What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
The rivet provided by Yueluo Creation includes a mandrel and a coaxial matching nail sleeve outside the mandrel; the mandrel includes a head, a central rod and a tail, and a position close to the head is provided with an inner A concave section of the lock ring area, a position close to the tail is provided with a section of lock area that inclines and shrinks inward along the direction of the head to the tail; the lock ring area of the core rod is gap-fitted and fixed with a lock ring , a part of the lock ring is located inside the sleeve head of the nail sleeve, and the part of the lock ring located outside the sleeve head of the nail sleeve can be interference fit with the nail sleeve; the nail sleeve The sleeve is provided with a through hole for the core rod to penetrate into, the inner wall of the nail sleeve forming the through hole is provided with a protruding structure, and one end of the protruding structure is close to the sleeve head of the nail sleeve The end of the core rod is close to or adjacent to the end of the tail of the core rod.
Guangdong Yueluo Hardware Industry Co., Ltd. discloses an eccentric special-shaped rivet, which has a simple structure and is inexpensive to manufacture. The eccentric shaped rivet includes a cylindrical head and an eccentric polished rod. The diameter of the cylindrical head is larger than that of the eccentric polished rod. The eccentric polished rod is arranged at the lower end of the cylindrical head, and the axis of the eccentric polished rod is not the same as the axis of the cylindrical head. on the same straight line. The eccentric special-shaped rivet has low manufacturing cost and is easy to realize automatic assembly.
This clearance determines how much the bone fragment fixed by means of the locking screw in the corresponding locking hole can move relative to the nail and thus also relative to other bone fragments fixed by the same nail due to the rigidity of the nail. Together with the flexibility of the material and the overall device this can build up to a size that prevents or decisively delays effective healing. In order to ensure the applicability of the locking device to the surgeon, this gap, although unavoidable, is clinically undesirable in some indications (eg in the case of metaphyseal fragments). Even a screw with a full cross-section, which can have an internal thread in the locking hole, is not gapless. This internal thread only prevents possible axial movement of the screw on the locking screw.
1) Scope This standard specifies the lock nut (referred to as nut), the size of the locking device, technical requirements, acceptance rules and measurement methods. This standard applies to the design, production, inspection and user acceptance of nuts and locking devices for tapered bushings. 2) Terminology The terms used in this standard conform to the provisions of GB/T 6930. This standard specifies the marking system, index, test method and marking of the mechanical and working performance of the effective torque section steel hexagonal lock nut. This standard is applicable to coarse thread 6H class nuts made of carbon steel or alloy steel, the width across the sides conforming to the provisions of GB 3104, the nominal height is ≥ 0.8D, and the guaranteed load and effective torque need to be specified, and the thread diameter is 3 ~ 39mm. Except for the effective torque part, the thread size and tolerance are specified in GB 193, GB 196 and GB 197. The working temperature range of the nut should be in accordance with: All-metal nut without electroplating treatment: -50℃～+300℃. All-metal nuts with electroplating treatment: -50℃～+230℃; nuts embedded with non-metallic elements: -50℃～+120℃. This standard does not apply to nuts with special performance requirements (such as weldability and corrosion resistance). For stainless steel and non-ferrous metals with fine pitch lock nuts or thin nuts made of carbon steel or alloy steel, the performance indicators and test methods of effective torque specified in this standard may be adopted by mutual agreement.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
