Mechanical Springs and Sealing Devices: A Comprehensive Overview
Springs
Elastically used to join together pieces of equipment.
Types of Springs:
- Coil Spring Traction: The coils are next to each other. They work, stretching, by the action of forces. Typically available at the end eyelets.
- Helical Compression Springs (tapered and notched barrel): The windings keep some distance between themselves (step). By the action of external forces compressed.
- Compression Spring in Truncated Cone: In a strip with a diameter that gradually decreases.
- Torsion Spring: They offer resistance to the implementation of a torque. They are round steel wire and have many applications.
- Coiled Springs: They are constructed of flat strip or material. The spring action is performed when the free end is exerted torque.
- Leaf Spring or Bow: They absorb shock efforts. They are applied in automobiles.
- Springs Dishes: They consist of tapered annular plates with loads acting axial direction.
Manufacture of Helical Springs
When it comes to large series, the manufacturing is done in automatic lathes.
For short series uses a mandrel with a slot or a hole in the front end, for dragging the wire. The mandrel is mounted on the lathe and the wire is inserted into the hole and between a wooden jaws mounted in the holder, at the height of the dot. With the machine idling the wire is wound to form the spring.
The passage of the spring working in compression, is achieved with the advancement of the machine. Both ends are left spiral ¾ as “dead loop”.
The tension springs are wound without any distance between the coils.
Applications of Springs
In some mechanisms are irreplaceable by other elements such as safety valves, clutches, pulleys, turnbuckles, elastic joints …
Sealing Devices
They are pieces that are designed to prevent ingress of dirt and dust in axes, trees, shafts, bearings and valves. And prevent from the outer gaseous or liquid.
Types of Sealing Devices:
Shutter
- Slotted Non-Contact Seals: Concentric grooves retain small foreign bodies. They are used in simple applications and for grease lubrication.
- Labyrinth Penetrators: Compounds by one or more grooves to enhance their effectiveness, the intermediate spaces must be always full of fat. There are two types of labyrinth seals, axial and radial.
- Centrifugal Rotary: The oil that moves on the tree is discharged by centrifugal force caused by the presence of nerves, to be collected in a proper slot and taken back to the collecting chamber.
- Multiple Disks Penetrators: They enjoy preference in grease lubrication, provide a satisfactory sealing the penetration of dirt, dust and water. To enter these discs in the slot, slightly deformed in the axial and helical mounts.
- Penetrators by Rubber Caps: Use for those buildings where the space available for protegeresmuyreducido.
Sliding Shutters
- Felt Ring: Suitable for work at moderate speeds. Both felt ring slot as accommodation are normalized. The area where the felt touches must be corrected.
- Glands: A packing oakum or other textile material to be compressed by a flange radially expands.
- Seals: Lip seals are fitted with a cylindrical outer sleeve attachment, resistant synthetic rubber oil, and a sealing lip charged under the pressure of a muelle.En many cases the standard checkpoints are not sufficient to provide sealing, which is why checkpoints are usually set with striped radial torsion.
- Piston Seals: The board of piston is used in double-acting piston, axial motion, able to work in hydraulics.
- Bolsters: Sealing elements are used as rod seals.
- O-Rings: O-rings are rings of circular section. They are used for sealing between two stationary machine elements to achieve the tight junction of two elements in movimiento.Su hermetizante effect is based on the axial or radial deformation of the section. They are obtained by pressing and in rings seamlessly using elastic synthetic materials.
O-Ring Mount
Beveled edges are rounded and carefully, you should clean all surfaces of dirt and residues mecanizado.Para o-ring in place the housing, the force should be avoided passing by sharp edges, etc.. …. The o-ring should not squirm when placed in its seat.
Grease Lubrication Procedures
- Point to Point Manual Lubrication: Grease is performed by placing at each point of a bearing lubrication oil or grease to each point. This lubrication system is used only on machines that allow greasing each long periods of time. Has disadvantages in terms of design because, due to oversight, some points may be ungreased.
- Lubrication Oil Bath: Use in gearboxes, reducers and other mechanisms. With this system it is difficult to dispense the oil to lubricate the parts that interest.
- Grease Drip or Oil Spray: It consists of making the lubricating oil by dropping in the form of drops or jet over the items to oil.
- Centralized Lubrication: Consists distribute oil to each and every one of the lubrication points using a pump that can be manually operated, pneumatic, mechanical or electrical.
- Pumps: They are responsible for generating the necessary pressure so that the lubricant reaches the lubrication points.
- Pipes: For those circulating the lubricant to the lubrication points.
- Distributors: They act dosing the amount of oil in each one of grease points.
- Centralized Lubrication by Micro-Mist: It consists in transporting small particles of oil suspended in the air from a lubricator, to the nozzles or diffusers placed at each lubrication point.
Preparation of the Oil Superficies
All items will suffer slippage before to be mounted are subjected to a surface preparation for the movements are precise.
Preparation
- Grinding Mechanics: Abrasion machine consists of sliding guides for optimal surface finish. Rectified two sliding surfaces can present problems of adhesion between them.
- Scraping: It consists in creating the maximum number of contact points in a flat with another. Marble pattern are used, including through inking mark the outgoing and incoming scraping the surface. The quality of a scraping depends on the quality of marble and operator skill. The scraping is more appropriate than grinding for sliding surfaces and do not exhibit adhesion problems.
Clean Surfaces
Well before mounting the sliding guides, it is desirable that the surfaces are clean of any particles contaminantes.Los objectives pursued with the cleaning are as follows: That the dust particles, chips … not trapped between the two surfaces deslizamiento.Eliminar remains fluid corte.Eliminar the remains of old oil.
Methods Linear Guides Lubrication
Lubricación oil is lead to the sliding surfaces and is distributed across the surface in such a way as to create a movie.
- Slots or Spider Legs: It consists of making shallow grooves in such a way that facilitates the distribution of oil across the surface.
- Lagoons: Consists of making a big cavity more or less shallow so that filling the cavity to secure supplies of oil between the sliding surfaces.
Lubrication in Rolling Rotational Elements
You can lubricate with grease or oil. This grease is usually done by bombs or by fog.
- Gears: They are usually lubricated with oil drip or spray, or bath microniebla.
- Bearings: It can be lubricated with grease or oil.
Grease
Side is made bearings and bearings in an environment dusty. It is a simple and cheap. The fat should be introduced with appropriate pressure as Stauffer lubricators or grease ball.
Lubrication by Oil
That is used in bearings working at high speed and high surface pressures. The oil can be introduced through manual or automatic, it is desirable that the bearings are available in their area of grooves to distribute the oil well.