Technology

  1. Home
  2. Recommended Vibration Isolation Grade Table/Vibration Isolation Grade Diagram/Vibration Isolation Grade Chart

Recommended Vibration Isolation Grade Table/Vibration Isolation Grade Diagram/Vibration Isolation Grade Chart

1.Vibration isolation

The Vibration Isolation Grade estimates shown in Table 1 are determined based on the type of equipment installed

Table 1: Vibration Isolation Grade Table (estimated values)

Building structure Machine
installation
locations		 Allowable noise
from vibration
in rooms near
machinery rooms		 Installed
equipment
Reciprocating
freezers		 Screw-type
freezers		 Pumps Air
blowers		 Air
conditioners		 Cooling
towers
Less than
19kW		 19kW
or more		 Less than
60kW		 60kW
or more		 More than
2.2kW		 More than
15kW		 More than
19kW		 #2
More than
1/2		 #5
More than
1/2		 More than
#6		 Less than
10,000m
3/h		 10,000m
3/hor more		 Less than
100RT		 100RT
or more
Steel structure Intermediate
and top floors		 VL＜45
NC＜25		 Studio
VL＜50
NC＜35		 High-grade rooms
Reception room		 Ⅰ Ⅰ Ⅰ Ⅰ Ⅰ Ⅱ Ⅱ Ⅱ Ⅱ
VL＜55
NC＜40		 Conference room Ⅰ Ⅰ Ⅰ Ⅰ Ⅲ Ⅱ Ⅱ Ⅲ Ⅱ Ⅱ Ⅲ Ⅲ ※ Ⅱ
VL＜55
NC＜45		 Office
Dining hall
Lobby		 Ⅰ Ⅰ Ⅰ Ⅰ Ⅳ Ⅲ Ⅱ ※ Ⅲ Ⅱ Ⅲ Ⅲ ※ Ⅲ
VL＜60
NC＜50		 Parking lots ※ Ⅰ ※ Ⅰ ※ ※ Ⅲ ※ ※ Ⅲ ※ ※ ※ ※
Reinforced
concrete
construction		 VL＜45
NC＜25		 Studio
VL＜45
NC＜25		 High-grade rooms
Reception room		 Ⅰ Ⅰ Ⅰ Ⅰ Ⅰ Ⅰ Ⅰ Ⅰ Ⅱ Ⅱ Ⅱ Ⅱ
VL＜55
NC＜40		 Conference room Ⅰ Ⅰ Ⅰ Ⅰ Ⅲ Ⅱ Ⅱ Ⅲ Ⅱ Ⅱ Ⅲ Ⅲ ※ Ⅲ
VL＜55
NC＜45		 Office
Dining hall
Lobby		 ※ Ⅰ Ⅰ Ⅰ ※ Ⅲ Ⅱ ※ Ⅲ Ⅱ Ⅳ Ⅳ ※ ※
VL＜60
NC＜50		 Parking lots ※ Ⅱ ※ Ⅱ ※ ※ ※ ※ ※ Ⅲ ※ ※ ※ ※
Ground floors VL＜40
NC＜25		 Studio – –
VL＜55
NC＜45		 Office Ⅱ Ⅱ Ⅱ Ⅱ Ⅳ Ⅳ Ⅳ Ⅳ Ⅳ Ⅳ Ⅳ Ⅳ – –
VL＜60
NC＜50		 Parking lots ※ Ⅱ ※ Ⅱ ※ ※ ※ ※ ※ ※ ※ ※ – –

Notes
  • (1) I, II, III, and IV show the vibration isolation grade; * indicates that vibration-isolating equipment is not necessary.
  • (2) For blank fields, solid sound insulation is to be considered separately.
  • (3) VL indicates the vibration tolerance level (the dB level calculated by correcting the vibration acceleration level (VAL) to account for human sensitivity).

2.List of vibration isolation products

Table 3: Vibration Isolation Grade Table by Vibration-Isolating Materials

Installation type Vibration Isolation Grade Natural frequency (Hz)
Vibration Isolation Grade		 Product type Natural frequency range (Hz)
Product type
Placement type Ⅰ 1.9~3.0 Placement vibration-isolating spring TSSERIES:TS-3･TS-4/5 2.1~3.4
Ⅱ.Ⅲ 2.6~9.4 Multi vibration-isolating unit:TSU SERIES 4.3~5.0
Standard vibration-isolating frame:TSSERIES TS-1･TS-2 3.1~5.3
Ⅳ 7.1~14.4 Hybrid mat:TSM SERIES 7.3~9.0
High-performance rubber vibration isolator:Dimple Pad SERIES 8.9~15.0
Circular rubber vibration isolator:PTM SERIES 6.5~16.6
Oblong rubber vibration isolator:Ｒ SERIES 10.3~13.8
Ⅴ 12.5~25.6 Cushioning:Vibration-isolating pad SERIES 15.0~25.0
Hanger type Ⅲ 4.1~9.4 Spring vibration-isolating material:JS/JSH SERIES 4.9~5.9
Vibration Isolator spring Hanger:TSH SERIES 3.8~5.1
Ⅳ 7.1~14.4 Rubber Vibration Isolator Hanger:PTH SERIES(S) 8.6~17.4
Rubber Vibration Isolator Hanger:PTH SERIES(W) 6.1~12.3

The characteristics and Vibration Isolation Grade chart of representative vibration-isolating materials from Tables 1 and 3 are shown in Figure 1.

３.Vibration Isolation Grade

I, II, III, IV, and V shown in Figure 1 are the Vibration Isolation Grades in Table 3.

Vibration Isolation Grade

Vibration Isolation Grade、Vibration transmission rate

４.Vibration-isolating performance

The vibration transmission rates of the vibration isolation products shown in 2 are as follows.

(1) List of vibration transmission rates for placement-type products

Vibration-isolating performance

Equipment frequency
(rpm)		 Vibration transmission rateτ
Product models
TS-3 TS-1･TSU TSM DP
300 0.565 4.789 1.562 1.285
350 0.361 1.550 1.959 1.426
600 0.099 0.261 2.277 3.461
1000 0.034 0.081 0.334 0.696
2000 0.008 0.019 0.067 0.151
3000 0.004 0.008 0.029 0.080
Equipment frequency
(rpm)
Vibration-isolating performance ranking
Product models
TS-3 TS-1･TSU TSM DP
300 1 4 3 2
350 1 3 4 2
600 1 2 3 4
1000 1 2 3 4
1500 1 2 3 4
3000 1 2 3 4

:Vibration-isolating materials available for selection

The applicable product models based on the above vibration transmission rates are shown below

Equipment frequency
(rpm)		 Product models
TS-3 TS-1･TSU TSM DP
300 〇 ▲ ▲ ▲
350 〇 ▲ ▲ ▲
600 〇 〇 ▲ ▲
1000 〇 〇 〇 ▲
1500 〇 〇 〇 〇
3000 〇 〇 〇 〇


  • ○ :Applicable vibration-isolating materials
  • ▲ :Not applicable

(2)List of vibration transmission rates for hanger type products

防振性能について

Equipment frequency
(rpm)		 Vibration transmission rateτ
Product models
JSH･JS･TSH PTH(S) PTH(W)
500 0.425 1.818 2.684
750 0.153 2.437 0.833
1000 0.081 0.989 0.409
1500 0.034 0.362 0.192
Vibration-isolating performance ranking
Product models
JSH･JS･TSH PTH(S) PTH(W)
500 1 2 3
750 1 3 2
1000 1 3 2
1500 1 2 1

:Vibration-isolating materials available for selection

The applicable product models based on the above vibration transmission rates are shown below

Equipment frequency
(rpm)		 Product models
JSH･JS･TSH PTH(S) PTH(W)
500 〇 ▲ ▲
750 〇 ▲ 〇
1000 〇 〇 〇
1500 〇 〇 〇

  • ○ :Applicable vibration-isolating materials
  • ▲ :Not applicable

５.Sample reference documents for vibration isolating

Cross-section diagrams and plan diagrams for vibration isolating are shown below.
The below figure shows sample results of positional evaluations.

Sample reference documents for vibration isolating1
Sample reference documents for vibration isolating2

Vibration acceleration level1Vibration acceleration level1

List of evaluation results

Line type Number vibration-isolating materials VL value at evaluation point NC value at evaluation point
Product models
Number1.2.3.4:Floor-mounted vibration-isolating materials
Number5.6:Hanger type vibration-isolating materials、
Number7.8:mounted vibration-isolating materials+
Hanger type vibration-isolating materials		 Calculated VL value Determination Calculated NC value Determination
Calculated VL value≦
VL value at evaluation point of 55		 Calculated NC value≦
NC value at evaluation point of 40
1 Vibration-isolating spring 45 OK 15 OK
2 Multi unit（TSU） 45 OK 20 OK
3 Hybrid mat 45 OK 30 OK
4 Dimple Pad 45 OK 30 OK
5 Vibration-isolating spring materials
（JSH SERIES）		 45 OK 15 OK
6 Rubber Vibration Isolator Hanger
（PTH（single））		 45 OK 20 OK
7 Dimple Pad
/Vibration-isolating spring materials(JSH SERIES)		 45 OK 30 OK
8 Vibration-isolating spring materials(JSH SERIES)
/Rubber Vibration Isolator Hanger(PTH(single))		 45 OK 30 OK

As shown in the above position diagram, when outdoor units are installed on the roof and indoor units are installed on the reference floor,
and a typical office is at the evaluation point, the standard as shown at number 7 is Dimple Pads on the outdoor units and spring suspension vibration-isolating materials on the indoor units.


Categories