Extra-Long Straightness Bolt Manufacturer｜Micron-level straightness, one-piece cold heading
Extra-long straightness bolts for motors: the extra-long shank is cold-headed in one piece with micron-level straightness control throughout, preventing bending and jamming of slender bolts during assembly. Developed for large length-to-diameter ratio motor shaft fixation, precision power transmission and fixture locating; dimensions made to drawing.
Why Choose YF Zhichengjia Extra-Long Straightness Bolts
Extra-long one-piece forming
Shank machined in one piece, no jointed steps
Micron-level straightness
Full-length straightening and inspection: smooth assembly without jamming
High-strength materials
Quenched-and-tempered alloy steel: stable tensile and fatigue performance
Consistent accuracy
Good batch consistency, automation-friendly
Test reports
Straightness and dimensional inspection reports with delivery
Made to drawing
Shank diameter, length, head and thread made to drawing
Extra-Long Straightness Bolt Series
Extra-Long Straightness Bolts (1 model)
Wire Thread Insert
This extra-long straightness bolt for motors offers extremely high straightness accuracy, ensuring stable and reliable motor assembly, reducing vibration and wear, and improving motor efficiency and service life
Extra-Long Straightness Bolt Selection Guide
1. Assess by length-to-diameter ratio
The larger the length-to-diameter ratio, the harder straightness is to control. Provide shank diameter × length and straightness requirements; we will assess feasibility.
2. Straightness callout
Specify the full-length straightness tolerance and measurement datum on the drawing to avoid acceptance disputes.
3. Material and strength
Select the quenched-and-tempered alloy steel grade by load; weight consistency must be controlled in applications with high dynamic-balancing requirements.
4. Assembly advice
Use guiding fixtures when assembling slender bolts; avoid hammering them in, which causes bending.
5. Customization process
Drawing submission → process evaluation → sample prototyping → full-inspection report → volume supply.
Typical Applications
Servo motors
Extra-long shaft-extension fixation, high-precision transmission
Spindle motors
Precision connection of high-speed spindle components
Linear motors
Precision assembly of linear motor stators and rotors
Precision lead screws
Long-bolt connections for lead screws and couplings
Automation Equipment
High-precision fixtures and locating mechanisms
Testing instruments
Instrument structures demanding high straightness
Extra-Long Straightness Bolts FAQ
Q1How straight can you make it?
Micron-level straightness can normally be guaranteed (depending on length-to-diameter ratio and shank diameter). Please state the tolerance on your drawing; we will confirm a committed value after process evaluation.
Q2Why do extra-long bolts bend easily?
Machining and heat-treatment residual stresses bend slender shanks; we control this through cold heading, multiple straightening passes and stress-relief treatment, with 100% inspection throughout.
Q3What is the MOQ?
Non-standard custom products support sample prototyping; volume MOQ is assessed by specification. Inquiries welcome.
Q4What's the approximate lead time?
Samples are usually ready within 1-2 weeks; lead time for volume orders is assessed by quantity and process. Urgent needs can be scheduled by negotiation.
Q5Which test reports do you provide?
Dimensional 100% inspection and straightness test reports provided; material certificates and hardness reports on request.
Q6Can you produce other non-standard bolts for motors?
Yes. All kinds of non-standard motor bolts, stepped bolts and special-head bolts can be custom made to drawing.
Need the full catalog or drawing-based custom extra-long straightness bolts?
Send specifications, drawings or application details for selection advice, test reports and a fast quote — direct to our sales lead.
