An adjustable coupling, also known as a pipeline compensation coupling, is a new product for connecting pumps, valves, pipelines, and other equipment to pipelines. It is assembled by bolts to form an integrated unit with a certain displacement capacity. It is categorized into AY type pressure cover adjustable coupling, AF type flange loose fit adjustable coupling, BF type single flange limiting adjustable coupling, B2F type double flange limiting adjustable coupling, BY type pressure cover loose fit limiting adjustable coupling, CF single flange force transmission coupling, and C2F double flange force transmission coupling, etc.