"PIPE ALLOY STEEL HT ASTM A335 GR P22 - SCH 80 . ASME B36.10 PLAIN ENDS (QUANTITIES UNIT : M)" is a set of technical specifications that describe alloy steel pipes. Let's analyze them one by one:

PIPE ALLOY STEEL HT:
"PIPE" means pipe, and "ALLOY STEEL" means alloy steel. Alloy steel is a steel that contains one or more alloying elements (such as chromium, molybdenum, tungsten, etc.) and has excellent properties such as high temperature resistance, corrosion resistance and strength.

"HT" usually refers to high temperature requirements, indicating that this pipe steel is suitable for high temperature environments.

ASTM A335 GR P22:
This is a description of the standard and grade of pipe materials.

ASTM A335 is a standard developed by the American Society for Testing and Materials (ASTM) for seamless alloy steel pipes, especially for high temperature and high pressure environments.
GR P22 is the specific material grade under this standard, where "P22" indicates the chemical composition and performance requirements of the pipe material. P22 alloy steel usually contains chromium (Cr) and molybdenum (Mo) elements, has good high temperature strength and corrosion resistance, and is suitable for high temperature environments.
SCH 80:
This refers to the wall thickness grade of the pipe, and "SCH" is the abbreviation of "Schedule".

SCH 80 means that the wall thickness of the pipe is relatively thick and can withstand high internal pressure. For SCH 80 pipes, its wall thickness is larger among pipes of the same diameter, which can increase its pressure bearing capacity and impact resistance.
ASME B36.10:
This is a standard developed by the American Society of Mechanical Engineers (ASME) that specifies the size, shape, tolerance, weight and other requirements of steel pipes. B36.10 specifically targets the outer diameter, wall thickness and other parameters of carbon steel and alloy steel seamless pipes and welded pipes to ensure the standardization and consistency of pipeline products.

PLAIN ENDS:
"Plain Ends" refers to pipes with no machining or connection ends, usually with smooth cut surfaces. Compared to pipes with threaded or flanged connections, plain end pipes are usually used in applications where welded connections are required.

QUANTITIES UNIT : M:
This indicates that the unit of measurement for the product is "meter", that is, the quantity of pipe is measured in meters, not pieces or other units.

The pipe described in this description is a high-temperature alloy steel pipe that meets the ASTM A335 GR P22 standard, with a wall thickness of SCH 80 and meets the ASME B36.10 size standard. The ends of the pipe are plain (no threads or flanges), the length is measured in meters, and it is suitable for piping systems in high temperature, pressure and corrosive environments.