Alb Mod Couplings Flashcards
Shaft couplings are _______ components used to connect the driving and driven shafts end to end
power transmission components
Couplings should be capable of transmitting the maximum ___ and ___ for the intended application
torque and power
The three types of couplings are: (3)
- Rigid
- Flexible
- Special purpose
A ____ coupling does not allow for any deviation in the alignment of the shafts and does not permit end float
rigid
This coupling is a very simple rigid coupling. Used at low speeds and low torque, consist of heavy walled tube with a keyway and holes/threads for set screws
sleeve coupling
This rigid coupling grips the shaft using tapered sleeves inside of tapered hubs. The hubs are drawn together with bolts, and in doing so, clamps itself to the shaft. Good for light to moderate loads and can accommodate two different shaft sizes.
Compression coupling
This rigid coupling is used in heavy load and torque applications. The two halves of the coupling are split parallel to the shafts axis and require keyways machined in both shafts. Made of steel or cast iron, the torque is transmitted via the keys, the clamping of the coupling merely holds it all together. Can be special made for different size bores
ribbed coupling
This rigid coupling has two flanged halves that are bored and keyed to fit the shaft. They can be mounted on different diameter shafts. In some cases, the hubs are a machined part of the shaft. The hubs are made with male and female surfaces and close fitted bolts. In light duty applications, can be mounted with an interference fit.
Flange-faced couplings
This rigid coupling is commonly used on vertical pumps where the drive is connected via a series of drive shafts. Shafts rotate in the direction of the threading. Lubricant or anti seize is recommended. Steady bearings can eliminate shaft whipping and vibration
Threaded couplings
This type of coupling will compensate for some misalignment, either through mechanical or material flexibility. Most common couplings.
Flexible coupling
Mechanical flexibility is:
flexibility achieved through designed clearance between coupling parts, allows a sliding motion
Material flexibility is:
flexibility achieved through the bending or compressing if a coupling material
Mechanically flexible couplings have very little:
torsional flexibility
The three types of chain coupling are:
- Roller chain
- Silent chain
- Synthetic chain
This flexible chain coupling has two sprockets keyed to the shafts and a length of standard pitch roller chain connecting them. Chain is usually made of high tensile, heat treated steel and the sprockets are hardened for maximum wear. Can use double strand or single strand roller chain. Single strand offers more end float. These couplings are suitable for moderate speed/power
Roller chain coupling
This flexible chain coupling is usually recommended for heavy-duty drives at speeds of up to 5000 RPM. Chain is wrapped around two wide sprockets. Allows for minor misalignment and some end play. Is more balanced, smooth and quiet.
Silent chain coupling
This flexible chain coupling operates quietly and smoothly and is usually used for light power drives. Chain is made from plastic or nylon. More common in food processing. Links do not require lubrication and are not conductive. Can be used in corrosive conditions of pins are stainless. The chain material allows for some torsional flexibility.
Synthetic chain coupling
This flexible coupling consists of two identical hubs with external gear teeth and a cover that has matching internal teeth. Allows for axial float and some angular and offset misalignment. Needs to be lubricated. Steel for high torque loads and plastic for low HP uses. Tooth profiles can be straight tooth or curved tooth
gear coupling
With a gear coupling, which allows more misalignment? curved or straight teeth?
curved teeth
Material flexible couplings use what materials? (5)
- Rubber
- neoprene
- plastic
- nylon
- flexible metal elements
This flexible coupling uses a flexible rubber element. Either clamped together or molded directly to the steel rims. Driving element can be changed without changing the hubs. Can reduce shock and vibration. Excellent torsional flexibility and can allow any type of misalignment and end float.
Rubber tire coupling
The rubber tire coupling can be made smaller and more compact, but are more difficult to install and have less torsional flexibility. What is it called?
bonded rubber coupling
This flexible coupling transfers torque through an elastometric element, bonded to metal inserts that bolt to the hubs. Insert unwraps and allows easy installation. Insert can be swapped without disturbing alignment
elastometric coupling
This flexible coupling uses a rubber or neoprene biscuit molded to steel sleeves. Allows for deflection, torsional flexibility and axial float
pin and biscuit coupling