Spiral wound gaskets
files/45/en/DIMER_Industrial_gasket_Spiral_wound_gasket.jpg

DIMERFLEX ST - Spiral wound gaskets produced by DIMER are particularly suitable for pressure-fluctuating and loaded flange joints in a wide temperature range. They can be applied to pressures up to 250 bar (even more) and they are resistant to high temperatures up to 1100 °C.

They are produced in a variety of basic material combinations with/without an external or an inner metal ring, or in atypical dimensions or shapes according to customer specifications.
Standard sizes according to EN, DIN, ASTM and BS standards, non-standard shapes are also available (ellipse, oval).

On request we can produce DIMERFLEX ST in "soft design" (low stress), using a sealing filler in quality to be used in applications in nuclear power plants, or including internal bars of various shapes according to customer requests / supplied drawings.

In case of leaks and the impossibility to seal up the flange joint using RTJ we can offer a solution by means of the VCS system (ATYP/ASME/ANSI B16.5)

Construction of Spiral wound gasket

1-outer / centering metal ring
2-inner metal ring
3-filler / sealing element / V shaped
4-metal strip / V shaped
  4a-outer free metal winding
  4b-inner free metal winding

files/45/en/SWG-rez21.jpg

Standard profiles

DIMERFLEX ST10

without outer and inner rings

DIMERFLEX ST20

with inner ring only

DIMERFLEX ST30

with outer ring only

DIMERFLEX ST40

with outer and inner rings

DIMERFLEX ST10Z

with special PTFE sealing zone

Thickness of gaskets

t1 (mm) tolerance t1 (mm) diam.d3 (mm) bmax (mm) t2 (mm) thickness after fitting (mm)
7,2 +0,35 100 - 3200 33 5,0 5,3 - 5,6
6,4 +0,3 100 - 1600 30 4,0 4,7 - 4,9
1601 - 3200 25
standard 4,5 +0,3 15 - 630 35 3,0 3,2 - 3,4
631 - 1600 30
1601 - 2000 20
3,5 +0,25 15 - 1000 25 2,0 2,3 - 2,5
3,2 20
2,5 +0,25 15 - 500 10 1,5 1,8 - 2,0

Standard metal materials

material AISI / ASTM spec. acc.to EN 10027-1 material acc.to EN 10027-2 BS ČSN /CZ temperature (°C) hardness (HB)
min max
carbon steel 238-C RSt. 37.2 CS 1.0038 D/40B 11 375 -40 +500 100-120
low carbon steel - M2 / ARMCO 1.1003 S/LCS - -60 +500 90-110
stainless steel 304 X5CrNi 18 10 1.4301 304S 15/16/31 17 240 -250 +550 130-180
stainless steel 304L X2CrNi 19 11 1.4306 304 S11 17 249 -270 +550 130-170
stainless steel 309 X15CrNiSi 20 12 1.4828 309 S24 17 251 -110 +1000 130-220
stainless steel 316 X5CrNiMo 17 12 2 1.4401 316 S31/33 17 346 -200 +550 130-190
stainless steel 316L X2CrNiMo 18 14 3 1.4404 316 S11/13 17 349 -200 +550 120-170
stainless steel 316Ti X6CrNiMoTi 17 12 2 1.4571 320 S31 17 348 -270 +550 130-190
stainless steel 321 X6CrNiTi 18 10 1.4541 321 S12/49/87 17 247 -270 +550 130-190

STANDARD FILLERS

sealing element temperature (°C) pH application colour coding
min. max.
FG (expanded graphite) -200 +550 0-14 aggressive medium grey
PTFE (polytetrafluorethylen) -200 +260 0-14 aggressive medium white
CER (ceramic) -200 +1100 - very high temperature light green
MIC (mica) -200 +1000 - high temperature pink

Table of recommended seating stress

sealing element seating stress for DIMERFLEX ST40 (MPa at +20°C) seating stress for DIMERFLEX ST30
(MPa at+20°C)
min. recommended max. min. recommended max.
FG (expanded graphite) 50 125 300 50 90 180
PTFE (polytetrafluorethylen) 50 110 250 50 80 130
CER (ceramica) 60 120 150 60 90 150
MIC (mica) 70 100 160 70 95 160

Table of recommended flange surface finish

roughness value (µm) application
Ra - 3,2 6,3 12,5 - recommended
Ra 1,6 - - - 25 acceptable under specific conditions
Files to download
DIMERFLEX ST-SWG



  • Industrial gaskets
  • Gasket materials
  • Dynamic packings
  • Mechanical seals
  • Hydraulic and pneumatic systems
  • Other products
  • Počet přístupů: [507049] ©2001-2020 Dimer, spol. s r. o.