Custom Precision Round Quartz Capillaries

Parameter	Factory Standard	Manufacturing Limit
OD	0.3–6 mm	—
ID (bore)	0.1–4 mm	—
Bore tolerance	±0.01 mm	±0.005 mm, confirmed per order
Concentricity	≤5% of wall	Tighter, confirmed per order
Roundness	≤1% of OD	—
Straightness	≤0.5 mm/m	—
Length	10–1,000 mm	—

Inquiry

Custom Precision Round Quartz Capillaries

Precision Round Capillaries quartz glass product image 2

Precision Round Capillaries quartz glass product image 5

Precision round quartz capillaries are used when circular bore size, outside fit and bore-to-OD position must be controlled in the same part. They suit analytical flow paths, sensor sleeves, alignment tubes and precision inserts that do not require a custom micro-bore, multiple channels or a heavy-wall section.

When to Use Precision Round Capillaries

Begin with the interface that determines performance: flow through the ID, clearance around an inserted element or fit within an external holder. Choose the bore and outside diameter for those interfaces, then set finished length and end condition. This avoids requesting the tightest tolerance on every dimension when only one controls the assembly.

ID Tolerance vs. Concentricity

An ID tolerance limits bore diameter; it does not establish where the bore lies inside the OD. A part can meet both ID and OD size limits yet place the inserted element off the holder axis. Where alignment depends on the outside surface, specify bore position against that datum and agree the measurement method. Add roundness or straightness only where sealing, rotation or usable length requires it.

Standard vs. Precision Bore Grades

Use the standard bore grade when the permitted clearance or flow variation can accommodate it. Request the precision-ID option when that variation directly affects the function, and review it with the selected ID, OD and finished length. The grades in the table below apply to ID; outside fit, centering and end-face tolerances must be called out separately on the drawing.

Round Capillary Control

OD, ID and Concentricity Define the Part

Controlled Feature	Reference Capability / Requirement
Bore ID	0.1–4 mm reference range
Outer Diameter	0.3–6 mm reference range
ID Tolerance	Standard ±0.01 mm / precision ±0.005 mm by order
OD Tolerance	Specified separately from ID according to holder fit
Concentricity	Bore axis controlled relative to the OD
Roundness	Applied to ID and/or OD only where sealing, rotation or alignment requires it
Straightness	Specified over finished length according to OD and function
Length	Up to 1,000 mm reference length; cut pieces by drawing
Ends	As-cut / ground square / chamfered / polished

Tolerance Grades

Do Not Apply Precision Tolerance to Every Feature

Grade	Reference ID Tolerance	Use When
Standard	±0.01 mm	General fluid paths, protective sleeves and non-critical fit
Precision	±0.005 mm by order	HPCE interfaces, sensor alignment and repeat nozzle liners
Drawing-Specific	Feature-by-feature review	OD fit, concentricity or end geometry is more critical than ID alone