Ball screw lead accuracy needs a named quantity and a defined travel interval. A statement about the whole useful travel, a 300 mm interval and one revolution describes different report fields. Keep the original designation with the quoted value.
For an aluminum feeding system, connect that component record to the actual offered assembly. Review complete-axis movement and finished cut parts using their own agreed requirements.
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Four ball screw lead accuracy terms to recognize
Steinmeyer’s lead-accuracy explanation separates these quantities:
| Quantity | Manufacturer’s described scope |
|---|---|
| ep | Averaged lead error over the entire useful travel. |
| vup | Whole-travel fluctuation, bounded by parallel lines around the averaged-error line. |
| v300p | Fluctuation for any 300 mm interval. |
| v2πp | Lead error within one revolution. |
Keep the reported designation, interval and units together. Ask the supplier to explain a different notation or abbreviated field.
Do not turn a row in this table into a dimensional acceptance limit. The applicable component specification and supplied report define the actual requirement.
Our ball screw vs lead screw guide covers the broader transmission comparison. Here the purchasing question is the scope of the lead-error quantity.
Keep the interval beside the quantity
Find the useful-travel definition used by the component record. Keep it separate from overall shaft length, complete-axis stroke and requested cut length.
If the report describes a local interval, preserve its scope in the comparison. A value without that interval can lose the information that tells the reviewer what was assessed.
Steinmeyer’s 300 mm discussion distinguishes cumulative and noncumulative descriptions. Clarify the actual requirement instead of multiplying a local value into an assumed whole-travel limit.
Ask the issuer how the stated field relates to the applicable full specification. Keep that explanation with the original component record.
A fictional quotation with an incomplete boundary
Imagine feed-axis inquiry A42. Offer A supplies only a micrometre value followed by “per 300 mm.” Offer B supplies a whole-travel field and an identified screw report. No actual tolerance or measured error is assumed here.
The buyer asks Offer A to name the quantity, its specification and the proposed component identity. The buyer asks Offer B to identify the useful travel and the meaning of its reported field.
The replies are placed beside the original wording. The comparison retains the local-interval and whole-travel headings instead of merging both into one column called “accuracy.”
Only after the scope is clear does the responsible reviewer assess each offer against the requested component requirement. More complete wording helps the review; it does not automatically prove a better component.
The example shows a document gap rather than a tested axis or customer event. Any actual limit must come from the approved requirement for the real project.
Identify the screw and its report
If a component report lists permitted and measured quantities in separate columns, retain those headings. Identify which field states the requirement and which records the finding. Keep the report reference beside any value transferred into the quotation comparison.
Keep the screw–nut assembly reference, relevant drawing revision and supplied report together. Ask which component the reported claim covers.
Retain the actual grade designation and its referenced specification. Ask the supplier to explain unfamiliar prefixes instead of assuming that a grade label has the same meaning in every document.
Record whether the submitted material is a general product description or the required evidence for the identified assembly. Keep those documents labelled by their actual purpose.
When a proposed component changes, review the identity and affected records before treating the replacement as equivalent. A matching nominal diameter and lead do not complete that review.
Connect the component evidence to the complete task
State the function of the proposed axis. Material advance, an adjustable stop and another positioning task need their own movement requirements.
Keep the defined movement sequence with the actual machine configuration. Request the complete-axis evidence required by the approved review plan.
Our ball screw preload guide addresses the separate clearance and stiffness question. Preserve those fields alongside the lead-accuracy record rather than using one statement to answer them all.
Then review the cut parts against their drawing. Define the finished-length reference, any required angle or surface features, and the agreed measurement scope.
A component report, an axis record and a finished-part report should remain recognizable in the handover package. Each is connected to the project by its own identified requirement.
If a supplier proposes one demonstration to address several requirements, ask it to show which observations answer each question. That keeps the evidence understandable without duplicating the same claim across every field.
Prepare a readable inquiry
Provide the actual profile drawing, required part lengths, quantities and movement pattern. Identify the machine function whose positioning scope matters to the project.
Ask the supplier to retain each proposed component designation, quoted quantity and reporting interval. Include the agreed axis and finished-part review requirements separately.
Send JiurunCut the cutting brief and request a configuration-specific explanation of any proposed screw-driven arrangement. Keep ball screw lead accuracy connected to its actual component record.
Common questions
Does “per 300 mm” identify the whole-travel limit?
Clarify the exact quantity and cumulative or noncumulative basis in the applicable specification. Preserve the original interval heading.
Does a screw report prove cut-length accuracy?
Use the agreed machine and finished-part review records for that requirement. Keep the screw evidence identified as component evidence.
Can I compare two grade labels by their numbers alone?
Retain the complete designation and referenced specification, then have the responsible reviewer assess the actual requirements.