Automation Ball Screw RFQ: How to State Application Parameters

Do not send a model number alone

Ball screws in automation equipment may drive positioning, transfer, inspection, dispensing, pressing, or adjustment mechanisms. A single model number cannot show whether the screw suits the real application, so the RFQ should describe load, speed, travel and mounting method together.

A model number only states diameter and lead, while the same specification can last several times longer in one duty than another — which is why application parameters are worth more than the model.

Describe load and speed separately

Load should state horizontal or vertical direction, workpiece weight, slide weight, acceleration and whether shock is present. Speed should state maximum, normal working speed and cycle time, not one theoretical maximum.

Thrust converts directly: F = mass × acceleration. A 30 kg slide plus workpiece at 5 m/s² needs about 150 N of accelerating thrust; if the axis is vertical, add 30 × 9.81 ≈ 294 N to overcome gravity, giving roughly 444 N before a safety factor. Once that is calculated, the usable range of lead and diameter is already set.

Travel and mounting method drive diameter and lead

Travel, support span, fixed side and support side structures affect critical speed, rigidity and end machining. Mounting can be horizontal, vertical, inclined, twin-rail supported, single-end driven or double-end supported, and all of it belongs in the RFQ.

Long travel is limited mainly by rpm: critical speed falls with the square of the support span, so "run fast with a large lead" may simply not be available once the span grows.

Accuracy and life expectation set the cost boundary

Do not write "accuracy as high as possible". State positioning accuracy, repeatability, backlash or preload. Life expectation can be expressed as daily working hours, cycles, annual output or maintenance interval, which is what sizes the screw and the nut arrangement. For the grade choice, see C7 vs C5 ball screw selection.

Life is most useful as cycles or running distance: "8 hours a day, 20 cycles a minute, 5 years" works out to roughly 120 million cycles, and that figure decides whether a higher dynamic load rating or a better lubrication plan is needed.

Quantity and project stage change how a quote is built

Samples, pilot runs and batch purchases differ in quantity, lead time and packing. The RFQ should state the first batch, monthly volumes, whether spares are needed, and whether an inspection report, labels and shipment photos are required.

How to fill each parameter

Parameter	How to write it	What it drives
Load	Direction + slide/workpiece weight + acceleration + shock	Diameter, lead, thrust margin
Speed	Maximum + normal + cycle time	Lead, motor rpm, critical speed
Travel	Working travel + support span	Critical speed, rigidity, end machining
Mounting	Horizontal/vertical/inclined, single or double end	Brake need, support structure
Accuracy	Positioning, repeatability, backlash or preload	Grade, preload, inspection scope
Life expectation	Cycles or running distance	Dynamic load rating, lubrication interval
Quantity and stage	Sample/pilot/batch + monthly forecast	Quoting basis, scheduling, packing

Application decision table

Automation condition	Parameter to send	Why it affects selection
High cycle equipment	Cycle time, speed, acceleration, duty	Affects lead, lubrication, and life expectation.
Heavy load or vertical motion	Load direction, safety factor, brake need	Affects diameter, lead, and thrust margin.
Compact machine layout	Mounting method, support unit, motor connection	Affects end machining and assembly fit.
Precision positioning	Accuracy, repeatability, backlash	Affects grade, preload, and inspection scope.

RFQ checklist

Automation equipment type, axis, working stroke, mounting method, and space limits.
Load, speed, travel, acceleration, cycle time, and life expectation.
Required accuracy, repeatability, backlash, preload, and inspection report needs.
Support unit, motor connection, coupling, nut orientation, and end machining drawing.
Quantity, trial sample plan, batch forecast, packing, destination, and delivery target.

Send us the automation application data

Send weimute the application parameters and any machine layout drawing. Our manufacturing and sales team will separate selection questions from manufacturing questions, then quote a practical ball screw route for samples or batch quantity.

FAQ

Can I quote automation equipment by model only? It is risky. Load, speed, travel, mounting method, accuracy, and life expectation decide whether the model is suitable. See C7 vs C5 ball screw selection for how accuracy grade affects cost.

What if the design is still changing? Send target ranges and mark uncertain points so weimute can give selection guidance before final drawing confirmation.

How should life expectation be written? In cycles or running distance, for example "8 hours a day, 20 cycles a minute, 5 years". "Durable" tells the supplier nothing, and forces a conservative quotation.

Next step

Turn this guide into an RFQ

When the specification direction is clear, send the details below together with quantity, lead time, and packing requirements.

Include these details

Model, diameter, lead, accuracy grade, or target application.
Load, speed, travel, mounting method, and matching rail or support-unit needs.
Quantity, lead time, packing, and whether inspection records or shipment photos are needed.

Send automation application parameters View applications