Steel pipe inspection services include:
Thickness testing, eddy current testing, corrosion testing, quality testing, roundness testing, corrosion testing, dimensional testing, flaw detection, nondestructive testing, and impact strength testing.

Physical and Chemical Property Inspections
1. Chemical Composition Inspection: This primarily checks whether the carbon, sulfur, and phosphorus content of the steel pipes meet standard requirements.
2. Mechanical properties test: including tensile strength, yield strength, impact toughness, etc. These indicators are directly related to the service life and safety performance of steel pipes.
3. Weld performance inspection: Welding is one of the important processes of steel pipes. It is very important to inspect the strength and reliability of the welds. Generally, weld tensile and bending tests are used.
4. Corrosion performance and wear resistance test: These indicators are mainly used to evaluate the corrosion resistance and wear resistance of steel pipes under specific environmental conditions.

Appearance and Geometric Dimension Inspection
1. Surface Inspection: This primarily checks the surface quality of the steel pipe for defects such as cracks, scars, and bubbles.
2. Dimension inspection: Check whether the outer diameter, wall thickness, length and other parameters of the steel pipe meet the requirements, and also check the straightness and curvature of the steel pipe.
3. Appearance inspection: Check whether the appearance quality and shape of the steel pipe meet the standard requirements.

1. Hot-Dip Galvanizing of Steel Wire
Hot-dip galvanizing of steel wire involves pickling steel and then immersing it in a molten zinc bath for galvanizing. At high temperatures, the steel surface reacts chemically with the zinc solution to form a zinc alloy coating, which provides corrosion protection. The process temperature of hot-dip galvanizing is usually around 450°C, so it can form a coating with a thicker thickness, higher density and better corrosion resistance.

2. Cold-Dip Galvanizing of Steel Wire
Cold-dip galvanizing of steel wire involves electrolytically depositing a zinc coating on the steel surface. The process temperature of cold galvanizing is below 100°C, thus preventing deformation and damage to the steel. However, the coating thickness of cold-dip galvanizing is thinner and its corrosion resistance is slightly inferior to that of hot-dip galvanizing.

1. Corrosion Resistance
Due to the thicker and denser coating of hot-dip galvanizing, it offers better corrosion resistance. Under the same environment, hot-dip galvanized coating has a longer service life.

2. Cost
Cold-dip galvanizing of steel wire is relatively inexpensive because the process is simpler than hot-dip galvanizing. However, since the coating of cold-dip galvanizing is thinner, hot-dip galvanizing is required in some special occasions to obtain better anti-corrosion effect.

3. Appearance
Hot-dip galvanizing produces a smoother and more uniform coating than cold-dip galvanizing, resulting in a more aesthetically pleasing finish. However, in some cases, cold-dip galvanizing may provide a better surface treatment.

Carbon steel pipe is composed of an iron and carbon alloy, allowing it to be bent and shaped during the manufacturing process without losing its high tensile strength. Protecting the steel surface from corrosion is crucial, as the ferrite component oxidizes and rusts when in contact with water. Pipes supplying fire sprinkler systems are often made of carbon steel, while essential strength components in aircraft and automobiles, such as camshafts and crankshafts, utilize carbon steel pipe and tubing. Effectively protecting carbon steel pipe from corrosion requires the use of the correct primer and paint.

Painting Carbon Steel Pipe
1. Use steel wool to remove all surface rust from the carbon steel pipe. Use a hand brush to remove all rust particles, keeping the work area dust-free.
2. Use a solvent-based cleaner and a cloth to remove all grease and oil from the pipe surface. Wipe the entire surface of the pipe with the cloth to collect any remaining dust or rust particles, then allow the carbon steel to dry.
3. Open the zinc phosphate primer and stir it with a stirring rod until it reaches a uniform consistency. Use zinc phosphate primer because zinc forms a barrier, acting as an anode during electrochemical corrosion and deflecting pitting corrosion on carbon steel.
4. Apply the primer to the paintbrush and apply a thick coat to the carbon steel pipe. Allow the primer to dry according to the manufacturer's instructions.
5. Use a stirring stick to mix the polyurethane acrylic paint until the color is uniform. Use a paintbrush to apply a layer of paint to the pipe surface. Wipe off any paint that has entered the uninstalled carbon steel pipe end to prevent pipe contamination.
6. Allow the first coat of paint to dry according to the manufacturer's instructions. Generally, most acrylic paints are ready for the next coat after two hours. Finish the job by applying a final coat of polyurethane acrylic to the surface of the carbon steel pipe.

Due to industry requirements, API carbon seamless pipe requires attention not only to a smooth and bright surface but also to internal protection. Therefore, during the painting process, corresponding quality inspections should be carried out and the time should be properly controlled.