CNC Machined Components, Sleeves & Pins Suppliers

Sleeves, Pins and Machined Components Produced In-House

As a Custom CNC Machined Components, Sleeves & Pins Suppliers, Exporter, we match product configuration to the application, operating limits, interfaces and acceptance criteria defined for each project.

Zhejiangxinye Automobile Technology Co., Ltd. has manufactured automotive fasteners and stamping parts since 1995, and our machined product family carries that production base into sleeves, couplers, locating pins, shafts and turned components. Raw material analysis, forming, machining, threading, heat treatment, surface finishing and final inspection all run inside our own plant, which operates under IATF 16949-2016.

These are the parts that sit between the fastener and the structure: a suspension sleeve that sets clamp length and carries bolt preload, a stepped locating pin that positions a seat frame, a bushing that holds concentricity in a moving joint. Our CNC Machined Components, Sleeves & Pins range covers a series of proven geometries, and we machine to drawing where an assembly needs a specific step, flange, bore or thread form.

• Thirty years of automotive component manufacturing, with more than 500 product varieties across fasteners, stampings and machined parts.
• Tolerance bands controlled from 0.06 mm to 0.30 mm according to feature and application.
• Trivalent zinc plating tested to 480 h salt spray; Zn-Ni alloy plating from 480 h to 720 h.
• Temperature-resistant grades available at 300 °C, 550 °C and 650–700 °C for exhaust-adjacent and engine-periphery duty.

Our Machined Component Range

Where These Parts Fit in the Vehicle

Chassis and suspension joints, seat structures, interior trim attachment and body hardware all use the same component logic: a spacer sleeve establishes clamp length so the bolt does not crush the bracket, a pin fixes location while a separate fastener carries the load, and a bushing controls radial clearance. Our machined parts are configured against that function, not only against a shape.

The three sub-families are supplied as Sleeve Parts & Couplers, Pins & Shafts and CNC Precision Machined Components, each with its own drawing and inspection route.

Materials, Finishing and Environmental Load

Carbon steel is the working base for most of the range, with the grade selected against strength class, wall thickness and thread depth. Coating and heat treatment follow the location on the vehicle: a sleeve inside a cabin structure has different exposure from one at the lower suspension arm or near the exhaust.

Critical Specifications We Hold on Machined Parts

• Dimensional control: tolerance bands from 0.06 mm to 0.30 mm, assigned per feature according to fit and function.
• Thread geometry: nominal diameter, pitch, thread depth and run-out, checked against the mating bolt and the required assembly torque.
• Step and flange accuracy: shoulder position, flange diameter and thickness determine clamp length and must match the stack-up in the joint.
• Concentricity: bore-to-OD alignment on bushings and sleeves, so the part locates without forcing the joint off centre.
• Surface and hardness: coating thickness, freedom from burrs at thread entry, and hardness after heat treatment verified on test pieces.

How We Configure a Part for Your Assembly

Configuration starts from the joint, not from the shape. We review the drawing or sample, identify which dimensions carry the function, and then set the process route and the gauging method that will hold them in series.

1. Drawing, 3D model or physical sample review, including the mating bolt, bore or bracket.
2. Material grade, strength class and heat treatment matched to the load path.
3. Process route fixed: forming or bar stock, turning of steps and flanges, drilling, threading, heat treatment when required, then finishing.
4. Inspection plan defined for the critical features, with gauge or instrument selection agreed before the first batch.
5. Sample evaluation, then series release on the approved setting.

Quality Control and Acceptance

Our quality system is certified to IATF 16949-2016, and the plant also holds Work Safety Standardization and Environmental Management System certification. Control runs from incoming raw material analysis through production processing to finished product mechanical performance testing, with documented work instructions for special and critical processes.

Hardness testing, dimensional inspection and thread gauging are performed at defined stages rather than at final inspection alone, so a drifting step diameter or thread depth is caught before the batch is complete. Inspection records are retained per lot for traceability against the delivered quantity.

Information We Use to Configure Your Solution

The faster the joint conditions are clear, the faster the proposal is technically correct. We work from the following inputs when preparing a configuration and quotation:

• Part drawing or 3D model, with critical dimensions and the tolerance that must be held.
• Material grade, strength class and any heat treatment requirement.
• Coating type, coating thickness and salt-spray expectation.
• Mating components: bolt thread, bore diameter, bracket thickness and clamp length.
• Operating conditions: temperature at the location, exposure to spray or road salt, vibration.
• Assembly method, tooling access and any automation feeding requirement.
• Annual volume, batch size and delivery schedule pattern.
• Inspection documentation expectation and packaging format per carton or returnable bin.

Documentation, Packing and Reorder Consistency

Each order is shipped against the approved drawing revision, and the coating, heat treatment and inspection route stay fixed between repeat batches so a reorder assembles the same way as the first delivery. Packing format, labelling content and the inspection documents supplied with the shipment are agreed with the purchase order, including part-number marking where the assembly line requires it.

Because sleeves, pins and machined bushings are produced alongside our flange nut, weld nut and stamping programmes, a single purchase order can cover the machined part and the mating fastener from the same plant.

Frequently Asked Questions

Can you machine a sleeve or pin to our drawing instead of a catalogue shape?

Yes. Most of our machined output is built to customer drawings, with the step, flange, bore and thread defined by the mating assembly. Send the drawing or a 3D model with the critical features marked, and we will confirm the process route and the dimensions we will inspect.

What material and finish do you recommend for suspension mounting sleeves?

Carbon steel with a black finish is common for sleeves that sit inside a clamped joint, while lower-arm and underbody positions usually call for Zn-Ni alloy plating at 480 h to 720 h salt spray. The choice follows the exposure at the mounting point and the strength class the joint requires.

How do you control thread fit and concentricity on machined bushings?

Thread nominal size, pitch, depth and run-out are gauged at defined stages, and bore-to-OD concentricity is set by machining the bore and outside diameter in the same setup where the geometry allows. Tolerance bands are assigned per feature within our 0.06 mm to 0.30 mm control range.

Do you supply the mating nuts and fasteners together with the sleeves and pins?

We do. Flange nuts, weld nuts, self-locking nuts, clinch nuts and non-standard nuts are produced in the same plant, so a sleeve or pin and its mating fastener can be quoted and delivered as one package with matched thread and coating.

What information is needed for a quotation on machined components?

A drawing with tolerances, material and coating requirements, the mating bore or bolt, annual volume and batch size are enough to start. Where the part already exists as a sample, we measure it and confirm the critical dimensions with you before quoting.

Is the machining and finishing carried out in your own factory?

Production is completed in-house from raw material to finished goods, including forming, machining, threading, heat treatment, surface finishing and mechanical performance testing. That is also why our machined parts and fastener programmes share one quality system under IATF 16949-2016.