Piezoelectric acceleration sensors can be installed in several ways

With the rapid development of science and technology, industrial and

agricultural production, national defense construction, a large number of

engineering vibration problems continue to appear, piezoelectric acc leration

sensor in vibration and impact testing more wide used, it can not only or vibration

acceleration measurement or monitoring to provide a means, but al o for the need

to solve the vibration phenomenon of engineering to provid ate and reliable

test data and technical support, therefor wto correctly install and select the

appropriate type of sensor is particularly important.

Each installation mode of the piezoelectric leration sensor will affect

the high frequency. Before installation, the surfac the sensor in contact with

the tested part should be treated.The surface is quired to be clean and smooth,

the roughness should be less han 0.01mm, nd th axis of the installation screw

hole should be consistent wi e test d on.If the installation surface is

rough, some lubricants such as vacuum sil cone grease, heavy mechanical oil, beeswax

can be coated on the con urface to mprove the installation coupling and improve

the high frequency respon e

When eas ng the impact, because the impact pulse has a large transient

energy, the con ion between the sensor and the structure must be very reliable,

and it is best to install steel screws.

If the site env nment (such as installed on the motor, engine and other

equipment with large el ical noise) needs to be single-point grounding, in order

to avoid the impact oelectric loop noise on measurement, the acceleration sensor

should be taken to in late the component installation measures (such as insulation

screws), or the acceleration sensor can meet the test requirements of its own

structure insulation to the ground.Now the four installation methods are introduced

in detail.

1. Screw installation

The axis of the installation screw hole should be consistent with the test

direction, and the depth of the thread hole should not be too shallow, so as not

to screw the installation screw into the sensor too much to cause bending of the

base and affect the sensitivity.Each piezoelectric acceleration sensor is equipped

with a steel mounting screw M5 (or M3) before delivery, which can be used to fix

the acceleration sensor and the object to be tested.The recommended mounting torque

is 20kgf.cm for the M5 mounting screw and 6kgf.cm for the M3 mounting screw.After

installation, the sensor and the mounting surface should be tightly fitted without

gaps.

2. Installation of magnetic mounting seat

The magnetic mounting seat is divided into two kinds: ground insulation and

ground non-insulation.In low frequency and sma cceleration te t test, if the test

object is not suitable for drilling mounting screw holes (such as machine tools,

engines, pipelines, etc.), the magnetic m nting m unt provi onvenient method

of sensor installation.If the measured su is flat and steel structure, it can

be installed directly;If the tested surf e s not flat or m gnetic, it is necessary

to glue or weld a steel pad on the tested surf e to absorb t e magnetic seat.However,

it should not be used when the acceleration exceeds nd the temperature exceeds

200℃.

3, adhesive installation

A variety of adhesives can be used for bonding. The bonding surface should

be smooth and smooth, he bonding surface should be cleaned according to the

bonding process.Currently commonly 502 adhesive bonding process is as follows:

(1) F rst 200-400# sandpaper to polish the mounting surface;

(2) Clean the polished surface with acetone or anhydrous ethanol, and dry

it thoroughly;

(3) Drop an app ate amount of 502 quick-drying glue on the bonding site,

and then press the or for a few seconds with the hand (or pressure), release

the hand (or remove pressure) after the initial solidification of the glue, and

stand for more than ten seconds, so that the glue is completely cured to reach the

bonding strength;

(4) To remove the sensor glued on the measured object, please apply acetone

before the adhesive part, after a few minutes with the screwdriver to remove, pay

attention not to too hard!If the gentle force can not be taken, can be coated with

solvent, wait for a few minutes and then gently take off.

For the measurement of the great speed, please calculate the bonding

strength.The adhesive installation diagram and frequency response curve are shown

in Figure 5 and Figure 6:

4. Probe installation

Handheld probe installation is a convenient installation method when the

above reliable installation method cannot be adopted due to the narrow test surface

or rapid inspection of the equipment.Due to th w installation resonant frequency

of this installation method, it can only be used for testing below 1000Hz.

Note on installation of piez lectric acceleration sensor

1. Vibration measurement does not eed to consider the polarity of the

accelerometer. When impact measurement, it is ne y to know whether the

following three meters have requi ements for polarity.

2. The bottom surfa th sensor ter grinding finish "3μm, the user

should also be the surface of th measured onent grinding, improve the finish

and flatness. The instal ation hole of th test component to determine the depth

of the bolt, installati orque should b appropriate, in the sensor and component

joint surface, the best coated wit yer of silicone grease, increase contact,

and the high frequency response of the sensor will also be improved

3. For lar e ultra-low frequency sensor, screws can be gently screwed by

hand when they are insta ed.The ground pulsation test can be carried out on any

horizontal surface of his kind of sensor with dead weight.

4. For the sensor mounted with screw, the recommended installation torque

is 3Nm.

5. Installation tooling and protection for special sites, sometimes to make

some accelerometer mounting blocks.If the sensor needs to be floating, the

installation adapter block of insulating material can be adopted to make it insulated

from the measured object, or the insulating product can be selected.When the

accelerometer is used in a humid place, seal the connector to ensure good insulation.

It is recommended to use 703 silicone gel.Use in water to choose waterproof

products.Industrial site online installation can be used in the form of protective

cover installation.Of course, the specific acceleration sensor products, should

also choose to use the appropriate installation, so as not to cause unnecessary

losses and trouble.