A specification for electric-fusion-welded steel pipe for atmospheric and lower temperatures is ASTM A671 Grade CC65. This norm, laid out by ASTM Global, covers a scope of steel pipes intended for different modern applications, especially those including moderate to low temperatures. The ASTM A671 Pipe includes a number of grades, each with its own set of requirements and characteristics. Grade CC65 is one of those grades.
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ASTM A671 GR CC65 pipe dimensions:
When choosing and using ASTM A671 GR CC65 pipes, their dimensions play a crucial role. These pipes come in a variety of sizes to meet the needs of different projects. The standard covers both ostensible line size (NPS) assignments and outside distance across (OD) determinations.
1.Nominal Pipe Size (NPS):
The NPS of ASTM A671 GR CC65 pipes typically ranges from 16 to 150. System design flexibility is made possible by this extensive range, which can accommodate a variety of flow rates and pressure requirements. It is essential to keep in mind that, particularly with larger diameters, the actual outside diameter of the pipe may slightly differ from the nominal size.
2.Outside Diameter (OD):
The outside diameter of ASTM A671 GR CC65 pipes generally ranges from 16 inches (406.4 mm) to 150 inches (3810 mm). This broad range of diameters makes these pipes suitable for a variety of applications, from moderate-sized process piping to large-diameter transmission lines.
3.Wall Thickness:
The wall thickness of the GR CC65 pipes can vary significantly based on the specific application requirements. The standard allows for a range of wall thicknesses, typically starting from 0.25 inches (6.35 mm) and going up to several inches for large-diameter, high-pressure applications.
4.Length:
ASTM A671 GR CC65 pipes are typically supplied in lengths ranging from 20 to 60 feet (6 to 18 meters). However, custom lengths can often be ordered to meet specific project requirements. Longer lengths can reduce the number of field welds required during installation, potentially lowering overall project costs and improving system integrity.
5.Tolerances:
The A671 specification provides specific tolerances for various dimensional aspects of the pipe, including:
1. Outside diameter: Typically ±1% of the specified OD for sizes up to 24 inches, with different tolerances for larger sizes.
2. Wall thickness: Generally, -12.5% of the nominal wall thickness, with no upper limit specified.
3. Length: Usually ±1 inch (25.4 mm) for specified lengths up to 30 feet, with different tolerances for longer pipes.
4. End Finish:
ASTM A671 pipes are typically supplied with square cut ends suitable for welding. However, other end preparations, such as beveled ends for specific welding procedures, can be specified when ordering.
ASTM A671 GR CC65 pipe minimum yield strength:
The GR CC65 pipes' capacity to withstand stress without permanent deformation is determined by the minimum yield strength, a crucial property. In situations where the pipe may be subjected to significant internal pressure or external loads, this property is especially crucial.
The minimum yield strength for ASTM A671 GR CC65 pipes is specified as 65,000 psi (448 MPa). This worth addresses the pressure at which the material starts to twist plastically, meaning it won't get back to its unique shape when the pressure is taken out.
The term "carbon steel for moderate and lower temperature service" is spelled "CC" in the grade name, and "65" stands for the minimum yield strength in thousands of pounds per square inch. This yield strength places GR CC65 in the center scope of the grades covered by the A671 detail, offering a decent harmony among strength and other helpful properties.
ASTM A671 GR CC65 pipe testing requirements:
In order to guarantee the quality, dependability, and conformance of Grade CC65 pipes with the standard, extensive testing requirements are outlined in the ASTM A671 specification. The purpose of these tests is to check the pipes' mechanical properties, dimensional precision, and overall integrity. To ensure that the pipes meet the necessary standards for their intended applications, it is essential for manufacturers, quality control personnel, and end users to comprehend these testing requirements.
The key testing requirements for ASTM A671 GR CC65 pipes include:
1. Tensile Testing:
Tensile tests are conducted to verify the mechanical properties of the pipe material. For GR CC65, the test must demonstrate:
- Minimum yield strength of 65,000 psi (448 MPa)
- Minimum tensile strength of 77,000 psi (531 MPa)
- Minimum elongation in 2 inches (50 mm) of 17%
These tests are typically performed on specimens cut from the pipe or from test plates that represent the production material.
2. Chemical Composition Analysis:
The chemical composition of the steel used in GR CC65 pipes must be analyzed and reported. The A671 specification provides limits for various elements, including carbon, manganese, phosphorus, and sulfur. This analysis ensures that the material meets the required grade specifications and helps predict its performance characteristics.
3. Hydrostatic Testing:
Each length of pipe is subjected to a hydrostatic test to verify its pressure-holding capability. The test pressure is calculated based on the pipe dimensions and material properties. For ASTM A671 GR CC65, the test pressure is typically determined using the minimum yield strength of 65,000 psi and applicable safety factors.
4. Nondestructive Examination (NDE):
The welded seam of each pipe must undergo nondestructive examination to detect any potential defects. This typically involves:
- Radiographic testing (RT) or ultrasonic testing (UT) of the entire length of the weld
- Additional examination of the weld ends using RT, UT, or magnetic particle testing (MT)
5. Dimensional Inspection:
The pipes are measured to ensure compliance with the specified dimensions, including outside diameter, wall thickness, and length. Tolerances for these measurements are provided in the A671 specification.
6. Visual Inspection:
A thorough visual inspection is performed to check for surface defects, proper end finishing, and overall appearance of the pipe.
7. Heat Treatment Verification:
If heat treatment is required (which depends on the specific grade and wall thickness), documentation must be provided to verify that the proper heat treatment procedures were followed.
8. Impact Testing:
For pipes intended for low-temperature service, impact testing may be required to ensure adequate toughness at the design minimum temperature. The specific requirements depend on the intended service conditions and are typically specified by the purchaser.
ASTM A671 Pipe Supplier:
While obtaining ASTM A671 pipes, especially Grade CC65, it's vital to work with legitimate makers and providers who can reliably convey excellent items that meet the severe necessities of the detail. One such maker is LONGMA Gathering, which works in delivering ASTM A671 pipes in different grades, including CC60, CC65, and CC70.
LONGMA GROUP welcomes inquiries from customers seeking ASTM A671 pipes, including Grade CC65, at info@longma-group.com. It's a good idea to do thorough research and compare multiple suppliers, just like you would with any major purchase, to make sure you get the best quality and value for your needs.
