Gate valves are found in cross-country pipelines because?

Gate valves are specifically designed to allow line scrapers to pass through them, which is essential for maintaining cleanliness and functionality in cross-country pipelines. These valves open and close by raising or lowering a gate within the valve body, creating a straight path for the fluid, which is critical when using cleaning devices or scrapers that need to travel through the pipeline unobstructed.

This characteristic ensures that the flow of product through the pipeline can be maintained while enabling the use of internal cleaning mechanisms, which can help prevent the buildup of deposits or contaminants. This function is vital in long-distance pipelines where maintaining product integrity and cleanliness is essential for operational efficiency. Other options primarily focus on aspects like visibility or flow regulation that are not the primary reasons gate valves are utilized in these systems.