The calculation formula for head size mainly includes cutting size, unfolded diameter, and wall thickness calculation.
one
Calculation formula for cutting size
Calculation formula for standard head cutting size:
D
=
one point two
D
N
+
two
h
+
S
D=1.2DN+2h+S
Among them,
D
D is the cutting size of the head,
D
N
DN is the nominal diameter of the head,
h
H is the height of the straight edge,
S
S is the thickness of the board.
Straight edge height
h
The value of h depends on the thickness of the plate
S
S varies differently: when
S
=
four
−
eight
When S=4-8,
h
=
twenty-five
h=25; When
S
=
ten
−
sixteen
When S=10-16,
h
=
forty
h=40; When
S
=
eighteen
−
thirty
When S=18-30,
h
=
fifty
h=50.
Non standard head cutting size calculation formula:
K
=
D
N
two
H
K=
2H
DN
D
one
=
D
N
+
S
D
one
=DN+S
A
=
(
K
two
+
one
)
one
/
two
A=(K
two
+1)
1/2
B
=
one
A
K
B=
AK
one
C
=
ln
(
A
+
K
)
C=ln(A+K)
Cutting size
D
=
D
one
(
one
+
B
C
)
one
/
two
+
two
h
D=D
one
(1+BC)
1/2
+2 hours.
Expand the diameter calculation formula
Unfolding diameter of stamped elliptical head:
D
i
×
one point two two three
+
one point five
h
+
twenty
m
m
Di × 1.223+1.5h+20mm margin.
Unfolding diameter of spinning head:
external diameter
×
one point one five
+
two
h
+
Correction amount
Outer diameter × 1.15+2h+correction amount.
Wall thickness calculation method
Hemispherical head: derived from thin film theory, the wall thickness can be calculated based on the inner or outer diameter of the container.
Elliptical head: Based on the cylindrical formula, the boundary effect at the connection between the head and the cylinder is determined by the shape factor
K
K reflects it. Ratio of major and minor axes
α
/
b
α/b should be controlled within 2.6, and the ratio of the major and minor axes of a standard elliptical head is 2,
K
=
one
K=1.
Dish shaped head: Multiply the calculation formula of the spherical part of the head by the shape coefficient
M
M corrected it. For
M
≤
one point three four
For disc-shaped heads with M ≤ 1.34, the effective thickness shall not be less than 0.15% Di; For
M
>
one point three four
M> The effective thickness of the 1.34 disc-shaped head shall not be less than 0.30% Di.