China Suppliers Factory Accessories for Turning Tool Holder: Shim, Clamp, Clamping Screw, Center Screw, C Ring

A shim (also called a seat pad) is placed beneath the cutting insert in a turning tool holder to provide a stable, precise seating surface. It protects the tool holder pocket from damage during cutting and ensures the insert is held at the correct height and angle for accurate machining. Shims are available in various figures (A, B, C, D, E) and dimensions to match different insert sizes and holder configurations.

Selecting the correct clamp depends on the insert shape, the holder style, and the required clamping force. Key dimensions to match include the outer diameter (D), inner bore (d1), overall length (L), and height (H). For example, HL-series clamps are suited for standard lever-type holders, while WT and YW series are designed for specific holder geometries. Always refer to the specification table and cross-reference with your holder model to ensure compatibility.

A center screw (CTM / MX series) passes through the center hole of the cutting insert to secure it directly onto the shim and holder pocket — commonly used in screw-on type tool holders. A clamping screw (ML / WTCW series), on the other hand, is used to drive the clamp mechanism that holds the insert in place by applying downward pressure. Both types are critical for insert stability, but they serve different clamping systems.

Shims are generally made from hardened alloy steel or cemented carbide to resist wear and deformation under cutting loads. Clamps and screws are typically manufactured from high-strength alloy steel with surface treatments (such as black oxide or coating) to improve corrosion resistance and durability. The precise material grade ensures long service life even under high-temperature, high-pressure machining conditions.

Insert screws are used in screw-on type turning tool holders to lock the cutting insert securely into the pocket. To choose the right size, match the thread specification (d1), outer diameter (D), total length (L), and countersink angle (a) with your insert and holder requirements. For example, M2.5 screws are typically used with small inserts, while M4 or M5 screws are suited for medium to larger inserts. The angle (50°–60°) must correspond to the insert's countersunk hole geometry.

Yes, the shims, clamps, center screws, clamping screws, insert screws, and C rings listed here are designed to be compatible with standard ISO-style turning tool holders. The specification codes (such as MD, MC, MS, MT, HL, CTM, ML, etc.) follow common industry standards and are interchangeable with major tooling brands that use the same insert and holder systems. Always verify the dimensional specifications (d, h, L, D, F) against your existing tooling to confirm a proper fit before ordering.