The smallest SP wedge-belt section — built for compact, high-speed drives where every millimetre of frame width counts.

The SPZ belt is a wrapped metric V-belt with a 9.7 mm top width, an 8 mm section height and a 40° wedge angle. It is the smallest section in the SP series, and that size is the whole point: the 40° wedge sinks deeper into the sheave groove and develops more grip per millimetre of belt width than a classical Z-section belt. A drive that would need a wider classical belt can often be done with an SPZ — smaller sheave, lighter shaft load, less bearing wear.

Because the SPZ is the smallest SP section, it is the one called for when the frame is already tight and the load is moderate but continuous. That combination — a compact footprint with steady torque — is where the 40° wedge earns its keep, and it is why the section shows up across printing presses, textile machines, packaging lines, pumps and ventilation systems.

Our SPZ belts are moulded rather than cut, so every belt of the same specification leaves production with an identical datum length. In a matched multi-belt drive that means every belt carries the same share of load from the first hour. No one belt runs tight and takes the punishment, no flank wears out early, and no unexpected break stops production. Because different production batches are moulded to the same length tolerance, a replacement ordered months later drops straight into the same drive without re-engineering the frame.

Every belt is manufactured to ISO 4184, the international standard covering dimensional tolerances and performance requirements for V-belts. When you specify our SPZ belt, you are ordering a part that seats correctly in any ISO 4184-compliant SPZ sheave and runs to a known length tolerance.

Complete Technical Specifications

Verified under ISO 4184 test conditions. Supplied in matched datum lengths for multi-belt drives.

Materials & Construction

Three layers, each doing one job properly. Built on chloroprene rubber for genuine resistance to oil, heat, ozone and static.

Why Choose Our SPZ Wrapped V-Belt

Every claim below is measurable on the drive, not just on a spec sheet.

Industries & Equipment Served

The SPZ is specified wherever the frame is tight, the load is steady, and a smooth-running drive protects product quality.

Printing

Web and sheet-fed presses, folding machines and auxiliary equipment. Low vibration and a compact drive are non-negotiable here — belt chatter shows up as registration drift on the sheet. SPZ and SPA are the sections most often specified.

Textiles

Spinning, weaving and finishing-line auxiliaries. Continuous high-speed running makes belt life a direct maintenance cost, and smooth, stable running protects fabric quality.

HVAC & Building Services

Air handling units, ventilation fans, industrial refrigeration and commercial air conditioning. Quiet, efficient running and a long, maintenance-free service interval.

Agricultural Machinery

Seed drills, rotary tillers, mowers, rice mills, micro-tillers, fertiliser spreaders, paddy de-huskers, grain grading screens, cleaning screens, ditch openers and pruning machines.

Petrochemical & Plastics

Dryers, industrial refrigeration, dehumidifiers, mixers, pulverizers, vacuum formers, blow moulders, extruders, forming machines and pelletisers.

Steel & Metallurgy

Auxiliary equipment across drilling machines, sawing machines, plate shears, forming machines, conveyors, separators and feeding systems. Where the main drive calls for a larger belt, the auxiliaries are often SPZ.

Food & Beverage — Including Ice-Cream and Dairy Lines

SPZ is the specified section for household ice-cream machines, washing machines, commercial freezers and central air conditioning. Oil and washdown resistance matter, and the compact profile fits equipment built to a tight envelope.

Auxiliary Equipment Across All Sectors

Fans, electric motors, gear reducers, mixers, air compressors, pumps and pulverizers. If a machine needs to turn reliably in a tight frame, the SPZ belt is on the bill of materials.

Length Marking & Matched Sets

An SPZ belt code reads as SPZ followed by the datum length in millimetres. The number is the datum length; the outside circumference is longer by the standard profile offset and is listed in the downloadable chart below.

The SP range uses metric pitch-length marking, which keeps the procurement side simple: specify the length you need in millimetres, order the matching code, and the belt arrives at that length. Because the belts are moulded to a consistent datum length, every belt in a multi-belt set carries the same share of load. A common failure pattern is one new belt paired with several worn belts: the new belt runs tight, takes almost all the tension and fails in days. Replacing the full set is always the lower-cost choice over the life of the drive.

If you are unsure of the correct length, send us the centre distance, both sheave diameters and the service factor you want to apply. Our engineering team will return a recommended belt code, normally within one working day. MOQ: 100 pcs per size  |  Delivery: 15-20 days

Installation & Maintenance

Correct Installation Procedure

1. Loosen the driven-unit mounting bolts and reduce the centre distance before fitting the belt. Never lever a belt over a sheave rim — the forced bend will break tension cords at one point along the belt.
2. Seat the belt in the grooves, then increase the centre distance gradually to apply tension.
3. Tension to the specified value with a proper tension gauge. Too tight overloads the bearings; too loose causes slip, heat and rapid wear.
4. Run the drive 15–30 minutes under light load so the belt beds into the grooves, then re-check and adjust tension once.
5. Check sheave alignment with a straightedge. Misalignment wears one belt sidewall quickly and shortens belt life.

Maintenance Guidelines

• Inspect belts every 500 operating hours for glazing, cracking or exposed cords.
• Keep sheaves clean and free of oil, grease and embedded debris.
• Replace all belts in a matched set together — never replace one belt alone.
• Store spares in a cool, dry place away from direct sunlight and ozone sources such as electric motors.

Troubleshooting Guide

The belt cannot be tensioned

Possible causes: the centre-distance adjustment range is too small; the belt has stretched beyond recovery or the drive frame is undersized and overloaded; the belt length is wrong.
Remedies: re-design the drive with a larger adjustment range; re-calculate the drive data and resize the drive; select the correct SPZ length.

The belt wears out too quickly

Possible causes: the belt has exceeded its service life and the compound has aged; the drive imposes excessive tension; poor installation causes misalignment, uneven wear or vibration.
Remedies: replace on a fixed schedule, correct the drive design, and align and seat the belt properly at installation.

The belt breaks after a short time

Possible causes: it was pried onto the sheave and cords were damaged; a foreign object entered the drive and snapped it; the driven system seized; severe shock loading or a load applied too suddenly.
Remedies: loosen the mounting bolts and reduce centre distance to fit the belt with no forced leverage; fit a guard to keep debris out; stop and clear the fault before restarting; re-design for the actual shock load and ramp loads up gradually.

Black powder is coming off the belt

Cause: on a new installation the sheave surface finish is too rough, so the belt rubs off fine black rubber dust.
Remedy: improve the sheave surface finish.

The belt slips

Possible causes: insufficient tension, worn or contaminated sheave grooves, or a drive ratio that no longer matches the requirement.
Remedies: adjust tension to the specified value with a tension gauge; inspect and replace worn or contaminated grooves; correct or replace the drive so the ratio matches.