Spring dial scales calibration

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Major Contents

  1. What are spring dial scales?
  2. Structure and operating principle
  3. Application
  4. Why should you calibrate spring dial scales?
  5. Calibration procedure

 

Spring scales are a popular type of watch scale widely used in daily life. With its convenience and fairness, spring scales ensure that measuring becomes easier and more accurate. The spring scale calibration process is also simple, helping users trust in the accuracy of the measurement results.


1. What are spring dial scales?
 

Spring scales (also known as spring dial scales) are a popular type of scales widely used in everyday life. Due to its convenience and much cheaper price compared to electronic scales, it is a common choice for many people.

Spring scales come in two types: tabletop and hanging, usually with accuracy class IIII and the ability to weigh up to 200kg (according to OIML R76-2006)

 

 

2. Structure and operating principle

 

 

 

 

 

2.1 Structure

The spring scale is designed based on the principle of the spring and the principle of balance. The structure of the spring scale includes the following main components: spring, rack, pinion, spring frame, pointer, dial with number markings, protective cover, weighing plate or hanging hook.

The spring scale operates on the principle of elasticity of the spring, creating a state of balance when the spring is compressed (tabletop spring scale) or stretched (hanging spring scale).

 

2.1 Operating principle

 

The spring scale operates on the principle of Hooke's law, which states that "the force required to extend or compress a spring is directly proportional to the force applied to it". This principle is used to measure the mass or force acting on the spring.

Here is how a spring scale works: The rack and pinion mechanism converts the linear motion (compression or extension) of the spring into circular motion, combined with the pointer and dial to indicate the measurement result. In addition, there is a rotating knob on the top of the dial, which adjusts the zero point when there is no load.

Based on these principles, spring scales have become popular tools for calculating and measuring mass and force in various fields, from business to manufacturing and health.

 


3. Application
 

- Spring watch scales are a popular measuring device used in everyday life. Here are some applications of spring scales in life:

  • Measure the weight of small objects such as food, jewelry, coins, etc.
  • Used in testing tensile and compressive forces of industrial components such as construction, automobile manufacturing, machinery, parts such as springs, gear tubes, etc.
  • Used in balance testers and indicators as pressure gauges.
  • In the manufacturing industry, spring scales are used to measure the destructive force of materials, helping in the process of checking product quality.
  • Spring scales are used in the quality industry to help measure the load-bearing capacity of equipment and materials.
  • In medicine, spring scales are used to measure the amount of powder or liquid medicine needed to treat a patient.

- Therefore, it can be said that a spring scale is one of the versatile measuring tools, having many applications in daily life as well as in industry and medicine.

 


4. Why should you calibrate a spring dial scale?

Over time, the accuracy of measuring devices gradually decreases, and watch scales are no exception. Periodic calibration helps ensure the reliability of measurement results and promptly detect unusual deviations or failures.

 


5. Calibration procedure

5.1 Calibration means

Accuracy level of weights used for calibration: M1 precision weight set or higher accuracy level.

5.2 Calibration conditions

- When performing calibration, the following conditions must be met:

  • Standard weight: The total nominal mass of the standard weight is at least equal to the Max of the scale.
  • Temperature: as the normal working temperature of the scale according to the manufacturer's regulations
  • The influence of external influences (vibration, vibration, wind,...) does not distort the results
  • The scale should be calibrated at the site of use.
 
5.3 Prepare calibration
 

- The scale must be completely assembled, cleaned, and adjusted for balance. If the scale has a Nivo, the water bubble must be adjusted to the midpoint of the centering line, ready for calibration.

- Gather enough standard weights, specialized test racks, and auxiliary optical disks.

- Temperature stability for precision cable weights E2, F1 and F2 according to the requirements in Table 3 of the technical documents

5.4 Perform calibration
 
 
5.4.1 Initial inspection
 

- Check the label, name of manufacturer (country), weight, Max, Min, and graduation value;
- The scale must have all necessary details, parts, and accessories
- The indicator must be clear and read accurately

 

5.4.2 Technical inspection
 
- Technical inspection according to the following requirements:
  • The weight-receiving part of the scale must be sturdy, firmly installed and not entangled by other parts of the scale
  • The watch hands do not touch the glass and dial throughout the entire working range (from "0" to Max).
  • If you detect an error in the needle's index at point 0, proceed to return the scale's index to "0".
 
5.4.3 Measurement inspection
 
- Check angular deviation
- Check repeatability
- Check accuracy
 
5.4.4 Estimate the measurement uncertainty
 

Measurement uncertainty (MU)  is compiled from the following sources:
- MU of standard weights
- MU due to resolution at load level
- MU due to repeatability
- MU due to angular deviation

 
5.5 General handling

- After calibration, the spring dial scale is stamped and issued a calibration certificate with the calibration results.
- Recommended calibration cycle: 01 year


To consult and request a quote on our calibration services, please kindly contact us via the following information:

LABORATORY: DONG TAM MEASUREMENT AND TECHNICAL TRADING SERVICE CO., LTD

Address: No.57-59 Street 11, Binh Hung Residential Area, Binh Hung Commune, Binh Chanh District, Ho Chi Minh City

TEL: 028 375 83 869 - Hotline: 0909 347 891 (Mr. Lâm)

Email: info@dongtam-mes.vn