Daily spot check works even if should pass “ the equipment of ” of law of check of 5 feeling spot that monitor runs state, undertake in time judging eliminating to breakdown. Be opposite through 5 feeling commonly the scroll sound of the bearing in movement (noise) , the examination project such as temperature, vibration and lubricant condition undertakes judging.
“ 5 feeling ”
The feeling of the eye that points to a person, ear, nose, hand, mouth
5 feeling of “ nod check ”
Basically be to be in equipment movement around or movement, reach by right of 5 feeling jointly by check of operation, spot, moving tripartite listen to a few simple assistor such as hammer of phonic club, examination, thermometer to provide, according to the cycle of set and place, rely on visual, ear to listen, nose smell, hand is touched, the mouth is tasted, sound of examination and the pressure that master equipment, temperature, discharge, leak, state giving fat, different, oscillatory, chap (fold caustic) , wear away, a kind of method that waits for element flabbily.
One, the method that 5 feeling of “ choose check ”
1, visual
According to statistic, the 60 ％ of the person’s action begin from the perception of “ vision ” . Visual suitable scope is extremely wide, all sorts of examinations all but from visual the law begins. For example from bearing coating burst, on bearing, fault of earmark of joint issueing tile is moved, can discover bearing become loose; It is normal that the change that watchs oil level and oily scene understands lubricant system to move; From scorch, burn become angry, fall off, eyewinker, dust, craze, considerable examine is electric yuan of blemish inside parts of an apparatus. With visual when the law is checked, must have serious and meticulous observation, if check electric ark when, not only should see dish of face, and should open cupboard door further, have observation from each angle; When checking electric machinery, not only should see electric machinery case, and can make germinant top, state of farther observation commutate and scintilla grade.
2, ear listens
The person is quite sensitive to the stimulation of sound wave, listen to phonic law to basically differentiate different sound and normal audio distinction.
Bump mechanically, the attaint of bearing, the happening of eccentricity and machinery of high speed circumgyrate are acuteness add decelerate, a series of oscillatory source can cause all sorts of components to become loose, produce all sorts of unusual concussion sound or irregular noise.
The behavioral voice of relay, contactor, electric machinery rotates the sound, electromagnetism sound of transformer has its peculiar normal voice, listen to be used to after these normal sound, easy discovery is unusual after comparing. Additional, a few dormant parts of an apparatus, for example plug-in unit board, receiving plug-in unit do not phonate originally, but if hear voice of ” of bang of bang of Pi of Pi of some kind of “ ,be about to notice, because this often is by contact undesirable, screw or receive insert become loose, or electric current passes to wait for unusual place to cause greatly.
After hearing different news, want the connection of aggrandizement and other feeling, or have the aid of listens the examination method such as phonic club, in order to determine unusual position.
3, nose smell
Smell is in “ is removing important matching to combine function in law of ” of check of 5 feeling spot, strange flavour of nose smell out shows equipment has for certain unusual. Nose smell law basically is checked scorch wait for the off-odour that cause, if commonly used and electric equipment is of no wonder odour originally, appear so strange flavour is very easy fish, not be relay, electromotor coil happening circles a short circuit, be isolated from namely ageing burn down. Because produce these,circumstance hind causes fire extremely easily, because this needs to find out unusual drop quickly, want to stop machine processing when necessary.
4, the hand is felt
Touch and vision, hearing is close correlation. It is main examination temperature, vibration and pollution that the hand is felt. Temperature is exorbitant not only be isolated from quickly deterioration, shorten insulation life. Cause person easily still to get an electric shock, burn the accident such as caustic, and drop to electronic loop function the effect that has particularly apparent.
5, the mouth is tasted
Use “ when 5 feeling ” orders check, use an ambassadorial method not quite normally, although be in,special situation is badly in need of differentiating acidity or alkalescent when, also must be in ensure the premise that does not have an influence to the body falls, discretion is used.
2, 5 feeling of “ nod check ” [listen to phonic judgement to roll bearing should be nodded unusually]
According to dimension size and locomotive speed, scroll bearing is having the distinctive voice of oneself. If can assign the account that clear and the following sound produces, to judging bearing ahead of schedule injury has very great help, .
1. Raceway sound
Raceway sound is body of the scroll when rotating as a result of bearing roll in raceway and arouse a kind smooth and successional noise, become its only sound pressure level or tonetic and great when just cause people to notice. The sound energy that actually raceway sound place arouses is finite, if be below normal circumstance, reputation of excellent 6203 bearing raceway is 25 ～ 27dB. This kind of noise with bearing the sheet of radial load lists deep trench ball bearing to be the most typical
It has the following characteristic:
Noise, vibration has random sex;
Oscillatory frequency is in 1kHz above;
No matter how does rotate speed change, noise advocate frequency changes scarcely and sound pressure level increases along with rotate speed and rise;
When radial windage increases, sound pressure level increases quickly;
Bearing tigidity increases, total sound pressure level is lower, although rotate speed is elevatory, its total sound pressure level also increases not quite;
Lubricant viscosity is taller, sound pressure level is lower, but lubricant to fat, size of shape of fibrous of its viscosity, black all can affect noise value. Source of raceway sound generation depends on getting the ferrule after load is inherent and oscillatory be caused by. Because ferrule is mixed,the stretch contact of scroll body is formed nonlinear oscillatory system. Should lubricate or the inherent vibration that as stretch as this feature concerns can be aroused when treatment precision is not tall, noise turns into in delivering air.
Well-known, even if used the most excellent now production technology to machine bearing spare parts, its job surface always can exist the tiny geometry error with differ degree, make tiny wave motion arises to stimulate oscillatory system between raceway and scroll body thereby inherent vibration. Although it is inevitable, can adopt high accuracy to machine surface of spare parts job however, choose bearing correctly to reach what use bearing accurately to make to fall a confusion of voices is decreased brace up.
2. Sound of falling body scroll
This noise usually, appear below low rotate speed mostly and bear the large bearing of radial load. Run below radial load when bearing, area of the load inside bearing and blame load area, when be like bearing to have certain and radial windage, the scroll body that is not load area and inside raceway is not contacted, but because leave the action of mental efforts likely,contact with outer lane, for this, below low rotate speed, be less than scroll when centrifugal force when body is self-prossessed, roll experience falls and with inside raceway or cage collide and the inherent vibration that arouses bearing and noise
Have the following characteristic:
When fat is lubricant easy generation, oil-lubricated when not easy generation. Arise more easily when using inferior grease.
Winter often happens.
To action radial load and when radial windage is bigger easy also generation.
In some also can arise inside specific limits and the bearing of different measurement its speed limits is different also.
The likelihood is successive sound Yi Ke can be intermittent sound.
Should force oscillatory Chang Ji to send outer lane 2 rank, 3 rank curve inherent vibration, give out this noise thereby. Through using preload method of carry on one’s shoulder can reduce this noise effectively, reduce windage of radial of job of the bearing after outfit machine, choose good lubricant to be able to be improved somewhat, some abroad enterprise uses light-duty scroll system, if the technical measure such as roller of pottery and porcelain or hollow roller comes,prevent the generation of this kind of noise.
3. Pointed song
It is the scream with quite fierce generation of the sliding friction between the metal, although bearing temperature rise is not right now fast, also do not have to bearing life and grease life how old influence, also do not affect rotate, but vinegary ear sound is disturb, bear especially the bearing of large short columnar roller of radial load often has this noise
Its characteristic is:
When bearing radial windage is big easy generation.
In appearing in fat to lubricate normally, oil-lubricated more infrequent.
Increase as bearing dimension and reduce, and often appear inside limits of some rotate speed.
Winter appears constantly. E. Its occurrence is ruleless, and unpredictable, and reach condition of movement of function, installation with the quantity that fill fat concern. This kind of noise can be used reduce bearing radial windage and use shallow spend structure of outer lane raceway to prevent.
4. Cage sound
Rotate in bearing vibration and it and scroll body or ferrule photograph bump the freedom of the cage in the process to be able to give out this noise. It appears possibly in of all kinds bearing, dan Jisheng approachs level not quite tall and be low frequency.
Its characteristic is:
Punch cage and plastic cage all can arise.
It is rare oil or fat lubricate to all can appear no matter.
Bear when outer lane when curved quadrature happen the most easily.
When radial windage is big appear easily.
Because cage wraps up aperture clearance and cage and ferrule clearance to be in bearing finished product,want inevitably to exist, because of this comb-out cage sound is very difficult, but can assemble an error through decreasing, actor chooses reasonable clearance and cage change momentum to improve.
Another kind of cage is special because cage and other bearing spare parts guide the blatant sound that the attrition between the face causes the self excited vibration of cage and produces,sound is. The punch cage of deep trench ball bearing is thinner, the flexural rigidity inside radial and axial plane is inferior, integral stability is poor, when bearing high speed rotates, can be out of shape because of bending and produce self excited vibration, cause ” of “ bee song.
Fall in radial load action when bearing and below the condition with grease poor performance, locomotive initial stage can hear the noise of ” of “ Ka Ca, Ka Ca, because roll body is in,this basically is after leaving load area, the noise that scroll body is quickened suddenly and gives out with cage barge against, this kind of clash is inevitable but disappear as the meeting after running for some time.
Prevent cage noise measure to be as follows:
1, to make cage revolution motion stable, should use ferrule guiding means as far as possible and notice to give those who lead a side is sufficient lubricant, the structure of tapered roller bearing that dismantles to high speed operating mode gives improve, the Z that rib of ferrule of instead of the L of roller guiding cage guides cage.
2, when bearing high speed rotates, the bearing with big gap wrapping up aperture amplitude of its cage vibration is ambitious at wrapping up the cage vibration with aperture little space amplitude, it is important that so bag aperture clearance takes value blame to be. Want to notice to reduce radial windage as far as possible. Rise as far as possible maintain valence to make precision, improve cage surface quality, be helpful for reducing scroll body and cage to produce collision or the noise that attrition produces.
3, use actively clean a technology advancedly, mix to spare parts add up to the product after covering to undertake effective and complete clean, those who raise bearing is clean.
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4, run below radial load action when bearing, its interior has only a certain number of scroll system stands load, because contact the bearing of “ bedspring ” that form to make roll body is in with the flexibility of ferrule,passed line of radial load action to produce periodic vibration, and because the prolapse on this meeting moves continuously or runner shaft center does horizontal way to move, cause noise at the same time.
This kind of vibration says pass vibration for scroll body, behave when low speed runs especially more apparent. And its amplitude criterion type, as radial as bearing load, radial windage and scroll body amount are concerned. This amplitude is normally lesser, be like the ability when amplitude is big to form a harm, often use for this reduce radial windage or bring to bear on proper preload carry on one’s shoulder will reduce.
