Couplings are critical components in rotary motion systems such as driveshafts, generators, and motors. In these applications, couplings join two shafts together to stabilize them against shock load and overload. The joint between shafts can be temporary or permanent.
As an ISO 9001:2015-certified manufacturer, Stafford Manufacturing Corp. is a leading supplier of standard and custom rigid shaft couplings. Our quality products support a full range of OEM and MRO applications in both industrial and consumer settings.
What is the Role of Couplings?
Couplings are defined as mechanical components used to connect two shafts. They serve primarily to transmit energy from the drive side to the driven side of a rotary system, and secondary functions include compensating for misalignment or reducing vibration.
There are two main types of couplings: flexible or rigid. Flexible couplings have greater freedom of motion at the connection point, so they can withstand lateral and axial forces better than rigid couplings. Greater flexibility means decreased torque transmission, so these couplings are best for applications involving some degree of misalignment between the shafts.
Rigid couplings, on the other hand, create an inflexible connection between two shafts. As a result, they can transfer torque more efficiently than flexible couplings. Shafts must remain in precise alignment, since the coupling cannot flex to compensate for deviations. As long as proper alignments are met, rigid couplings offer a secure, precise, and effective means of transmitting power.
Stafford specializes in the high level of precision necessary to produce rigid couplings that are long-lasting and reliable.
We manufacture four main styles of rigid couplings in a variety of materials for both english and Metric shafts. In addition, we offer various bore configurations, including round, square, and hex.
Offering straight-through or stepped bores, these rigid couplings enable the transfer of rotary motion from the driving shaft to the driven shaft. They maintain high torsional stiffness and can offer support and extension to shafts.
These feature a two-piece clamp for easier installation and adjustment. Two-piece couplings offer the same advantages of one-piece couplings but with the additional ability to service the coupling without removing it from the assembly
Three-piece couplings allow greater control over positioning. They maintain the position of one shaft while changing or adjusting the other.
Precision sleeve couplings provide a closer fit with an axial runout of less than 0.001 inch TIR. As a result, these couplings allow users to pair two shafts with no backlash or axial motion.
The ideal coupling depends on your speed and torque requirements, as well as the shafts’ diameters, alignment, and configuration. Stafford offers a standard line of round, square, and hexagonal bore couplings for a variety of applications including food processing and conveying.
How Does a Coupling Work?
Couplings work by securely clamping two shafts together, allowing one shaft to transfer energy to the other. At the same time, the coupling absorbs shock, vibration, and heat generated by the first shaft, protecting the surrounding components while still effectively transferring torque.
Installing a rigid coupling allows two separate shafts to operate as one. Their high torsional stiffness allows no relative motion between the shafts of the driving and driven units. Eliminating relative movement maximizes the amount of torque that can be transmitted across the shafts.
Applications for Couplings
Couplings are used across a wide range of power transmission and rotary motion applications. They are often found in pumps, mixers, drive shafts, and turbines. Rigid shaft couplings are used in systems with aligned shafts, especially where the application requires zero backlash.
Rigid couplings can fill any of the following application requirements:
A rigid coupling allows a driving shaft to support a driven shaft. This is important when the driven shaft is not bearing-supported.
Rigid couplings connect precisely-aligned shafts having the same or different diameters.
A rigid coupling can be used to connect two shorter shafts, allowing them to act as one longer shaft.
Maintenance of high torsional stiffness
Rigid couplings produce zero backlash and zero axial motion, so they are ideal for maintaining high torsional stiffness along a system’s rotational axis.
Applications with these requirements are found in many industries, including:
Food and beverage
Advantages of Rigid Couplings
Rigid couplings are simple, cost-effective components that keep equipment running properly. The following are other advantages of rigid couplings, especially compared to flexible couplings.
Precision: Rigid couplings have no backlash or windup, so they offer greater precision than flexible couplings. Stafford also offers special precision sleeve couplings to meet the strictest tolerance requirements.
Positioning: Rigid couplings’ high torsional stiffness maintains optimal positioning between connected shafts.
Torque transmission: Rigid couplings offer excellent torque transmission capabilities that exceed those of flexible couplings.
Alignment: Rigid couplings establish and maintain optimal shaft alignment between a motor and its driven units.
Versatility: A wide range of applications can benefit from rigid couplings, which facilitate both push-pull and support applications.
Ease-of-use: Clamp couplings are designed for easy installation and maintenance. This is especially true for two-part and three-part models, which allow for in-place maintenance and adjustment.
Used in the right settings, rigid couplings ensure smooth, efficient performance across power transmission applications.
Stafford’s Rigid Couplings
Rigid couplings provide excellent torque, high torsional stiffness, and minimal backlash. As specialists in rigid couplings, Stafford offers a full catalog of one-piece, two-piece, and three-piece couplings in high-strength, low-profile, and heavy-duty profiles. All of our components are smooth and mar-free, offering maximum performance with no damage to shafts.
Our full focus on rigid couplings allows us to offer high-quality products with industry-leading features. For clients with strict tolerance requirements, we offer precision-sleeve couplings that maintain less than 0.001 inch TIR concentricity while in use. We also offer an innovative PowerRing line, which achieves three times the load capacity of other heavy-duty collar couplings.