CN204403609U - A kind of steel plastic compount screw thread bellows - Google Patents

Abstract

The utility model relates to a steel-plastic composite thread corrugated pipe. The outer side of the steel-plastic composite thread corrugated pipe has a corrugated thread structure. Adhesive layer, steel belt layer, second adhesive layer, reinforcement layer, plastic inner layer. The steel-plastic composite threaded corrugated pipe of the utility model has strong compressive capacity and high pipe ring stiffness: due to the steel-plastic composite and polyethylene or polypropylene reinforced layer solid structure, the compressive capacity and ring stiffness of the pipe can be significantly improved. It can reach more than 16kN/㎡. The steel-plastic composite threaded corrugated pipe of the utility model has good corrosion resistance: the steel strip is covered layer by layer, and other arbitrary substances cannot leak into the steel strip at all, which greatly protects the steel strip and ensures that it will not be corroded.

Description

A steel-plastic composite thread corrugated pipe

technical field

The utility model relates to a thread corrugated pipe, in particular to a steel-plastic composite thread corrugated pipe.

Background technique

The existing HDPE structural wall thermal winding pipe (carat pipe) has the following disadvantages: First, the cost of the pipe is high: because it is made of all-plastic material, when a certain ring stiffness is reached, the amount of material used will increase significantly, and the plastic The price of the material itself is relatively expensive, so the cost of comprehensive materials is relatively high, which is about 30% higher than that of ordinary steel-plastic composite pipes. Second, it is impossible to produce super-large-diameter pipes: due to the all-plastic material, when producing large-diameter pipes, its compressive performance decreases in a three-dimensional manner. Therefore, it is impossible to produce pipes with a diameter of more than 3 meters, which is the biggest limitation of this product. . Third, the ring stiffness of the pipe is low: because it is made of all-plastic material, affected by the small bending modulus of the plastic itself, its compressive performance is low, and the ring stiffness is generally about 8kN/㎡.

The existing steel belt reinforced polyethylene (PE) spiral corrugated pipe for buried drainage has the following disadvantages: First, the ring stiffness is low: although the pipe adopts the steel-plastic composite method, due to structural defects, its waveform is inverted " The U" shape is hollow, and the compressive strength is still insufficient, generally within 12.5kN/㎡. Second, the corrosion resistance is poor: Although the steel strip has been treated with plastic coating on the surface, because the plastic coating itself is thin, generally about 1mm, if water flows into it during the production process or engineering application, it will be an inverted "U" In the waveform of the hollow structure, after a certain period of time, it is very easy to cause the separation of the plastic coating layer and the steel strip, and finally cause the corrosion of the steel strip and cause engineering accidents. Third, the mutual coverage between steel and plastic is poor: due to the inverted "U"-shaped hollow corrugated structure, nearly 40% of the area of the steel strip is not covered by the plastic layer, resulting in uneven force transmission when subjected to external forces, which is easy to Local stress concentration occurs, thereby destroying the pipeline and causing engineering accidents. Fourth, poor environmental adaptability: Due to the inverted "U"-shaped hollow corrugated structure, the steel and plastic are not fully covered. Under the influence of the external ambient temperature, the side that is not fully covered is prone to produce gaps between the steel and plastic due to thermal expansion and contraction. The separation between them will destroy the reinforcing effect of the steel strip and greatly reduce the anti-corrosion effect of the plastic layer on the steel strip. Fifth, the service life is short: due to structural defects, the problem of steel-plastic composite is not well overcome, and the steel-plastic separation phenomenon often occurs after a certain period of time, and the service life is generally about 10 years.

Utility model content

The purpose of the utility model is to provide a steel-plastic composite threaded corrugated pipe and its manufacturing method to overcome the low rigidity of the ring of the spiral corrugated pipe in the prior art, poor corrosion resistance, poor cladding between steel and plastic, and long service life. short question.

The utility model adopts the following technical scheme: a steel-plastic composite threaded corrugated pipe, the outer side of the steel-plastic composite threaded corrugated pipe is thread-shaped, the protruding threads on the outer side of the steel-plastic composite threaded corrugated pipe are crests, and the steel-plastic composite threaded corrugated pipe The outer side of the threaded corrugated pipe is recessed relative to the wave crest. The wave crest of the steel-plastic composite threaded corrugated pipe is provided with a plastic outer layer, a first adhesive layer, a steel belt layer, and a second adhesive layer in sequence from the outside to the inside. layer, a reinforced layer, and an inner plastic layer, the cross section of the plastic outer layer is in an inverted "U" shape, the cross section of the steel strip layer is in an inverted "U" shape, and the steel strip layer and the plastic outer layer pass through the The first adhesive layer is bonded, the cross-sectional shape of the reinforced layer is adapted to the cross-sectional shape of the steel belt layer, and the reinforced layer is filled in the inverted "U" shape formed by the steel belt layer , the reinforcement layer is bonded to the steel belt layer through a second adhesive layer, and the bottom of the reinforcement layer is connected to the plastic inner layer.

Preferably, the trough of the steel-plastic composite threaded corrugated pipe includes the plastic outer layer and the plastic inner layer, and the plastic outer layer is connected to the plastic inner layer.

Preferably, the reinforced layer is a polyethylene reinforced layer or a polypropylene reinforced layer.

Preferably, the plastic outer layer is a polyethylene outer layer or a polypropylene outer layer.

Preferably, the plastic inner layer is a polyethylene inner layer or a polypropylene inner layer.

The above description of the structure and method of the utility model shows that compared with the prior art, the utility model has the following advantages: First, the steel-plastic composite thread bellows of the utility model has strong compressive capacity and high pipe ring rigidity: due to the use of The solid structure of steel-plastic composite and polyethylene or polypropylene reinforced layer can significantly improve the compressive capacity of the pipe, and the ring stiffness can reach more than 16kN/㎡. Second, the steel-plastic composite threaded corrugated pipe of the present invention has excellent toughness: polyethylene or polypropylene plastics are used to make good use of their toughness characteristics, and their elongation can reach more than 300%. At the same time, they have good low-temperature performance and can Normal use at -20°C. Third, the steel-plastic composite threaded corrugated pipe of the present invention has good corrosion resistance: the steel strip is coated layer by layer, and other arbitrary substances cannot leak into the steel strip at all, which greatly protects the steel strip and ensures that it will not be corroded. Fourth, the pipe internal stress of the steel-plastic composite thread corrugated pipe of the utility model is small: compared with other steel-plastic composite pipes, the steel-plastic composite spiral corrugated pipe has no hollow space in the corrugation due to the full contact between the plastic and the steel belt, so the plastic and steel The cladding of the belt is better, and when subjected to external force, it will form a good steel-plastic interaction, and evenly transmit the force to each structural layer, which greatly overcomes the stress concentration problem of the steel belt and plastic. Fifth, the pipe has good environmental adaptability: compared with other steel-plastic composite pipes, because the steel strip is deeply embedded in the plastic layer, it has good compatibility with the plastic. Under the influence of the external environment temperature, the steel strip will The thermal expansion and contraction of the plastic produces the corresponding displacement as much as possible, unlike other steel-plastic composite pipes, because nearly half of the area of the steel belt is not covered, resulting in the difference in the shrinkage rate of the steel and plastic under the influence of the external environment temperature , It is easy to cause the steel and plastic to detach after long-term thermal expansion and cold contraction, which greatly reduces the reinforcing effect of the steel strip, and at the same time, the anti-corrosion effect of the plastic layer on the steel strip is also greatly reduced. Sixth, the cost of the steel-plastic composite threaded corrugated pipe of the present invention is low: Compared with the all-plastic pipe, the steel-plastic composite spiral corrugated pipe uses a steel belt layer, and when the same ring stiffness is achieved, the material usage of the pipe can be significantly reduced. (Taking pipes with a DN800 ring stiffness of 16kN/㎡ as an example, the steel-plastic composite spiral corrugated pipe weighs about 35kg/m2), and at the same time, compared with plastics, steel belts are also cheaper, so the overall cost can be reduced by more than 40%. , and the best all-plastic pipes on the market at present, such as HDPE structural wall thermal winding pipes (carat pipes), because they are all made of plastic, the bending modulus of the material is low, so the amount of material is greatly increased, and its DN800 ring stiffness is The weight of 8kN/㎡ pipe meter needs to be more than 60kg/m, and the price of plastic material is more expensive than steel belt, so the overall cost is greatly increased. Seventh, the utility model can produce super-large-diameter steel-plastic composite threaded corrugated pipes: due to the effective application of steel strips, the ring stiffness of the pipes can still be ensured when producing super-large-diameter pipes, meeting the requirements of some key projects. Eighth, the steel-plastic composite threaded corrugated pipe of the present invention has a long service life: the overall structure of the pipe is excellent, which perfectly integrates the characteristics of steel strip and plastic, greatly overcomes their respective congenital defects, and makes the plastic and steel strip The performance is organically unified, and the service life of the pipe can reach more than 50 years.

Description of drawings

Fig. 1 is a schematic cross-sectional structure diagram of the steel-plastic composite thread corrugated pipe of the present invention, in which only part of the pipe section of the steel-plastic composite thread corrugated pipe is shown.

FIG. 2 is a schematic diagram of an enlarged structure of A in FIG. 1 .

Fig. 3 is a schematic diagram of the wave crest decomposition structure of the steel-plastic composite thread corrugated pipe of the present invention.

Detailed ways

The specific embodiment of the utility model is described below with reference to accompanying drawing.

Referring to Figure 1 and Figure 2, a steel-plastic composite threaded corrugated pipe, the outer side of the steel-plastic composite threaded bellows is threaded, the outer raised thread of the steel-plastic composite threaded The concave position on the outer side of the corrugated pipe relative to the crest 1 is the trough 2, and the crest 1 of the steel-plastic composite threaded corrugated pipe is provided with a plastic outer layer 10, a first adhesive layer 11, and a steel belt layer 12 in sequence from the outside to the inside. , the second adhesive layer 13 , the reinforcement layer 14 , and the plastic inner layer 15 . The cross section of the plastic outer layer 10 is in an inverted "U" shape, and the cross section of the steel strip layer 12 is in an inverted "U" shape. The steel strip layer 12 is bonded to the plastic outer layer 10 through the first adhesive layer 11 . The cross-sectional shape of the reinforced layer 14 is adapted to the cross-sectional shape of the steel belt layer 12 , and the reinforced layer 14 is filled in the inverted "U" shape formed by the steel belt layer 12 . The reinforced layer 14 is bonded to the steel strip layer 12 through the second adhesive layer 13 , and the bottom of the reinforced layer 14 is connected to the plastic inner layer 15 .

Referring to Figures 1 and 2, the trough 2 of the steel-plastic composite threaded corrugated pipe includes two plastic outer layers 10 and two plastic inner layers 15, and the plastic outer layer 10 and the plastic inner layer 15 are superimposed on each other. The reinforced layer 14 is a polyethylene reinforced layer or a polypropylene reinforced layer. The plastic outer layer 10 is a polyethylene outer layer or a polypropylene outer layer. The plastic inner layer 15 is a polyethylene inner layer or a polypropylene inner layer.

A method for manufacturing a steel-plastic composite threaded bellows, the method comprising the following steps:

First, the production of plastic-coated steel strips includes the following steps:

A. Melt the adhesive with oxygen barrier and anti-corrosion properties at a temperature of 160-230°C;

B. Heating the steel strip to be coated with plastic to 200-300°C and keeping it warm, so that the overall heating of the steel strip is uniform and ensures a good plastic-coated bonding effect;

C. Apply the adhesive evenly on the surface of the heated steel strip;

D. Use cooling water with a temperature of 30-60°C to cool down the plastic-coated steel strip that has been coated;

E. Pull out the plastic-coated steel strip at a constant speed of 0.5-8m/min.

F. Roll the coated plastic-coated steel strip into a coil.

Second, the production of the reinforced layer 14 comprises the following steps:

a. Melting polyethylene or polypropylene particles at a temperature of 170-250°C.

b. Pass polyethylene or polypropylene melt through a mold to form the shape of the reinforced layer.

c. Pass the polyethylene or polypropylene reinforced layer through a sizing sleeve and cooling water at a temperature of 30-60°C for cooling and shaping to make it cool and solidify.

d. Pull out the polyethylene or polypropylene reinforced layer at a constant speed of 0.5-8m/min.

e. Roll the polyethylene or polypropylene reinforced layer that has been cooled and shaped into a roll.

Third, manufacture steel-plastic composite threaded bellows, including the following steps:

(1) Form the plastic-coated steel strip into a corrugated structure, and heat the surface of the formed plastic-coated steel strip to 120-180°C;

(2) Heat the polyethylene or polypropylene reinforced layer to 150-220°C, and compound the heated plastic-coated steel strip and the heated polyethylene or polypropylene reinforced layer into a steel-plastic composite reinforced layer, and pass through The bending machine bends to form a circle;

(3) Extrude the inner layer of polyethylene or polypropylene and lead it to the winding machine, and make it spiral forward with the winding machine to form the inner layer of the pipe;

(4) Heat the circle-shaped steel-plastic composite reinforcement layer to 150-220°C, introduce it into the winding machine, and compound it with the inner layer of polyethylene or polypropylene;

(5) Extrude the outer layer of polyethylene or polypropylene, and wrap it on the tightly bonded steel-plastic composite reinforcement layer and the inner layer of polyethylene or polypropylene, and finally wrap the polypropylene through the spiral movement of the winding machine. The outer layer of ethylene or polypropylene, the steel-plastic composite reinforced layer, and the inner layer of polyethylene or polypropylene are closely combined; after the outer layer of polyethylene or polypropylene is wound by spiral, the polyethylene or polypropylene between two adjacent peaks of the pipe The outer layers of propylene are superimposed on each other to form the outer part of the trough of the pipe, and the outer part of the trough of the pipe is superimposed with the inner layer of the pipe;

(6) Cool and solidify the composited layers to form the final steel-plastic composite spiral corrugated pipe.

The steel-plastic composite threaded corrugated pipe of the utility model has strong compressive capacity and high rigidity of the pipe ring: due to the use of steel-plastic composite, the characteristics of high bending modulus of steel (bending modulus of steel can reach about 200Gpa, while polyethylene or polyethylene The flexural modulus of propylene is about 1Gpa), which can effectively improve the compressive capacity of steel-plastic composite threaded bellows. The solid structure of polyethylene or polypropylene reinforced layer is adopted. Because the corrugated thread is a solid structure of inner reinforcement, the compressive capacity of the pipe can be significantly improved, and the ring stiffness can reach more than 16kN/㎡. The steel-plastic composite threaded bellows of the utility model has excellent toughness: polyethylene or polypropylene plastics are used, and their toughness is excellently utilized, and their elongation rate can reach more than 300%. Normal use under the condition of ℃. The steel-plastic composite threaded corrugated pipe of the utility model has good corrosion resistance: the steel strip is covered layer by layer, and other arbitrary substances cannot leak into the steel strip at all, which greatly protects the steel strip and ensures that it will not be corroded. The steel-plastic composite thread corrugated pipe of the utility model has small internal stress: compared with other steel-plastic composite pipes, the steel-plastic composite spiral corrugated pipe has no hollow space due to the full contact between the plastic and the steel strip, so the plastic and steel strip Better coverage, when subjected to external force, it will form a good steel-plastic interaction, and evenly transmit the force to each structural layer, which greatly overcomes the stress concentration problem of steel belt and plastic. The pipe has good environmental adaptability: compared with other steel-plastic composite pipes, because the steel strip is deeply buried in the plastic layer, it has good compatibility with the plastic. Expansion and contraction produce corresponding displacement as much as possible, unlike other steel-plastic composite pipes, because nearly half of the area of the steel strip is not covered, resulting in the difference in the shrinkage rate of the steel-plastic under the influence of the external environment temperature, which is easy to cause The steel-plastic detachment occurs after long-term thermal expansion and cold contraction, which greatly reduces the reinforcing effect of the steel strip, and at the same time, the anti-corrosion effect of the plastic layer on the steel strip is also greatly reduced. The steel-plastic composite threaded corrugated pipe of the utility model has low cost: compared with the all-plastic pipe, the steel-plastic composite spiral corrugated pipe uses a steel belt layer, and when the same ring stiffness is achieved, the material usage of the pipe can be significantly reduced (by DN800 pipe with a ring stiffness of 16kN/㎡ is an example. The steel-plastic composite spiral corrugated pipe weighs about 35kg/m). At the same time, compared with plastic, steel strips are also cheaper, so the overall cost can be reduced by more than 40%. The best all-plastic pipes on the market, such as HDPE structural wall thermal winding pipes (carat pipes), because they are all made of plastic, the material has a low flexural modulus, so the amount of materials is greatly increased, and its DN800 ring stiffness is 8kN/㎡ The weight of the pipe meter needs to be more than 60kg/m, and the price of the plastic material is more expensive than the steel belt, so the overall cost is greatly increased. The utility model can produce ultra-large-diameter steel-plastic composite threaded corrugated pipes: due to the effective application of steel strips, the ring stiffness of the pipes can still be ensured when producing ultra-large-diameter pipes, meeting the requirements of some key projects. The steel-plastic composite threaded corrugated pipe of the utility model has a long service life: the overall structure of the pipe is excellent, which perfectly integrates the characteristics of the steel strip and the plastic, greatly overcomes their respective congenital defects, and makes the performance of the plastic and the steel strip organic. Unified, the service life of the pipe can reach more than 50 years.

The above is only a specific embodiment of the utility model, but the design concept of the utility model is not limited thereto, and any non-substantial modification of the utility model by using this concept should be an act of violating the protection scope of the utility model.

Claims (5)

1. A steel-plastic composite threaded corrugated pipe, characterized in that: the outer side of the steel-plastic composite threaded corrugated pipe is helical, the protruding threads on the outer side of the steel-plastic composite threaded corrugated pipe are crests, and the steel-plastic composite threaded corrugated pipe The outer side of the pipe is recessed relative to the wave crest. The wave crest of the steel-plastic composite thread corrugated pipe is provided with a plastic outer layer, a first adhesive layer, a steel belt layer, a second adhesive layer, Reinforced layer, plastic inner layer, the cross-section of the plastic outer layer is an inverted "U" shape, the cross-sectional shape of the steel belt layer is an inverted "U" shape, the steel belt layer and the plastic outer layer pass through the first Adhesive layer bonding, the cross-sectional shape of the reinforced layer is adapted to the cross-sectional shape of the steel strip layer, and the reinforced layer is filled in the inverted "U" shape formed by the steel strip layer, the The reinforcement layer is bonded to the steel strip layer through the second adhesive layer, and the bottom of the reinforcement layer is connected to the plastic inner layer. 2. A steel-plastic composite thread corrugated pipe according to claim 1, characterized in that: the trough of the steel-plastic composite thread corrugated pipe includes the plastic outer layer and the plastic inner layer, and the plastic outer layer and the plastic inner layer The plastic inner layer is connected. 3. A steel-plastic composite threaded corrugated pipe according to claim 1, characterized in that: said reinforced layer is polyethylene reinforced layer or polypropylene reinforced layer. 4. A steel-plastic composite threaded corrugated pipe according to claim 1 or 2, wherein the plastic outer layer is polyethylene outer layer or polypropylene outer layer. 5. A steel-plastic composite threaded corrugated pipe according to claim 1 or 2, characterized in that: the plastic inner layer is a polyethylene inner layer or a polypropylene inner layer.