FAQ

What does the marking on a spiral wound gasket refer to?

Standard spiral wound gaskets are manufactured per ASME B16.20 to suit ASME B16.5 flanges.

The markings should include the following:

  • LAMONS (Manufacturer)
  • Nominal pipe size
  • Pressure class
  • Winding metal abbreviation: 304SS may be omitted
  • Filler material abbreviation
  • Guide ring and inner ring material abbreviations: 304SS may be omitted when it is used for an inner ring and carbon steel may be omitted when it is used as a guide ring
  • ASME B16.20 designation

What are color codes for spiral wound gaskets per ASME B16.20?
  • View color coding chart (PDF)
  • The metallic winding is designated by a solid color around the guide ring
  • The filler material is designated by stripes equally spaced around the guide ring
  • Example:
    • The yellow color: 304 SS winding metal
    • The Gray stripe: FG filler

What is the purpose of an inner ring in a spiral wound gasket?
There are many advantages to using an inner ring:
  • Provides additional compression stop
  • Provides additional blowout resistance
  • Prevents build up of process fluid
  • Minimizes erosion and turbulence
  • Shields the gasket
  • Prevents buckling
  • Promotes tightness
What are some causes of inward buckling?
  • Over-compression
  • Smooth surface finish
  • Grease on the flange or on the gasket
  • Uneven loading
  • Bolt up inconsistencies
  • Pinching the gasket during installation
  • Extreme temperatures
  • Improperly sized / Wrong dimensions
  • "Slippery" filler materials
  • Less compressible filler materials
What are the temperature limits for spiral wound gaskets?
The limits are generally dependent on the filler material:
Standard graphite: 850°F
Super inhibited graphite: 975°F
PTFE: 450°F

View spiral wound literature (PDF)
What type of gasket is used for high temperature applications?
Lamons HTG configuration (High Temperature Gasket) is rated to 1500°F can be applied to different gasket styles such as:
  • Spiral wound
  • Kammpro
View the HTG literature (PDF)
What type of gasket is suggested for use in severe corrosive environments, such as in a Hydrofluoric Acid (HF) unit?
WRI-LP: spiral wound gasket with a special Kammpro inner ring can provide complete sealing.

View Flyer
Is there a low compression spiral wound gasket?
WRI-LC: this gasket design reduces the Y value (minimum design seating stress) from 10,000 PSI to 5,000 PSI

View Flyer
What is the suggested flange surface finish for spiral wound and Kammpro gaskets?
125-250 AARH
What are the M and Y values for Kammpro, CMG, CMGT, CMGPTFE, Spiral Wound Gaskets (W, WR, WRI), and WRI-LC?
Gasket Style M-value Y-value (PSI)
Kammpro
2.75
3,700
CMG
2.75
3,700
CMGT
2.75
3,700
CMG-PTFE
2.75
2,500
Spiral wound
3
10,000
WRI-LC
3
5,000
What is the yield strength for B7 bolts?
105 KSI
How can torque value be calculated?

T = (S * D * A * R) / 12

Where:

  • T: torque value (ft-lb)
  • S: required bolt stress (PSI)
  • D: bolt diameter (in)
  • A: area at root of thread (square inches)
  • R: friction factor
Is there a gasket solution for adapting a raised face flange with a ring joint type flange?

WR-RJ and WRI-RJ

WR-RJ: a spiral wound gasket with guide ring and sized properly to suit a raised face flange and a ring joint flange.

WRI-RJ: a spiral wound gasket with guide and inner ring, for non-standard bore. A pipe schedule is required to size the inner ring properly.

Kammpro Adapter: this design has the advantage of kammprofiled on the sealing areas faced with soft material such as graphite, depending on operating conditions. There are some sizes that are not suitable, so please check with Lamons Engineering Department regarding this design.

How do you install a gasket?
We will include a link that would open the procedure.
What type of gasket is suggested for use in severe corrosive environments, such as in a Hydrofluoric Acid (HF) unit?
WRI-LP: spiral wound gasket with a special Kammpro inner ring can provide complete sealing.

View Flyer
What are suggested pressure classes for CMG gaskest?
CMG gaskets are suggested to be used only in 150 and 300 pressure classes. For higher pressure classes, Kammpro gaskets are preferred.
What are typical torque values for ring joint gaskets?
Typically 50% of the bolt yield is applied as a bolt stress. API 6A includes a torque table for its flanges.
What are common metal material temperature limits?

Note: The maximum temperature ratings below are based upon hot air constant temperatures. The presence of contaminating fluids and cyclic conditions may drastically affect the maximum temperature range.

 Maximum Temperature
Material
°C
°F
Carbon Steel
538
1000
304 SS
760
1400
309 SS
1095
2000
310 SS
1150
2100
316 SS
760
1400
321 SS
815
1500
347 SS
925
1700
410 SS
705
1300
430 SS
815
1500
501 SS
649
1200
Alloy 20
815
1500
Aluminum
427
800
Brass
260
500
Copper
260
500
Hastelloy B & C
1095
2000
Inconel 600
1095
2000
Incolloy 800
871
1600
Monel
815
1500
Nickel
760
1400
Phosphor Bronze
260
500
Tantalum
1649
3000
Titanium
1095
2000
What do the markings on a Ring Joint gasket stand for?

  • 6A0112.1 = API License Number (Specific to Lamons)
  • RX 39 = Part Number. Specific to each style and size gasket
  • S-4 = Material Code and Product Specification Level S Represents Steel, this code is specific to each material. The "-4" represents the product specification level, with "4" being the highest level.
  • 08-06 = Date of Manufacture (August 2006. i.e.)
  • 212380 = Heat Number, specific to each gasket and can be used to trace the gasket back to its raw material
What is a "fire safe" gasket??
A gasket which typically passes a stringent test, such as API 6FB is considered "fire safe". Lamons produced several designs which have passed tests shuch as this.

Contact Engineering for more information.

What is a typical substitute for Asbestos filler material in a spiral wound gasket?
Graphite can be used as a substitute for Asbestos material in numerous applications.
What is the suggested filler material if a mica/graphite mix was previously used?
Flexible graphite would be preferred since it has better sealing ability, temperature and chemical resistance.
What information is typically requested to provide gasket suggestions?
  • Flange details (which includes the sealing area and bolting information)
  • Operating temperature
  • Operating pressure
  • Process media
How can we contact the technical department at Lamons?
Send an e-mail to engineering@lamons.com
When can I use oval and octagonal cross section ring joint gaskets?
  • Oval: can be used in the old type round bottom groove or the new flat bottom groove
  • Octagonal: can be used only in the flat bottom groove

The octagonal cross section has higher sealing efficiency than the oval and it would be the preferred design.

What is the most important physical charateristic in ring joint gasket metal material?
The most important factor is to have the ring gasket material softer than the flange material to prevent deforming the flange
What is a typical upgrade design to be applied in a heat exchanger?
The Kammpro gasket design is a preferred design when needing improved performance at low seating stresses.
What is a general temperature rating for compressed non-asbestos sheet material?
Typically it is rated to 400°F
What is the recommended compressed thickness for spiral wound gaskets?
Gasket Thickness
Suggested Compressed Thickness
0.0625”
0.050/0.055”
0.100”
0.075/0.080”
0.125”
0.090/0.100”
0.175”
0.125/0.135”
0.250”
0.180/0.200”
0.285”
0.200/0.220”
What are typical Style W gasket dimensions when it is confined on the OD and ID?
  • Gasket ID = Groove ID + 1/16”
  • Gasket OD = Groove OD – 1/16”
What are typical Style W gasket dimensions when it is confined on the OD only?
  • Gasket ID = Bore + Minimum 1/4”
  • Gasket OD = Recess OD – 1/16”
Which spiral wound specification is applied when DN/PN is given?
Typically EN 1514-2 dimensions are used for metric flanges unless otherwise specified
Can Lamons manufacture a convex root profile Kammpro gasket?
Absolutely
Can Lamons provide Kammpro gaskets thicker than 5/32”?
In some cases, we have manufactured Kammpor well above this thickness.