V-belt XPZ 987 - 10x8 MM - PIX X'tra ®

V-belt XPZ 987 - 10x8 MM - PIX X'tra ® for industrial belt drives with XPZ profile

V-belt XPZ 987 - 10x8 MM - PIX X'tra ® is a raw edged and Cogged V-belts from the PIX X'tra® series. It is intended for belt drives where the profile, length and pulley groove must match exactly to ensure stable operation. This variant has profile XPZ, goal 10x8MM, effective length Ld 987 mm, inside length 950 mm and external length 1000 mm.

XPZ is the lightest profile in the XP series and is typically used when the machine requires a narrow, Cogged V-belts with high flexibility. The practical advantage of the correct profile is that the belt should neither bottom out in the groove nor be too high. When the profile fits, the load is better distributed on the sides of the belt and the belt drive has a better chance of running smoothly.

Product data

• Profile: XPZ
• Goal: 10x8MM
• Effective length: Ld 987 mm
• Inner length: 950 mm
• External length: 1000 mm
• Series: PIX X'tra® Molded Raw Edge Cogged Belts
• Construction: raw edge and Cogged V-belts
• Profile angle according to PIX data sheet: 36° ± 1°
• Mark: PIX

Length specifications

The three length specifications describe the belt's geometry from each measurement position. 950 mm describes the inner length, Ld 987 mm is the effective length, and 1000 mm is the outer length. The difference between them is due to the geometry of the belt and the measurement method. Therefore, belts with almost the same outer dimensions can still have different technical specifications.

When a belt is specified from an older marking, it is usually best to compare both the letter profile and length designation. A belt marked as XPZ 987 should not be confused with another profile of the same nominal length. Therefore, consider both Li, Ld and La together with the profile and dimensions.

With Ld 987 mm, the belt is in a common working range for many machines. Here, it is typically not only the length, but also the condition of the pulleys, center distance and correct tension that determine whether the belt drive runs stably over time.

Construction and technical features of PIX X'tra®

The PIX data sheets describe the construction with a special textile/fabric layer as a cover, a cushion rubber compound around the belt's working area, polyester cord as a tensile member and an EPDM-based compression part. In practice, this means that the belt should not only be assessed on its length. The internal construction is important for strength, flexibility, heat management and stability under load.

The main technical features of the PIX series are the timing flexibility, higher heat dissipation than a classic wrapped belt and the possibility of working in compact belt drives when the rest of the drive is correctly dimensioned. The series is also specified as antistatic, oil and heat resistant and REACH and RoHS compliant. These features are particularly relevant in machines where the belt runs for many times and is not only used occasionally.

For the XPZ profile, the PIX data sheet states the length range 550–5000 mm. This belt with Ld 987 mm is in the range 550–3000 mm, where the data sheet states a length tolerance of ±6 mm and a set tolerance of 2 mm. The tolerances are relevant when replacing, especially if several belts are to run in parallel or if the center distance can only be adjusted to a limited extent.

Use for the XPZ profile

The operating situation has a great impact on the belt's lifespan: is the belt running constantly, are there many starts/stops, is the load even, and are the pulleys clean and in good condition? This XPZ belt is designed for mechanical power transmission, but lifespan and operation still depend on alignment, tension, temperature, pulley quality, and whether the belt is installed without damage.

This XPZ belt is relevant in small and medium-sized belt drives, where correct fit and low overall height are more important than a very wide profile. In operation, the pulley groove, the belt cross-section and the timing construction are important for the contact between the belt and pulley. Profile and length must match, as correct length does not compensate for an incorrect cross-section.

Profile and pulley compatibility

XPZ belongs to the same narrow profile family as SPZ, but the belt has its own technical specification with a timing, raw-edge construction. The belt works with side contact in the pulley groove, and the correct groove profile is necessary for the contact surface, friction and load to be distributed correctly. Incorrect cross-section or skewed pulleys can cause overheating, noise, slippage and uneven wear.

The technical identification consists of the combination XPZ, 10x8MM, Ld 987 mm, 950 mm, 1000 mm and PIX X'tra®The combination distinguishes the item from nearby V-belts with other profiles, other length standards or a different construction.

Installation and operation

A new belt should be installed in clean, dry and undamaged pulleys. Oil, old belt dust, rust or sharp edges can shorten the life. Alignment between the pulleys is also important. Even a good belt can quickly wear out if the pulleys are misaligned or if the belt is forced to work sideways.

After start-up, it is wise to listen for abnormal noise and feel for abnormal heat when it is safe to do so. Slippage, whining, vibrations or black belt dust may indicate incorrect tension, incorrect profile, worn pulleys or excessive load. The fault should be found before the machine continues to run for a long time.

During continuous operation, the belt should be evaluated for ctiming bars, heavily worn side faces, glazing, frayed edges, and signs of overheating. If the belt repeatedly needs to be retensioned, it is often an indication that either the belt, the pulleys, or the setup itself should be examined. Replacing the belt alone does not always solve the cause of the problem.

During operation, the belt not only functions as a length indicator, but also as a dimensionally stable component in a mechanical belt drive. The XPZ profile, the width/height 10x8 MM and the effective length Ld 987 mm form the basis for the belt's placement in the groove. The timing underside helps the belt around the pulleys, while the rough side surfaces transmit the force. The combination is particularly relevant when smooth running and limited heat generation are important for the service life of the system.

Li 950 mm, Ld 987 mm and La 1000 mm describe three different measurement lines on the same belt. The difference between the measurements is due to the thickness and geometry of the belt, and therefore they should be seen as technical specifications rather than interchangeable length indications.

Technical questions about XPZ V-belts

What does XPZ 987 mean on this belt?

XPZ is the profile designation and 987 refers to the effective length Ld in millimeters. For this item, this means that the belt is specified as an XPZ profile with dimensions 10x8 MM, Li 950 mm, Ld 987 mm and La 1000 mm.

Why does a new V-belt get hot?

Heat is often caused by incorrect tension, misaligned pulleys, worn grooves, excessive load or incorrect profile. A correctly specified belt can still have a short life if the belt drive is not adjusted correctly.

Is external length the same as effective length?

No. La is the external length, while Ld is the effective length. They must not be mixed up because the difference may be enough to prevent the belt from being tensioned correctly.

What conditions affect the operation of the belt?

Profile, dimensions, Ld, Li, La, pulley groove, number of belts in the drive and machine operation all affect the load on the belt. When these conditions match, the belt works more stably and has a longer service life.

What do Ld, Li and La mean on this V-belt?

Ld is the effective length and is the length stated in the product name. Li is the inside length, and La is the outside length. The three measurements are used to compare belts because manufacturers and older belt markings do not always use the same length designation.

Is the length alone enough to describe the belt?

No. The length is important, but the profile is at least as important. A belt with the correct length but the wrong profile can lie incorrectly in the pulley, causing poor contact, heat, noise and a shorter life.

When making technical comparisons, length, profile, cross-section and the product's Li, Ld and La should be viewed together. This makes the difference between internal, effective and external length clear and reduces the risk of confusion between adjacent belt sizes.

Overall rating: V-belt XPZ 987 - 10x8 MM - PIX X'tra ® is specified with profile XPZ, dimensions 10x8 MM, effective length Ld 987 mm, inner length Li 950 mm and outer length La 1000 mm. The belt belongs to the PIX X'tra® series and is designed as a raw-edged, Cogged V-belts for mechanical power transmission.