Chain and Belt Tensioning Systems
36Pages

Chain and Belt Tensioning Systems ASA/JIS Edition

Chains and belts are important wearing parts in many plants and machines. Since they are constantly moving, the stresses to which they are subjected are particularly high. Belts require pretensioning - chain links elongate and run increasingly less smoothly. Murtfeldt tensioning systems keep chains and belts reliably tensioned, thus increasing their lifetime. They are tried-and-tested following decades of use around the world. Our experience with these systems enables us to provide you with optimum advice and to always offer the best possible solution for your needs. Wide range - extensive...

FUNCTION, PRINCIPLES, HANDLING Our tensioning systems are free-running and resilient. As a result, they do not function as rigid deflectors when stressed. This avoids excessive contact pressure. Our systems aim to keep the overall force on the slack strand – resulting from the weight of the chain and the centrifugal force – under control. The ideal installation position is right behind the drive sprocket in order to keep the length of the slack strand that needs to be tensioned as short as possible. Use at extreme temperatures If you choose the correct material, you can also use our...

OPTICAL CONTROL DISPLAYS Murtfeldt Spann-Box® systems generally have a coloured scale. This enables you to determine the tensioning state of the chain at a glance. The display is as easy to understand as possible: Green The chain tensioner is working in the “green range”. The tensioning force is providing an ideal, smooth running movement. Yellow The tensioning force is not ideal but is still sufficient. F UNC T ION, PRINCIPLE S, HANDLING | OP T IC AL CONT ROL DISPL AYS Red The chain tensioner needs to be adjusted. The tensioning force on the chain is too low for a smooth and reliable...

OVERVIEW OF Spann-Box® Types Chain tensioners Spann-Boy® TS with arc segment profile – page 16 Spann-Boy® TS with sprocket – page 17 Spann-Box® size 30 page 19 Spann-Box® size 1 with arc segment profile – page 20 Spann-Box® size 1 with return profile – page 22 Spann-Box® size 1 with sprocket Type K-L – page 23 Spann-Box® size 2 with arc segment profile– page 24 Spann-Box® size 2 with return profile – page 26 Spann-Box® size 0 page 18 Spann-Box® size 1 with semi-circular profile – page 21 Spann-Box® size 1 with sprocket Type K-S – page 23 Spann-Box® size 2 with semi-circular profile – page...

Belt tensioners Spann-Box® size 1 belt tensioner with tensioning roller at top – page 31 Spann-Box® size 0 page 30 Spann-Box® size 1 with tensioning roller type SR-L – page 32 Spann-Box® size 1 with tensioning roller type SR-S – page 33 Spann-Boy® TS tensioning roller – page 29 SIGNS AND SYMBOLS Features and properties of tensioning systems Plastic housing Two pre-tensioned compression springs, tension distance specification in mm Steel housing (also stainless steel) Three pre-tensioned compression springs, tension distance specification in mm Track profile for all large chains Further...

GRAPHICAL DEPICTION OF INSTALLATION EXAMPLES Popular but non-optimal arrangement, tension distance not used efficiently 180° return profile. This arrangement allows a particularly long chain length to be accommodated. Omega tensioning station – ready-to-install system If the running direction changes, we recommend using two Spann-Box® units near to the drive. Optimum, extremely efficient chain support/tensioning Return/tensioning statio

Smooth running is a decisive factor for the long lifetime of a chain. We therefore recommend the use of a chain tensioner with a slide profile. Advantage: Protects the chain links and provides a quieter, safer movement. We are happy to provide detailed advice if you inform us of the required criteria. our Web site at www.murtfeldt.com contains a design questionnaire that you can use to enter all required data. IMPORTANT CRITERIA WHEN SELECTING THE BEST CHAIN TENSIONER FOR YOUR NEEDS Axis-centre distances of sprockets Chain design Constant/changing running direction Chain speed Chain...

1) It is possible to use several types of SPANN-BOX® alongside each other with duplex or triplex chains. 2) Slide profile or return pulley with U-profile. Simplex chain EXPLANATION OF SYMBOLS Profiles symbols for selection tables Arc segment profile ■ Slide profile shape with optimum mechanical properties ■ Simultaneous contact with several rollers ■ Optimum chain protection Return profile ■ 180° change of direction ■ The 180° change of direction permits the dual use of longer tension distances.

Duplex chain Triplex chain ■ Contact with only very Block profile Suitable for particularly heavy chains and high mass forces slide profile and tension core made from a single piece Semi-circular profile Roller/sprocket For small changes of direction For high chain speeds ( > 1 m/s) Excellent stability ■ Recommended where 300 mm slide profile ensures support for many rollers with space is at a premium chains with large chain pitches

We offer various mounting brackets to make assembly more easy. They provide additional modification/adjustment flexibility. Elongated mounting holes allow easy adjustment if the normal tension distance has already been used up. Alignment errors can be corrected by side movement.

Eckenradius erlaubt Die Zeichnung ist unser Eigentum. Sie darf weder vervielfältigt noch an Dritte weitergegeben werden. Maßstab: 1:1 Allgemeintoleranzen für Längenmaße nach 50 DIN ISO 2768 mittel Name Gez. Ullenboom Gep. Szymlek -Kanten manuell abrunden Murtfeldt Kunststoffe GmbH & Co. KG Heßlingsweg 14-16 44309 Dortmund Tel. +49-231-20609-0 ● Fax. +49-231-251021 www.murtfeldt.de Name Gez. Ullenboom Gep. Szymlek Murtfeldt Kunststoffe GmbH & Co. KG Heßlingsweg 14-16 44309 Dortmund Tel. +49-231-20609-0 ● Fax. +49-231-251021 www.murtfeldt.de Die Zeichnung ist unser Eigentum. Sie darf weder...