TrueSpan^™ Stub Shaft

Polychem TrueSpan stub shafts are available in three configurable sizes for a variety of tank widths, loadings, and layouts. Stub shafts range from 12- to 25-inch sprocket distances from the wall. TrueSpan stub shafts are compatible with both standard and TrueSpan systems, offering onsite adjustment to accommodate many wall variations and sprocket centerline considerations. Each TrueSpan stub shaft can be equipped with two clamping collars to set sprocket centerline dimensions and an optional retainer plate to extend adjustability.

Benefits

Minimum six-inch sprocket adjustment per stub shaft

Easily field adjustable for installation flexibility

Reduces upfront engineering and lead times

Reduces custom components to simplify inventory and spares

Navigate Within Stub Shafts

Specifications

English Metric

Stub Shaft Size	Centerline Range From Wall (in)	Overall Length (in)	Journal Bearing Material	Set Collars	Optional Retainer Plate
Small	13 - 17	19.75	UHMW-PE	Cast Nylon-6 with 316 SS clamp	Polycarbonate
Medium	16 - 20	22.75	UHMW-PE	Cast Nylon-6 with 316 SS clamp	Polycarbonate
Large	18 - 24	26.75	UHMW-PE	Cast Nylon-6 with 316 SS clamp	-

Stub Shaft Size	Centerline Range From Wall (mm)	Overall Length (mm)	Journal Bearing Material	Set Collars	Optional Retainer Plate
Small	330.20 - 431.80	501.65	UHMW-PE	Cast Nylon-6 with 316 SS clamp	Polycarbonate
Medium	406.40 - 508	577.85	UHMW-PE	Cast Nylon-6 with 316 SS clamp	Polycarbonate
Large	457.20 - 609.60	679.45	UHMW-PE	Cast Nylon-6 with 316 SS clamp	-

A close-up view of industrial machinery with cogwheels, head shafts, and a chain, all shown in a blue-tinted color scheme.

System Animation

Learn how all the components in a Polychem TrueSpan system are assembled and installed.

Watch Video

Complementary Components

Retainer Plate

Bearings

Hardware

Cast Nylon-6 Set Collars

TrueSpan Adjustable Head Shafts

TrueSpan Adjustable Wall Brackets

Retainer Plate

Sprockets can be secured to the stub shaft with a single bolt using the polycarbonate retainer plate.

Bearings

The water-lubricated UHMW-PE tubular bearings spin on the spindle and are keyed to the outer end tubes to support the shaft. Oil-filled Nylon 6 bearings are available for specific cases where high temperatures and chemicals corrode UHMW-PE.

Hardware

Uses same legacy sprockets with greater field adjustment.

Cast Nylon-6 Set Collars

Collars secure telescoping tubes and sprockets on TrueSpan stub shafts and are fastened with a 316 SS band clamp.

TrueSpan Adjustable Head Shafts

Our FRP TrueSpan head shaft features an elongated common key end tube design that uses in-stock shaft components to minimize design and lead times, simplify inventory, and maximize adjustability.

TrueSpan™ Head Shaft