This image shows the stop spring (core retainer) used in wireline coring drilling tools, also known as a core catcher or core spring. It is a key component in geological exploration and coring operations.

�� Product Information

· Material: Typically made of high-strength engineering plastic or nylon; metal versions are also available. The items in the image are black plastic models.

· Structure: Spherical or bowl-shaped, composed of multiple flexible spring fingers that converge inward to form a one-way valve-like structure.

· Quantity: 15 pieces are neatly arranged in the image, in 3 rows and 5 columns, which are likely spare parts produced in bulk.

��️ Main Functions

· Core Retention: During drilling, the core can enter the core barrel smoothly; however, when the drill string is pulled up, the spring fingers converge inward to grip the core tightly, preventing it from falling out and thus ensuring core recovery.

· Application Scenarios: Especially suitable for loose, fractured, or easily collapsed formations, such as coal seams and sand layers, where cores are prone to falling during lifting.

· Usage: It is usually installed inside the coring bit or at the bottom of the core barrel, working in conjunction with components like the core catcher seat.