Precision Medical Screw Machining

Sanluo Precision is a professional manufacturer and supplier of precision medical screw machining in China. It is also a well-known medical screw and orthopedic implant fastener manufacturer in the current Chinese industry, providing professional customization services for customers. The company mainly produces medical fasteners such as bone screws, bone plate screws, spinal screw rod systems, and joint replacement screws. It offers high-standard customized precision medical screw machining for orthopedic medical device enterprises, supporting the customization of complex and difficult parts.

Send Inquiry

Product Description

Precision machining of threads

Sanluo Precision adopts the spiral wind milling and spiral pressing forming processes in precision medical screw machining. The spiral milling of titanium alloy and stainless steel screws ensures a pitch accuracy of ±0.01mm, a tooth profile angle accuracy of ±15', and a surface roughness Ra value range of 0.8-1.6μm. The spiral pressing forming process can increase the screw strength by 30%, forming a cold work hardened layer on the surface and increasing the fatigue strength by 40%.

Workstation Accuracy Table

dimensional accuracy	OD	ID	T（C）	DP	R
unit:±/mm	0.002	0.003	0.005	0.005	0.01
Geometric accuracy	roundness	coaxiality	straightness	cylindricity	profile tolerance
unit:±/mm	0.001	0.004	0.002	0.003	0.002
production capacity	1~999999 pcs	1~999999 pcs	1~999999 pcs	1~999999 pcs	1~999999 pcs
production cycle	3-20 days	3-20 days	3-20 days	3-20 days	3-20 days

Materials and Heat Treatment

As a professional manufacturer of precision medical screw machining, the medical titanium alloy used by Sanluo Precision Factory is Ti-6Al-4V ELI (ASTM F136), and the medical stainless steel is 316L (ASTM F138). The titanium alloy is annealed (at 700°C to 800°C) to eliminate processing stress, with a tensile strength greater than 860 MPa and an elongation of not less than 10%. The stainless steel undergoes solid solution treatment (at 1050°C), resulting in a single-phase austenitic structure, with a tensile strength of not less than 490 MPa and a yield strength of not less than 190 MPa. The sand material with 60 to 80 mesh is used for sandblasting to form a rough surface (Ra 3-5 μm), which is conducive to bone integration.

Precision Medical Screw Machining

Packaging and Sterilization

After the precision medical screw machining is completed, Sanluo Precision Company performs packaging and sterilization. The screws are packaged in medical-grade blister boxes made of PETG transparent plastic, which is convenient for preoperative observation. An inner layer of EPE foam or blister tray is used to prevent damage caused by collisions during transportation. The outer packaging is made of Tyvek medical dialysis paper and plastic composite bags, which can meet the requirements of EO sterilization and radiation sterilization. EO sterilization and gamma ray sterilization, with a sterile assurance level of SAL 10⁻⁶. After sterilization, EO residual detection is conducted on the residues (EO residual ≤ 10 ppm) to ensure the safety of the implants.

Technical Specifications

Parameter Categories	Parameter Details
Equipment Model	INDEX TNL32 Artistic-style Turning and Milling Combined Center
Core Positioning	High-precision and high-complexity processing of medical screws
Spindle Speed	Maximum 8,000 rpm
Spindle Inner Diameter	32 mm
Maximum Z-axis Travel	305 mm
Multi-tasking Capability	Up to 3 cutting tools can be processed simultaneously.
Machine Structure	The thermally symmetrical machine structure helps maintain high precision over a long period.
Core Advantages	It can be easily switched between the sliding spindle box and the fixed spindle box operation modes, with high flexibility.
Typical Applications	High-end precision medical screw machining

Parameter Categories	Parameter Details
Device Model	Tsugami S205A Precision Machine (with optional high-frequency milling)
Core Positioning	Specializes in precision machining of small shaft parts such as stainless steel, titanium alloy bone screws, dental pins, etc. for the medical industry
High-frequency Milling Accessories	Optional installation of Japanese NAKANISHI BM-320F high-frequency milling machine with a maximum rotational speed of 80,000 rpm and a jump accuracy of 1μm
High-frequency Milling Dimensions	Outer diameter 20mm, length 87mm, can be directly installed in the tool holder hole of Tsugami S205A for use
Processing Function	Used for high-precision milling of "rose" (such as internal hexagon, TORX®) on the end face of titanium alloy bone screws, requiring no burrs
Core Advantages	The Tsugami S205A machine itself is suitable for continuous processing of slender shaft parts; with the addition of the high-frequency milling machine, all processes can be completed on the same machine to ensure consistency in accuracy
Typical Applications	Titanium alloy bone screws, bone screws, dental pins, etc.