1. Transmission programme
JOYRO
Transmission programme
JOYRO Pulleys
Flexible couplings
TB pulleys (solid)

2. Agenda • History & Facts • Range & sizes • Pulley programme • Function
• Term
• Taper Bush
• REC V – Belts
• Dimensions / tolerances
• Catalogue – JOYRO Pulleys
Advantages
• Weight reduction
• Design
• Startup Energy
• Small Tension
• Increased speed
• Reduced belt temperature
• Balancing
• Samples
• Features of the JOYRO Pulley

3. History - facts History : 2007 JOYRO Pulley design.
Prototypes and load tests.
First JOYRO Pulley on the market.
Additional tests : Temperature, wear, noise …etc.
Produced by Joy and Happiness ., LTD.
Today :
• Main applications :
• Compressors,
• Ventilating plants / Air conditioning,
• Paper mills,
• Agriculture…etc.
• Main Customers :
Samsung Electronics, Samsung Techwin, LG Chemical, LG Display,
LG Electronics, SKC, Hyundai Motor Group, Kia Motor Group,
…etc.

4. Range & sizes JOYRO® Pulley SG Iron FCD 500
SPZ, SPA, SPB, SPC - Diam mm
Traditional Pulley
Grey Iron FC 25
SPZ, SPA, SPB, SPC - Diam mm

5. Pulley programme
Grooves
Rim
Arms/spokes
Hub
Shaft
Bush
Screws

6. Function
Terms
ISO 4183

7. Taper Bush
Taper Bushes >>

8. REC Type V-belts
JOYRO Pulley

9. Dimensions/tolerances

10. Catalogue - Pulleys

11. Advantages

12. Weight reduction Weight reduction 40-50 % Table 1 Pulleys reduced
from more than 40kg
to less than 40kg
Table 1

13. Design
Example
Traditional SPB / JOYRO SPB 450-8

14. Startup energy
Traditional SPB *8
JOYRO SPB *8

15. Smaller tension in arms
Because of the tangential
connection between arms and
hub the tensile stress in the
arms will be reduced as the
hub is able to rotate fractions
of degrees during the cooling
period after casting.

16. Increased speed double speed is double power!! Increased speed (test)
Setup:
5 kW motor (n1 = 3000 rpm)
Frequency changer
SPA 200-2, SPA 100-2
SPB 355-4
The SPB mountet as shown
with no belts, and the rotational
speed n2 is increased to 7400 min
-1 ~138 m/s.
No damage on pulley, and further
tests were not found expedient.
d3 = SPB 355-4
d1 = SPA 200-2
D2 = SPA 100-2

17. Reduced belt temperature
Thermal imaging camera shooting
Traditional SPB 250-4
(After 2 working hours)
JOYRO SPB 250-4
(After 2 working hours)

18. Correlation between the belt and the temperature
Every 10°C reduced belt temperature =Double life length!!

19. Balancing Standard balancing grade (ISO 1940) : G16 (30m/s)
Static / Dynamic balancing (ISO 254) :
1,58 x 1011
Dm x B
n =
v x 60
Dm x 10 x -3
n =
n < n : Static balancing 1
n > n : Dynamic balancing
Special demands regarding balancing
can be arranged!

20. Transferring high power at high revolutions
(Compressor customer)
Alt.: 1
Transmission with regular v-belt pulleys
n1 = 1500 min-1
P1 = 200kw
d1 = SPB 450-8
Required output: P = 200 kw , nw = 8000 min-1,
Solution:
n1 = 1500 min-1
d1 = 450 mm
nw = 8000 min-1
pw = 200kw
n2 = nw/4 = 2000 min-1 (Gearbox)
n1 = d2/d1 x 2000 min-1
d2 = n1/n2 xd1 = 335 mm
Belt speed:
V = d1 x n1 x p /60
= 0,45 x 1500 x p/60 = 35 m/s
n2 = 2000 min-1
d2 = SPB 335-8
Gearbox
required!

21. Transferring high power at high revolutions
(Compressor customer)
Alt.: 2
Transmission with VTP/SG Iron pulleys
n1 = 3000 min-1
P1 = 200kw
d1 = SPA
P = 200 kw , nw = 8000 min-1,
P1 = 200 kw , n1 = 3000 min-1, d1 = 0,45 m
dw = n1/nw x d1 = 170 mm
nw = 8000 min-1
pw = 200kw
Belt speed:
V = d1 x n1 x p /60
= 0,45 x 3000 x p/60 = 70 m/s
n2 = 8000 min-1
d2 = SPA
Gearbox
eliminated!!

22. Features of the JOYRO Pulley