Structural self-anticorrosion non-prestressed concrete cylinder pipe and manufacturing method thereof

Abstract

The invention belongs to the technical field of non-prestressed concrete cylinder pipe production, and provides a structural self-anticorrosion non-prestressed concrete cylinder pipe and a manufacturing method thereof. The self-anticorrosion non-prestressed concrete cylinder pipe with the structure comprises a concrete cylinder pipe body, the steel cylinder concrete pipe body is made of a corrosion-resistant material; the corrosion-resistant material comprises a corrosion-resistant concrete material, and the corrosion-resistant concrete material is prepared from the following components in parts by weight: 0.8 to 1.0 part of cement, 0.15 to 0.18 part of active admixture, 0.3 to 0.6 part of fine aggregate, 0 to 1.0 part of coarse aggregate, 0.001 to 0.004 part of admixture and 0.10 to 0.13 part of water. The comprehensive corrosion resistance of the concrete is improved by 10-100 times compared with that of common concrete, and the durability service life of the concrete in various medium and severe corrosion environments can reach 100 years or above under the condition that no other additional corrosion prevention measures are needed. The manufacturing method has the characteristics of convenient production process and stable production quality, and is suitable for large-scale popularization and application.

Description

Technical Field

[0001] The invention belongs to the technical field of non-prestressed steel cylinder concrete pipe production, and in particular relates to a structural self-corrosion-resistant non-prestressed steel cylinder concrete pipe and a manufacturing method thereof. Background Art

[0002] In the field of concrete pressure pipes, there is currently a type of "non-prestressed steel cylinder concrete pipe" (abbreviated as: RCCP), which is widely used in water conservancy, municipal administration, electricity and other related pressure water supply and drainage fields.

[0003] The structure of RCCP pipes includes: an impermeable steel cylinder with a steel socket joint is embedded in the concrete pipe body, and non-prestressed steel bars are arranged in the pipe body inside and outside the impermeable steel cylinder. This type of pipe can be used for jacking construction and installation, and can also be used for slotting and burying pipe construction and installation. The strength grade of the pipe body concrete of this type of pipe is generally C40-C60, and the corrosion resistance is average. When used to transport corrosive media such as sewage and seawater, or when there is a certain degree of corrosiveness in the soil and groundwater, the corrosion resistance of this type of pipe is insufficient, which can seriously affect the actual service life of the pipe, thereby easily resulting in more serious engineering maintenance and reinforcement costs, or shortening the service life of the project, causing adverse social and economic impacts and losses.

[0004] In order to solve the problem of corrosion resistance of pipelines, the industry has adopted a variety of methods, such as setting additional anti-corrosion layers such as PVC, PE, and anti-corrosion coatings on the inner and outer surfaces of the pipelines. These anti-corrosion measures have certain anti-corrosion effects, but because the materials listed above are made of different materials from the concrete pipe body itself, they cannot produce consistent deformation with the concrete pipe body under external forces or environmental effects. In addition, the quality stability is not easy to control. After a period of use, they often develop defects such as cracking and falling off with the concrete pipe body, and cannot achieve the service life required by the engineering design (usually 50 years). Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the first object of the present invention is to provide a structural self-corrosion non-prestressed steel cylinder concrete pipe. The structural self-corrosion non-prestressed steel cylinder concrete pipe has a 28-day cubic compressive strength of not less than 80MPa, a 28-day axial tensile strength of not less than 5.0MPa, a 28-day axial bending strength of not less than 14.0MPa, an impermeability grade higher than P12, and a chloride ion permeability coefficient D RCM No more than 0.8×10 -12 m 2 / s, and the sulfate corrosion resistance level is not less than KS150. Its comprehensive corrosion resistance is 10-100 times higher than that of ordinary concrete. It can fully meet the long-term corrosion resistance requirements in sewage, seawater, and corrosive water and soil environments without any other additional anti-corrosion measures. The durability of this self-corrosion non-prestressed steel cylinder concrete pipe in various moderate and severe corrosion environments can reach more than 100 years.

[0006] In view of the above-mentioned deficiencies in the prior art, the second purpose of the present invention is to provide a method for manufacturing a structural self-corrosion-resistant non-prestressed steel tube concrete pipe, which has the characteristics of convenient production process and stable production quality and is suitable for large-scale promotion and application.

[0007] In order to achieve the above object, the solution adopted by the present invention is:

[0008] A structural self-corrosion-resistant non-prestressed steel cylinder concrete pipe comprises a steel cylinder concrete pipe body; the steel cylinder concrete pipe body is made of corrosion-resistant materials; the corrosion-resistant materials include corrosion-resistant concrete materials, and the corrosion-resistant concrete materials include, by weight: 0.8-1.0 parts of cement, 0.15-0.18 parts of active admixtures, 0.3-0.6 parts of fine aggregates, 0.001-0.004 parts of admixtures and 0.10-0.13 parts of water.

[0009] Furthermore, in a preferred embodiment of the present invention, the corrosion-resistant concrete material further comprises, by weight: less than or equal to 0-1.0 parts of coarse aggregate.

[0010] Furthermore, in a preferred embodiment of the present invention, the corrosion-resistant material also includes fibers; the volume ratio of the fibers to the corrosion-resistant concrete material is 0.001-0.006:1.

[0011] Furthermore, in a preferred embodiment of the present invention, the fibers include stainless steel fibers and non-metallic fibers in a weight ratio of 1:2; the non-metallic fibers include basalt fibers or glass fibers.

[0012] Furthermore, in a preferred embodiment of the present invention, the active admixture includes at least two of fly ash, mineral powder, silica fume, microspheres and expansion agent.

[0013] Furthermore, in a preferred embodiment of the present invention, the fine aggregate includes at least one of quartz sand, natural sand and artificial sand.

[0014] Furthermore, in a preferred embodiment of the present invention, the admixture is an admixture that can reduce water and improve pumping effect.

[0015] Further, in a preferred embodiment of the present invention, the cement grade is higher than or equal to grade 42.5.

[0016] Furthermore, in a preferred embodiment of the present invention, the coarse aggregate includes at least one of artificial crushed stone and quartz crushed stone having a maximum particle size of less than or equal to 16 mm.

[0017] A method for manufacturing the above-mentioned self-corrosion-resistant non-prestressed steel cylinder concrete pipe comprises: (1) manufacturing an anti-seepage steel cylinder according to designed dimensions and materials; (2) manufacturing a non-prestressed force-bearing steel skeleton according to designed dimensions and materials; (3) assembling the anti-seepage steel cylinder and the steel skeleton into a combination according to designed positions; (4) loading the combination into a mold; (5) pouring a corrosion-resistant material into the mold and performing natural curing or accelerated curing; (6) removing the mold after the corrosion-resistant material reaches a certain strength to form a finished product.

[0018] The beneficial effects of the structural self-corrosion non-prestressed steel cylinder concrete pipe and the manufacturing method thereof provided by the present invention are:

[0019] (1) The structural self-corrosion-resistant non-prestressed steel cylinder concrete pipe provided by the present invention has a comprehensive corrosion resistance that is 10-100 times higher than that of ordinary concrete. It can fully meet the long-term corrosion resistance requirements in sewage, seawater, and corrosive water and soil environments without the need for any other additional anti-corrosion measures. The structural self-corrosion-resistant non-prestressed steel cylinder concrete pipe using this technology can have a durability of more than 100 years in various moderate and severe corrosion environments.

[0020] The self-corrosion-resistant non-prestressed steel cylinder concrete pipe provided in the present application has a 28-day cubic compressive strength of not less than 80MPa, a 28-day axial tensile strength of not less than 5.0MPa, a 28-day axial bending strength of not less than 14.0MPa, an impermeability grade higher than P12, and an anti-chloride ion permeability coefficient of D RCM No more than 0.8×10 -12 m 2 / s, and the sulfate corrosion resistance grade is not less than KS150.

[0021] (2) The manufacturing method provided by the present invention can be applied to non-prestressed steel tube concrete pipes with an inner diameter ranging from 800mm to 4000mm, and can also be applied to pipes with larger diameters. The length of a single section of the pipe body can be selected from 1m to 6m as needed.

[0022] (3) The manufacturing method provided by the present invention effectively solves the production quality assurance problems such as the cracking and falling-off prevention of the corrosion-resistant additional layer of the structural self-corrosion non-prestressed steel cylinder concrete pipe. Not only can it replace the traditional non-prestressed steel cylinder concrete pipe with excellent corrosion resistance, but also there is no problem of cracking or falling-off of the corrosion-resistant additional layer and the pipe body of the traditional non-prestressed steel cylinder concrete pipe with a corrosion-resistant additional layer under external force or environmental action. In addition, the absence of the need to set the corrosion-resistant additional layer also leads to further simplification of the pipe body structure and production process, which is suitable for large-scale promotion and application. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0024] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0025] Example 1

[0026] This embodiment provides a structural self-corrosion non-prestressed steel cylinder concrete pipe, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant materials and fibers (stainless steel fiber: basalt fiber = 1:2). The corrosion-resistant material includes a corrosion-resistant concrete material, and the corrosion-resistant concrete material includes, by weight: 1.0 part of cement, 0.15 parts of active admixtures (mineral powder: silica fume: microbeads = 2:1:2), 0.6 parts of fine aggregate (quartz sand: natural sand: artificial sand = 1:1:1), 0.004 parts of lignin sulfonate and 0.10 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.003:1.

[0027] This embodiment also provides a method for manufacturing a structural self-corrosion non-prestressed steel cylinder concrete pipe, including: (1) manufacturing an anti-seepage steel cylinder according to designed dimensions and materials; (2) manufacturing a non-prestressed force-bearing steel skeleton according to designed dimensions and materials; (3) assembling the anti-seepage steel cylinder and the steel skeleton into a combination according to the designed position; (4) loading the combination into a mold; (5) pouring a corrosion-resistant material into the mold and performing natural curing or accelerated curing; (6) removing the mold after the corrosion-resistant material reaches a certain strength to form a finished product.

[0028] Example 2

[0029] This embodiment provides a structural self-corrosion non-prestressed steel cylinder concrete pipe, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant materials and fibers (stainless steel fiber: basalt fiber = 1:2). The corrosion-resistant material includes corrosion-resistant concrete materials, and the corrosion-resistant concrete materials include, by weight: 0.8 parts of cement, 0.18 parts of active admixtures (mineral powder: silica fume: microbeads = 2:1:2), 0.3 parts of fine aggregate (quartz sand: natural sand: artificial sand = 1:1:1), 1.0 parts of artificial crushed stone, 0.001 parts of lignin sulfonate and 0.13 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.003:1.

[0030] This embodiment also provides a method for manufacturing a structural self-corrosion-resistant non-prestressed steel tube concrete pipe, please refer to Example 1.

[0031] Example 3

[0032] This embodiment provides a structural self-corrosion non-prestressed steel cylinder concrete pipe, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant materials and fibers (stainless steel fiber: basalt fiber = 1:2). The corrosion-resistant material includes a corrosion-resistant concrete material, and the corrosion-resistant concrete material includes, by weight: 0.9 parts of cement, 0.16 parts of active admixtures (mineral powder: silica fume: microbeads = 2:1:2), 0.5 parts of fine aggregate (quartz sand: natural sand: artificial sand = 1:1:1), 0.5 parts of artificial crushed stone, 0.002 parts of lignin sulfonate and 0.11 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.003:1.

[0033] This embodiment also provides a method for manufacturing a structural self-corrosion-resistant non-prestressed steel tube concrete pipe, please refer to Example 1.

[0034] Example 4

[0035] This embodiment provides a structural self-corrosion non-prestressed steel cylinder concrete pipe, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant materials and fibers (stainless steel fiber: basalt fiber = 1:2). The corrosion-resistant material includes corrosion-resistant concrete materials, and the corrosion-resistant concrete materials include, by weight: 0.9 parts of cement, 0.16 parts of active admixtures (mineral powder: silica fume: microbeads = 2:1:2), 0.5 parts of fine aggregate (quartz sand: natural sand: artificial sand = 1:1:1), 0.5 parts of quartz crushed stone, 0.002 parts of lignin sulfonate and 0.11 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.001:1.

[0036] This embodiment also provides a method for manufacturing a structural self-corrosion-resistant non-prestressed steel tube concrete pipe, please refer to Example 1.

[0037] Example 5

[0038] This embodiment provides a structural self-corrosion non-prestressed steel cylinder concrete pipe, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant materials and fibers (stainless steel fiber: basalt fiber = 1:2). The corrosion-resistant material includes a corrosion-resistant concrete material, and the corrosion-resistant concrete material includes, by weight: 0.9 parts of cement, 0.16 parts of active admixtures (mineral powder: silica fume: microbeads = 2:1:2), 0.5 parts of fine aggregate (quartz sand: natural sand: artificial sand = 1:1:1), 0.5 parts of quartz crushed stone, 0.002 parts of lignin sulfonate and 0.11 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.006:1.

[0039] This embodiment also provides a method for manufacturing a structural self-corrosion-resistant non-prestressed steel tube concrete pipe, please refer to Example 1.

[0040] Example 6

[0041] This embodiment provides a structural self-corrosion non-prestressed steel cylinder concrete pipe, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant materials and fibers (stainless steel fiber: glass fiber = 1:2). The corrosion-resistant material includes corrosion-resistant concrete materials, and the corrosion-resistant concrete materials include, by weight: 0.9 parts of cement, 0.16 parts of active admixtures (ash fly ash: silica ash: microspheres = 2:1:2), 0.5 parts of fine aggregate (quartz sand: natural sand = 1:2), 0.5 parts of coarse aggregate (artificial crushed stone: quartz crushed stone = 1:1), 0.002 parts of lignin sulfonate and 0.11 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.003:1.

[0042] This embodiment also provides a method for manufacturing a structural self-corrosion-resistant non-prestressed steel tube concrete pipe, please refer to Example 1.

[0043] Example 7

[0044] This embodiment provides a structural self-corrosion non-prestressed steel cylinder concrete pipe, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant materials and fibers (stainless steel fiber: glass fiber = 1:2). The corrosion-resistant material includes corrosion-resistant concrete materials, and the corrosion-resistant concrete materials include, by weight: 0.9 parts of cement, 0.16 parts of active admixtures (ash fly ash: silica ash = 2:3), 0.5 parts of quartz sand, 0.5 parts of coarse aggregate (artificial crushed stone: quartz crushed stone = 1:1), 0.002 parts of lignin sulfonate and 0.11 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.003:1.

[0045] This embodiment also provides a method for manufacturing a structural self-corrosion-resistant non-prestressed steel tube concrete pipe, please refer to Example 1.

[0046] Comparative Example 1

[0047] This comparative example provides a common non-prestressed steel cylinder concrete pipe, which uses epoxy coating as an additional anti-corrosion layer, including an epoxy corrosion-resistant coating and a steel cylinder concrete pipe body arranged in sequence from the inside to the outside. The corrosion-resistant coating is an epoxy resin coating material.

[0048] The comparative example also provides a method for manufacturing an ordinary non-prestressed steel cylinder concrete pipe, comprising: (1) manufacturing an anti-seepage steel cylinder according to designed dimensions and materials; (2) manufacturing a non-prestressed force-bearing steel skeleton according to designed dimensions and materials; (3) assembling the anti-seepage steel cylinder and the steel skeleton into a combination according to the designed position; (4) loading the combination into a mold; (5) pouring concrete into the mold and performing natural curing or accelerated curing; (6) removing the mold after the concrete reaches a certain strength to obtain a non-prestressed steel cylinder concrete pipe; and (7) coating the inner wall of the non-prestressed steel cylinder concrete pipe with a corrosion-resistant layer.

[0049] Comparative Example 2

[0050] This comparative example provides a non-prestressed steel cylinder concrete pipe with anti-corrosion performance, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant material and steel fiber. The corrosion-resistant material includes a corrosion-resistant concrete material, and the corrosion-resistant concrete material includes, by weight: 0.5 parts of cement, 0.22 parts of active admixture (mineral powder: silica fume = 2:1), 1.0 parts of quartz sand, 1.5 parts of artificial crushed stone, 0.05 parts of lignin sulfonate and 0.15 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.03:1.

[0051] This comparative example also provides a method for manufacturing a non-prestressed steel cylinder concrete pipe with anti-corrosion performance, please refer to Example 1.

[0052] Comparative Example 3

[0053] This comparative example provides a non-prestressed steel cylinder concrete pipe with anti-corrosion performance, including a steel cylinder concrete pipe body. The steel cylinder concrete pipe body is made of corrosion-resistant material and polypropylene fiber. The corrosion-resistant material includes a corrosion-resistant concrete material, and the corrosion-resistant concrete material includes, by weight: 0.7 parts of cement, 0.36 parts of active admixture (mineral powder: silica fume = 2:1), 1.5 parts of quartz sand, 0.02 parts of lignin sulfonate and 0.11 parts of water. The volume ratio of fiber to corrosion-resistant concrete material is: 0.008:1.

[0054] This comparative example also provides a method for manufacturing a non-prestressed steel cylinder concrete pipe with anti-corrosion performance, please refer to Example 1.

[0055] Experimental Example 1

[0056] Experimental method: The non-prestressed steel cylinder concrete pipes manufactured by the manufacturing methods provided in test examples 1-7 and comparative examples 1-3 were tested for compressive strength at 28 days of age (tested according to the method provided in "GB / T50081 (current version)"), flexural strength at 28 days of age (tested according to the method provided in "T / CECS864 (current version)"), chloride ion permeability coefficient (tested according to the method provided in "GB / T50082 (current version)") (RCM method)), sulfate erosion resistance coefficient (tested according to the method provided in "GB / T50082 (current version)") and tensile strength (tested according to the method provided in "GB / T50081 (current version)"), and impermeability grade (tested according to the method provided in "GB / T50082 (current version)") test results are shown in Table 1.

[0057] Table 1

[0058]

[0059]

[0060] It can be seen from the data in Table 1 that the structural self-corrosion non-prestressed steel cylinder concrete pipe and its manufacturing method provided by Examples 1-7 of the present invention have a 28-day cubic compressive strength of not less than 80 MPa, a 28-day axial tensile strength of not less than 5.0 MPa, a 28-day axial bending strength of not less than 14.0 MPa, an impermeability grade higher than P12, and an anti-chloride ion permeability coefficient D RCM No more than 0.8×10 -12 m 2 / s, and the sulfate corrosion resistance grade is not less than KS150. Compared with the traditional ordinary concrete (28-day cubic compressive strength is not less than 45MPa) used in comparative example 1, the structural self-corrosion non-prestressed steel cylinder concrete pipe provided by the embodiment of the present invention has very excellent corrosion resistance and mechanical properties, and can maintain good working performance for a long time in a moderate or even severe corrosion environment without relying on other anti-corrosion measures.

[0061] At the same time, the data of comparative examples 2 and 3 further illustrate that the structural self-corrosion non-prestressed steel tube concrete pipe prepared within the fiber types provided in Examples 1-7 of the present invention, the components of the corrosion-resistant concrete material and their ratio range, and the ratio range of the corrosion-resistant concrete material and the fiber have more excellent corrosion resistance and mechanical properties.

[0062] In summary, the structural self-corrosion non-prestressed steel cylinder concrete pipe provided by the present invention has a 28-day cubic compressive strength of not less than 80MPa, a 28-day axial tensile strength of not less than 5.0MPa, a 28-day axial bending strength of not less than 14.0MPa, an impermeability grade higher than P12, and an anti-chloride ion permeability coefficient D RCM No more than 0.8×10 -12 m 2 / s, and the sulfate corrosion resistance level is not less than KS150. Its comprehensive corrosion resistance is 10-100 times higher than that of ordinary concrete. It can fully meet the long-term corrosion resistance requirements in sewage, seawater, and corrosive water and soil environments without any other additional anti-corrosion measures. The durability of the structural self-corrosion non-prestressed steel cylinder concrete pipe in various medium and severe corrosion environments can reach more than 100 years. The manufacturing method of the structural self-corrosion non-prestressed steel cylinder concrete pipe provided by the present invention has the characteristics of convenient production process and stable production quality, and is suitable for large-scale promotion and application.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A structural self-corrosion non-prestressed steel cylinder concrete pipe, characterized in that: It includes a concrete cylinder pipe body; The steel cylinder concrete pipe body is made of corrosion-resistant material; the corrosion-resistant material includes corrosion-resistant concrete material, and the corrosion-resistant concrete material includes, by weight: 0.8-1.0 parts of cement, 0.15-0.18 parts of active admixture, 0.3-0.6 parts of fine aggregate, 0.001-0.004 parts of admixture and 0.10-0.13 parts of water.

2. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1 is characterized in that: The corrosion-resistant concrete material further comprises, by weight: less than or equal to 0-1.0 parts of coarse aggregate.

3. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1 is characterized in that: The corrosion-resistant material also includes fibers; the volume ratio of the fibers to the corrosion-resistant concrete material is 0.001-0.006:

1.

4. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1 is characterized in that: The fibers include stainless steel fibers and non-metallic fibers in a weight ratio of 1:2; the non-metallic fibers include basalt fibers or glass fibers.

5. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1 is characterized in that: The active admixture includes at least two of fly ash, mineral powder, silica fume and microspheres.

6. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1 is characterized in that: The fine aggregate includes at least one of quartz sand, natural sand and artificial sand.

7. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1 is characterized in that: The admixture is an admixture that has the effect of reducing water and improving pumping effect.

8. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1 is characterized in that: The cement grade is higher than or equal to grade 42.

5.

9. The structural self-corrosion non-prestressed steel cylinder concrete pipe according to claim 1, characterized in that: The coarse aggregate includes at least one of artificial crushed stone and quartz crushed stone with a maximum particle size of less than or equal to 16 mm.

10. A method for manufacturing a structural self-corrosion non-prestressed steel cylinder concrete pipe according to any one of claims 1 to 9, characterized in that: include: (1) Manufacture the anti-seepage steel cylinder according to the designed size and materials; (2) manufacturing a non-prestressed steel skeleton according to the designed size and material; (3) assembling the anti-seepage steel tube and the steel skeleton into a combination according to the designed position; (4) loading the combination into a mold; (5) pouring the corrosion-resistant material into the mold and performing natural curing or accelerated curing; (6) removing the mold after the corrosion-resistant material reaches a certain strength to form a finished product.

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