How to Measure a
Pneumatic Conveying Bend

Determine DN, NPS, Outside Diameter and Wall

Begin by identifying the existing pipe or tube standard if it is available. Record the actual outside diameter in millimetres, wall thickness and accessible clear bore. Note whether the measured bore is reduced by a ceramic, basalt or hardfaced wear layer. If measurement is difficult, supply the original drawing or a pipe sample description.

Do not use the marking “DN100” or “4-inch” alone to determine a weld-end diameter: nominal descriptions vary across pipe and tube series.

Measure Bend Angle and Centerline Radius

For a continuously curved sweep, record the angle through which the centerline changes direction and the centerline radius (CLR). Specify whether your angle is flow deflection (for example, 90°) or an included angle from an older drawing. Include the tangent lengths before and after the arc; they materially affect the overall component dimensions.

For a segmented elbow, measure the overall angle and note the number of sections, individual joint angles and final face-to-face envelope if visible. A nominal CLR should be backed by the segment layout.

For Pocket Elbows, Measure Flange-Face and Envelope

A cast pocket elbow is not a constant-radius sweep. Measure the distances from each flange face to the crossing or reference axes, the overall height and width, the chamber projection, and available space for bolt access and removal. Record the arrow indicating flow direction and the intended mounting orientation.

Measure Flange Drilling and Facing

For each end, record flange outside diameter, bolt-circle diameter, number and size of holes, flange thickness and face profile. Note the declared EN/DIN or ANSI/ASME standard if marked. Check both ends, even if they look identical; previous modifications may have introduced mismatched interfaces.

Measure Straight Tangents and Adjacent Spools

When a flange or pipe end sits outside the main bend geometry, measure the additional straight lengths independently. Inspect supports, nearby instrumentation, insulation, neighboring spools and removal path. An elbow can match its nominal radius but still fail to fit the installed pipeline.

Prepare a Sketch and Photograph Set

Show inlet and outlet centers, product flow direction, connection faces and all measured dimensions on one annotated sketch. Take an overall installed photo and close-ups of both ends, part marking and any worn region. Include a scale reference, but use measurements—not inferred photo dimensions—for final fit.

Submit Replacement Measurements

Attach your measured sketch or current drawing with the desired materials, angle and wear concerns. We will identify any further measurements required before producing a model-specific quotation. Replacement assessment · Request quote.