DZ40, DZ50, and R780 geological pipes are specialized pipes used for geological exploration, each with its specific specifications and uses. The following is a detailed analysis of these three types of geological pipes:
DZ40 geological pipe:
Specification: The article mentions that one specification of DZ40 petroleum geological pipe is 1084.5, with an outer diameter of 108 millimeters and a wall thickness of 4.5 millimeters. However, the specification 1686 was not directly mentioned, but it can be inferred that the DZ40 geological pipe may have multiple different specifications.
Usage: DZ40 petroleum geological pipe is mainly used for drilling reinforcement engineering, especially for drilling rock layers to obtain geological data and samples.
Material and characteristics: DZ40 geological pipes are usually made of high-quality steel and undergo strict production processes to ensure their strength, corrosion resistance, and wear resistance.
DZ50 geological pipe:
Specification: The article clearly mentions that one specification of DZ50 seamless steel pipe for geological drilling is 108 * 8, with an outer diameter of 108 millimeters and a wall thickness of 8 millimeters. Similarly, this is only one specification, and DZ50 geological pipes may have multiple specifications.
Usage: DZ50 seamless steel pipe for geological drilling is suitable for various geological drilling scenarios.
Material and characteristics: The seamless steel pipe for DZ50 geological drilling is mainly made of high-quality alloy steel materials such as DZ50 (45Mn2), which has good strength and toughness.
R780 geological pipe:
Specification: The article mentions a specification of R780 geological pipe, which is 60.3 * 7.1, with an outer diameter of 60.3 millimeters and a wall thickness of 7.1 millimeters. Similarly, this is only one specification of the 
R780 geological tube.
Usage: The R780 geological tube is mainly used for geological exploration and mineral resource development.
Material and characteristics: Although the article does not directly mention the material and characteristics of R780 geological pipes, it can be inferred that they are also made of high-quality steel to meet the high strength, corrosion resistance, and wear resistance requirements of geological exploration for pipes.
Summary: DZ40, DZ50, and R780 geological pipes are important pipes used for geological exploration, each with different specifications, uses, and material characteristics. When selecting geological pipes, it is necessary to choose appropriate specifications and materials based on specific drilling requirements and geological conditions.