First, define what you are actually buying
Air-bearing precision motion projects often stall at the quotation stage for a simple reason: the buyer and the supplier are not quoting the same object. These are different deliverables, and they should not be mixed in one inquiry:
- Granite guideway components: lapped granite beams, base plates and mounting surfaces with the geometry and surface quality that air bearings need underneath them.
- Ceramic air bearings: the alumina bearing elements themselves, with their orifice or porous faces, supplied as components to your own motion design.
- Custom bases with air-bearing interfaces: granite or mineral structures with machined datums, bores and mounting interfaces prepared so that air-bearing components integrate into your assembly.
- Complete motion systems: motors, drives, controls, encoders and feedback integrated into a working stage — a system-level scope that must be agreed explicitly, component by component.
ZHHIMG supplies the first three categories as precision components and custom structures. Whether a specific project can include system-level integration is a scope question to be confirmed with our engineers per project, not an assumption to build into an RFQ. Clarifying this boundary up front is the single fastest way to get comparable quotations.
The parameter list to prepare before ordering
Each item below is something our engineers need to evaluate a granite air bearing guideway or related component requirement. Note that the values for any specific product come from its own drawing and data sheet — there is no universal air-bearing specification that covers all designs, so this list is about what you should specify, not about fixed numbers.
- Motion direction, travel and installation space: axis layout, required travel, and the envelope the assembly must fit, including cable and air line routing.
- Load and its location: payload mass, center of gravity position, and where loads act on the moving element. Load position decides bearing pre-load distribution and must be on the drawing, not described in words.
- Air supply and environment: available supply pressure and quality (filtration and dew point per your facility), cleanliness class of the working environment, and temperature range at the installation site.
- Guideway geometry and surface requirements: straightness over travel, flatness of reference surfaces, parallelism between paired surfaces, and the acceptance standard each requirement references.
- Assembly interfaces: mounting datums, insert and bore positions, and how the guideway components mate with drives, encoders and limit systems — including who supplies the mating parts.
- Acceptance items and methods: which features are acceptance-critical, how they will be measured, and what information you will provide (assembly drawings, load data, air supply data) for the review.
Why load position matters more than load weight
Among all the parameters above, the one most often missing from first inquiries is the center of gravity of the moving assembly. An air bearing carries load through a film whose pressure distribution is designed around where the load actually presses. The same mass applied at a different height or offset changes the moment on the bearings and therefore the design of the whole guideway interface. If you cannot yet state the center of gravity, say so explicitly and expect the supplier to assume a conservative case or to ask.
A fillable inquiry form
Copy this into your RFQ and fill in what you know; mark “TBD” openly rather than guessing:
- Axis and travel: number of axes, travel per axis, direction of motion
- Envelope: maximum installation space and mounting orientation
- Payload: mass, center of gravity, load application points
- Air supply: available pressure, filtration, dew point
- Environment: cleanliness class, temperature range, vibration sources nearby
- Geometry requirements: straightness / flatness / parallelism per surface, with acceptance standard
- Interfaces: datum surfaces, insert and bore schedule, mating components (drive, encoder, cable chain)
- Acceptance: critical features, measurement methods, documents required
The photo below shows a family of precision granite components and rail interfaces of the kind that serve as the structural foundation under air-bearing stages — the parts of the system whose geometry you are actually specifying with this list.
What a technical review looks like on our side
When an inquiry arrives with the parameters above, the review on our side covers: feasibility of the requested geometry in granite or ceramic, the interface datums and their tolerances, the alignment between your load data and the bearing arrangement in your assembly drawing, and the inspection plan for the acceptance-critical features. The output is a quotation with the assumptions stated — because a quotation whose assumptions are invisible is the most expensive kind.
Send your parameters for review
Share your load, travel, air-supply conditions, and assembly drawing for a technical review. ZHHIMG engineers will check the interface and geometry requirements against what the ceramic air bearing and granite guideway components can deliver, confirm the supply scope, and return a quotation with its assumptions in writing — contact ZHHIMG to start.
Post time: Oct-12-2026