Month

Temperature

of Ambient, ˚C

Defined control standard of joints as to exposing time and MMF

Hot joint

Warm joint

Cold joint

Exposed

time, hrs

MMF,

H.˚C

Exposed time, hrs

MMF,

H.˚C

Exposed time, hrs

MMF,

H.˚C

1

22.8

≤16

557

16 - 28

556 - 974

>28

>974

2

22.5

≤16

552

16 - 28

552 - 966

>28

>966

3

22.1

≤16

546

16 - 28

546 - 955

>28

>955

4

20.9

≤20

658

20 - 30

658 - 987

>30

>987

5

18.5

≤22

671

22 - 32

671 - 976

>32

>976

6

16.5

≤22

627

22 - 32

627 - 912

>32

>912

7

16.4

≤22

625

22 - 32

625 - 909

>32

>909

8

18.9

≤22

680

22 - 32

680 - 989

>32

>989

9

22.5

≤20

690

20 - 30

690 - 1035

>30

>1035

10

24.9

≤16

590

16 - 28

590 - 1033

>28

>1033

11

24.4

≤16

582

16 - 28

582 - 1019

>28

>1019

12

23.2

≤16

563

16 - 28

563 - 986

>28

>986