Printing

Ruland offers an industry-leading selection of one -and two-piece shaft collars often used in printing applications. Ruland shaft collars have precisely controlled face to bore perpendicularity (TIR ≤ .002" / .05mm) which is critical for proper alignment when collars are used as a load-bearing face or guide for large rolls of paper. Clamp style shaft collars do not mar the shaft, are infinitely adjustable, and have higher holding power than set screw shaft collars. Ruland mates halves of the two-piece collars throughout the manufacturing process to ensure a precise fit and maintain high holding power.
Designers prefer clamp type shaft collars in printing due to the frequent nature with which paper, rollers, and other fixturing need to be changed out or adjusted. Traditional round bore shaft collars are the most used because of their high holding power and relative cost effectiveness. Ruland also offers two forms of quick clamping shaft collar – with cam lever and with clamping lever – giving system designers the option to change out or adjust system components quickly.
Ruland shaft collars fit shafts from 1/8” to 6” and 3mm to 150mm. They are made from select North American bar stock in 303 & 316 stainless steel for corrosion resistance, 1215 lead-free steel for high holding power, high-strength 2024 aluminum for lightweight, and engineered plastic for corrosion resistance and light duty applications. Ruland manufactures shaft collars in our Marlborough, MA factory under strict controls using proprietary processes.

Rigid couplings are manufactured from a single piece of material with no flexing elements for the greatest torsional stiffness and torque of any Ruland coupling. This makes them ideal for applications that require high accuracy and repeatability. These performance characteristics make rigid couplings well suited for large format, 3-D, and other types of printers in which no shaft misalignment is present. Most printing system designers prefer to use clamp type as opposed to set screw rigid couplings because they have increased holding power, will not mar the shaft, and have standard aluminum options for lightweight and low inertia.
Ruland manufactures rigid couplings with precision honed bores on straight bore couplings to ensure collinearity for a precise fit and increased torque transmission capability. Collinear bores prevent the coupling from introducing misalignment into systems where it would not otherwise be present allowing for reduced wear on joined components and increased system efficiency. Clamp type couplings have proprietary Nypatch® anti-vibration coating on hardware to prevent screws from coming loose during operation, allow for repeated screw insertions, and provides the necessary dissimilar material in stainless steel to prevent galling.
Rigid couplings are manufactured by Ruland in set screw and one- and two-piece clamping styles in 1215 lead-free steel with a black oxide finish for high torque, lightweight 2024 aluminum for low inertia, and 303 stainless steel for corrosion resistance. Bores are available in sizes from 1/8” to 2” and 3mm to 50mm. Ruland manufactures rigid couplings in our Marlborough, MA factory under strict controls using proprietary processes.

Ruland oldham couplings are a three-piece assembly with a balanced, high RPM design comprised of two anodized aluminum or stainless steel hubs and a center disk. Designers can choose between acetal, Nylon, and PEEK center disks to balance torsional rigidity, torque, and environmental compliance. Ruland uses a proprietary machining process to ensure smooth interaction between the oldham coupling hub tenons and disk allowing for the longest service life in the industry. Oldham couplings accommodate significantly more parallel misalignment (up to 10% of the outer diameter) than any other Ruland servo coupling.
Due to their three-piece design oldham couplings be easily assembled and taken apart. This makes them ideal in printing applications with rollers that are frequently changed and replaced. Operators need only remove the center disk before separating shafts, saving significant time when compared to one-piece couplings that require tools to remove and install. If coupling failure occurs the center disk will act as a torque limiter by breaking cleanly and ceasing power transmission, potentially protecting expensive machine components. In this event operators can quickly and easily replace the relatively inexpensive disk to quickly return to normal operation.
Bore sizes are available from 1/8” to 1-1/8” and 3mm to 30mm. Oldham coupling hubs are available in clamp and set screw styles with or without keyways, allowing designers to mix and match hubs to fit different shaft types. All oldham couplings have a balanced, zero-backlash design for reduced vibration and precision operation.

Ruland bellows couplings are made of two lightweight anodized aluminum hubs joined by a flexible stainless steel bellows creating a low inertia, zero-backlash coupling. The thin walls of the bellows allow the coupling to flex under misalignment while remaining rigid under torsional loads. Engineers designing large format printing systems often prefer to use bellows couplings because they are lightweight, accommodate all forms of misalignment, and have the greatest size-for-size torque and torsional stiffness of any Ruland flexible coupling. Their high torsional stiffness and balanced design is critical in large format printers to prevent banding.
Ruland manufactures bellows couplings with balanced design for reduced vibration at speeds up to 10,000 RPM. They are available in clamp and set screw hubs with or without keyways in bore sizes ranging from 1/8” to 1” and 3mm to 25mm. Ruland bellows couplings are manufactured in our Marlborough, MA factory under strict controls using proprietary processes.

Ruland disc couplings are zero-backlash and have high torque, torsional stiffness, and a balanced design making them an ideal fit for a variety of printer systems. They are offered in single and double disc styles for different design requirements. Single disc couplings are comprised of anodized aluminum hubs and stainless steel disc springs. They are well suited for applications with envelope constraints, but designers must be careful when using them as they cannot accommodate parallel misalignment. Double disc couplings are made of two anodized aluminum hubs, an anodized aluminum or acetal spacer (for electrical isolation), and stainless steel disc springs. The double disc style is designed to accommodate more misalignment than the single disc style, including parallel misalignment.
Disc couplings have similar performance characteristics to bellows couplings with slightly reduced torque capabilities. In exchange, disc couplings offer superior misalignment capabilities. Their stiffness is high enough to prevent banding in applications such as large format printers. They are well-suited for other printing systems that require high torque and speeds up to 10,000 RPM. Disc couplings from Ruland are available in clamp and set screw hubs with or without keyways in bore sizes ranging from 1/8” to 1-1/4” and 3mm to 32mm. They are manufactured in our Marlborough, MA factory under strict controls using proprietary processes.