VALQUATIGHT GASKET

Spiral Wound Gaskets use Non-Asbestos inorganic paper, VALQUAFOIL™ (expanded graphite) and VALFLON™ (PTFE) tape as filler materials, and exhibit good elasticity by means of a V-shaped hoop.

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VALQUA No.
8590TN
Product name
NONASUPER

Features1
NONASUPER are manufactured by winding metal strips (SUS304) around the periphery of basic 3.2 mm thick spiral wound gaskets.
Features2
NONASUPER can be used with the same level of tightening force as that of Compressed Fiber Sheet.
Features3
The maximum service temperature is 450 degrees Celsius.

Applicable fluids
Water, Sea water, Hot water, Steam,Crude oil, Alcohol, Animal & vegetable oil, Heat transfer oil,General solvent, Weak acid, Weak alkali,Air, Nitrogen gas, Inert gas,Exhaust gas,Inflammable gas,Extremely low temperature liquids,
Inappropriate fluid
Application
These are the best suited gaskets to be used for high temperature utility lines.
Materials of construction
Hoop material : SUS304 Filler material : Non-asbestos inorganic paper

■ Dimensions

Standard Flange

JIS 10K, JPI Class 150, 10A up to 200A〈Thicknes〉3.2mm

■ Construction of gasket

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Filler material: Inorganic paper

■ Available ranges

Temperature(℃) Pressure rating
-200〜450 JIS 10K

■ Design criteria

Recommended tightening stress
(MPa)
30.0

The recommended tightening stress are the pressures required under normal conditions, and correspond to the projected area of the gasket, where fluid pressure is not taken into consideration.

■ FAQ

Q. Is it possible to manufacture the spiral wound gasket in sizes other than the standard size?

A. Yes, it is possible for both the gasket main unit and inner & outer rings as long as you specify the size. However, please contact us because there is a range in which manufacturing is possible such as for the width.

Q. I want to control the width of the opening in the flange such as with a sheet gasket. How should I do this?

A. Control with width of the opening in the flange is prone to cause a margin of error and an accurate tightening stress cannot be obtained. It is effective for uneven tightening, so please use it in conjunction with control of tightening torque.

Q. Please tell me about the difference in the gasket dimensions between flanges of the JPI and ASME/ANSI standards.

A. JPI basically quotes from ASME/ANSI, so there are cases in which the dimensions differ slightly due to rounding error during the millimeter conversion of the original number. We understand that, in actual use, the function of the gasket is fulfilled to an equivalent degree by both dimensions.

Q. プWhy does leakage occur during stop or re-operation even though there are no problems during plant operation?

A. Expansion and contraction of the flange, bolt, pipe and the like will occur due to temperature changes. As a result, a tendency of reduced tightening force in the gasket main unit is often observed when the temperature decreases (including low temperature at the time of initial re-operation), and leakage occurs due to relaxation. We therefore generally recommend a retightening of the gasket before re-operation after the first heat addition.

Q. Is retightening effective when leakage occurs?

A. Yes, it is effective. We ask that retightening during leakage be performed after relieving internal pressure. However, there are also points to keep in mind for each product, such as the possibility of damage as a result of temperature-induced hardening in the case of a compressed non-asbestos fiber sheet.

Q. I am not sure which gasket to select, so could you select it for me?

A. If you contact us together with your operating conditions, we will recommend an appropriate product based on our technician's selection.

■ VALQUA HAND BOOK TECHNICAL DATA

■ VALQUA HAND BOOK DIMENSIONAL DATA


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