Specifications for Cement Mortar Cube Vibrating Machine, IS: 10080 (1982)

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Dear readers, this blog post covers specifications for cement mortar cube vibrating machine according to the standard IS: 10080 (1982). Parts of vibration machine and it's construction also discussed here.

Specifications for Cement Mortar Cube Vibrating Machine, IS 10080 (1982)


Table of Contents   (toc)

Here you will be learn about requirements of vibration machine used in casting of 70.6 mm sized cement mortar cubes in the test for determination of compressive strength of hydraulic cement.


Mortar Cube Vibrating Machine: Definition

Mortar cube vibrating machine is used for the preparation and compaction of 70.6 mm sized mortar cube specimens in compressive strength test of cement.

Mortar Cube Vibrating Machine

Materials of Construction of Different Components of Vibration Machine


Sl. No. Parts Material
1. Bed ISLC 200
2. Vibrator Cast Iron
3. Eccentric shaft Mild Steel
4. Pulley Mild Steel
5. Support spring Spring Steel
6. Tension spring Spring Steel
7. Hopper Brass
8. Drive pulley Cast Iron
9. Belt Cotton/Nylon
10. Motor
11. Motor support plate Mild Steel
12. Mould Cast Iron/Mild Steel


Construction of Mortar Cube Vibrating Machine

Vibration machine shall be constructed generally as shown in below figure and shall consist of a vibrator, housing revolving shaft with eccentric supported on four springs, which assembly is mounted over a bed of channel. A motor (3/4 hp, 2800 rpm) carrying a pulley shall be coupled to the vibrator revolving shaft through an endless belt. A belt guard shall be provided. The machine may be fitted with time switch.

Mortar Cube Vibrating Machine
Fig. 1: Construction of Vibration Machine

The vibrator shall be constructed to comply with the following essential requirements:
Mass of vibrator on its supporting springs (excluding solid eccentric and cube hut, including mass of mould, mould clamp and hopper) 29±0.5 kg
Out of balance moment of eccentric shaft 0.0016 kgm
Normal running speed of eccentric shaft 12000±400 rpm

The centre of gravity of the vibrator, including the cube and the mould, shall be either to the centre of the eccentric shaft or within a distance 25 mm below it. For this purpose, a mild steel plate may be fixed to the vibrator.


Parts of Vibration Machine

1. Bed

The bed of the vibration machine shall be made of steel channel and shall be provided with four cast iron feet. It shall be provided with four levelling bolts. Four support springs shall be fitted for positioning the coiled springs. A bracket shall be provided for fixing one end of a tension spring.

2. Vibrator

  1. The vibrator shall be mounted over four coiled springs.
  2. The vibrator platform shall be provided with two guide pieces for positioning a cast iron mould clamp which carries a cube mould of size 70.6 mm.
  3. A suitable arrangement for mounting a hopper shall be provided and a tension spring shall be fitted as shown in above Fig. 1.
  4. A brass hopper fitted on to a mild steel frame with projecting lugs shall be positioned over the mould as shown in Fig. 1.
  5. The vibrator shall house a revolving shaft with an accurately machined eccentric. A pulley shall be fitted to the shaft.

3. Springs

The springs shall be as shown in Fig. I. The stiffness of the spring shall be such that the natural frequency of the machine mounted on it is well below its minimum running speed.

4. Drive

The drive should be by an endless belt running on a pulley on the motor and a pulley on the vibrator.

5. Mould

The mould shall be of 70.6 mm size and shall be constructed generally in accordance with table given below. The dimensions of the mould with tolerances shall be as specified in Table.

Dimensions and Tolerance of Mould

Sl. No. Discription Dimensions
1. Distance between opposite faces, mm 70.6±0.1
2. Height of mould, mm 70.6±0.1
3. Thickness of wall plate, mm 12
4. Angle between adjacent interior faces and between interior faces and top and bottom planes of mould 90±0.5°
5. Length of base plate, mm 97
6. Width of base plate, mm 97
7. Thickness of base plate, mm 6
8. Permissible variation in the planeness of interior faces, mm
for new moulds
for moulds in use

0.03
0.05
9. Permissible variation in the planeness of base 0.15

The cube mould shall be constructed in such a manner as to facilitate separation into two parts. The mass of the mould together with the base plate shall be 2.8 ±0.2 kg. Other requirements of the mould shal1 be as laid down in IS: 10086-1982.

FAQs

What is mortar cube vibrating machine?

Mortar cube vibrating machine is used for the preparation and compaction of 70.6 mm sized mortar cube specimens in compressive strength test of cement.

What is the use of mortar cube vibrating machine?

Mortar Cube Vibrating Machine is used for vibrating the mix in moulds at a frequency of 12,000 Â ± 400 cycles per minute. The vibrator is mounted over 4 coiled springs and the vibrations are developed by means of a revolving eccentric shaft.

Is code for cement vibrating machine?

IS: 10080-1982. Specifications for Cement Mortar Cube Vibrating Machine.

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