Therefore, any substitution of equivalent components or equivalent changes and modifications made in accordance with the scope of protection of this utility model should still fall within the scope of the claims of this utility model.
Claims
1. A sliding mold for prestressed concrete core rod production, characterized by, include: The U-shaped cross-section channel steel body (1) has an opening facing downwards, and a grouting hole (2) is provided on the top of the channel steel body (1). Tail-fixed steel plate (3) is attached to the tail of the channel steel body (1), and the outer wall of the tail-fixed steel plate (3) has two symmetrically distributed prestressed tendon through holes (301). Cleaning port (4) is opened at the top of the channel steel body (1) and communicates with the channel steel body (1). The cleaning port (4) is located at the front end of the grouting hole (2). The head guide mechanism includes a first guide steel plate (5) and a second guide steel plate (6). The first guide steel plate (5) is detachably connected to the front end of the channel steel body (1) by bolts and is located behind the cleaning port (4). The second guide steel plate (6) is fixed to the head end face of the channel steel body (1).
2. The sliding mold for producing a prestressed concrete core rod according to claim 1, characterized in that: The first guide steel plate (5) and the second guide steel plate (6) each have two symmetrically distributed through holes (601), and the through holes (601) are coaxially arranged with the prestressing tendon through holes (301).
3. The sliding mold for producing a prestressed concrete core rod according to claim 1, characterized in that: The main body of the channel steel (1) is a No. 8 standard channel steel with a hard chrome plating layer thickness of 0.05 to 0.1 mm on the inner wall.
4. The sliding mold for producing a prestressed concrete core rod according to claim 1, characterized in that: The inner wall of the channel steel body (1) is made wear-resistant by hard chrome plating, with a plating thickness of 0.05 to 0.1 mm.
5. The sliding mold for producing a prestressed concrete core rod according to claim 1, characterized in that: The tail fixing steel plate (3) has a thickness of 10-12mm and is made of Q235 steel.