Extensometer calibration equipment for measuring tensile deformation of metal materials Calibration instrument can come with verification certificate Youjin

The GWB-2000 extensometer calibration instrument is a purely mechanical high-precision displacement micrometer. According to the requirements of the JJG762 extensometer calibration regulation, it is specifically used for calibrating various types of extensometers, and is also widely used for calibrating displacement sensors and corresponding dial gauges and micrometers.

1Structural characteristics and reading method

• This instrument consists of a precision differential probe and a measuring bracket. The calibration instrument is designed with a modular structure. By combining the precision differential probe and support arm in various ways or positions, and equipped with extended column attachments, as well as various forms of separated samples such as cylinders, plates, and blades, it is convenient to calibrate various specifications and models of extensometers. Users can also configure specialized accessories for precise micro deformation measurement according to their special testing needs.
• The precision differential probe consists of a sliding measuring rod, a measuring rod sleeve, an inner reading cylinder, an outer reading cylinder, and a high-precision threaded pair. Its large range is 30 mm; Zui small graduation (cursor graduation) 0002mm; Rotate the outer cylinder by 0.002mm.

The displacement change reading is:

L=(a+0.001b+0.0001c) - (a0+0.001b0+0.001c0)

Among them: a - Inner cylinder millimeter scale reading

B - Reading of outer cylinder scoring line

C-Vernier scale reading

A0 b0 c0 is the reading before the corresponding displacement change

2、 Various technical indicators

1. Measure the gauge range of the extensometer Lmax 500 mm

2. Measure the installation aperture of the support arm on the support φ 10; φ twenty-eight

3. Differential probe reading inner cylinder axial scale 0.5 mm/grid

4. Differential probe reading inner cylinder vernier scale 0.0002 mm/grid

5. Differential probe reading outer cylinder circumference scale 0.002mm/grid

6. High precision differential probe accuracy indicators

Calibration instrument display error:

Range within 0.5 mm ≤ 0.5 μ M absolute error

Range above 0.5 mm ≤ 0.10% relative error point by point

Reference standards:

JJF1096-2002 Calibration Specification for Extensometer Calibrator

ISO9513:1999 Calibration of extensometers for uniaxial testing of metallic materials

JJG762-1992 Verification regulation of extensometers

Capable of calibrating a 0.5 level extensometer

 3、 Instructions for use

Please verify the extensometer according to the JJG762 extensometer verification regulation and the JJF1096 extensometer calibrator calibration specification requirements:

1. Select a separate sample that is basically consistent with the test sample based on the specifications and models of the tested extensometer and the test sample specifications.

2. Adjust the position of the two measuring arms to obtain a suitable calibration space; Adjust the position of the eccentric circlip on the two measuring arms to ensure that the two separated samples are coaxial; Adjust the distance between the micrometer head and the lower base to ensure the effective travel of the micrometer head. After all adjustments are made, pay attention to tightening all necessary fastening parts. During the calibration process, except for the parts that are allowed to move and move, no sliding or loosening is allowed.

3. Selection and testing of the calibration range and detection points of the extensometer:

(1) The verification range should be determined based on the technical parameters of the material to be tested by the extensometer. For example, using a 50 mm gauge extensometer to test steel specimens σ P0.2 technical data, please choose a calibration range of 1mm. If measuring the value of n, a calibration range of 25 mm needs to be verified.

(2) The selection of inspection points is generally not less than 8 points per range. For the above example, within a calibration range of 1mm, it is recommended to calibrate 10 points, that is, one point every 0.1mm.

(3) When calibrating an extensometer, it is necessary to use the integer scale multiple reading method. Do not use a vernier to estimate the reading or the decimal tail reading, as each ten point reading has caused fatigue in the reading. Estimating the reading or the decimal tail reading can exacerbate measurement errors. The integer single scale line is the clearest, simplest, and most accurate method for integer reading, with the lowest probability of error. Even if it occurs, it will be detected in a timely manner. Because the error of the integer scale multiple reading will increase exponentially, the error value of the extensometer will also increase, and this coarse error will be detected quickly and in a timely manner.

4. Use of extended column: When using the basic column to verify the extension time and cannot guarantee the gauge space of the extension meter, remove the protective cap on the basic column, insert the extended column into the main column and align it with the V-shaped groove, and tighten the screws. Be sure to tighten it before use.

4、 This instrument is equipped with measurement accessories

1. Two combination calibration rods. Used to combine multiple simulated separation samples.

2. 4 blades. Installed on a combination calibration rod: used for COD or JIC clamp gauge verification.

3. Two horizontal test pieces. Installed on a combined calibration rod: used for calibrating lateral extensometers.

4. Two panels. Installed on a combined calibration rod: used for verifying simulated sheet metal specimens.

5 φ ten × 100 poles, 1 piece. Place it in the upper support arm clamp spring hole for simulating the calibration of samples with a diameter of more than 10mm.

6 φ ten × 50 rods and 1 piece. Placed in the connecting sleeve of the micrometer head for simulating the calibration of samples with a diameter of more than 10mm.

7 φ 10/ φ five × 1 piece of 100 reducing rod. Placed in the upper arm clamp spring hole for simulating the calibration of specimens with a diameter of less than 5mm.

8 φ 10/ φ five × 1 piece of 50 reducing rod. Placed in the upper arm clamp spring hole for simulating the calibration of specimens with a diameter of less than 5mm.

9. 1 170 mm extended column. Used to extend the height of the calibrator.

10. 1 connecting sleeve. Sliding measuring rod placed on differential measuring head φ On the 10 end, connect the separated sample for calibration.

11. For the convenience of debugging and installation, the instrument is equipped with one No. 14 solid wrench, one No. 3 Allen wrench, and one straight head and one cross head screwdriver each.

5、 Maintenance and upkeep

1. When disassembling the upper and lower support arms, it is necessary to prevent the positioning nails or steel balls from falling off. If the clamping jaws are too tight, only screws can be used to open them.

2. The precision of the differential head of the instrument has been calibrated when it leaves the factory, and it cannot be disassembled during use.

3. It should be used in a clean and dust-free environment, and attention should be paid to keeping the instrument clean and dust-free at all times.

4. Pay attention to preventing external damage and rusting.

5. Regularly submit to relevant metrology departments for re inspection.