Significant chemical and material composition improvements have provided an opportunity for the development of three gaskets, designed to address the regulations associated with asbestos substitute gaskets and fugitive emissions.

LineBacker® Zero, LineBacker® 250 and LineBacker® 251 gaskets are manufactured from new proprietary materials that provide excellent resistance against environmental leakage without the health hazards associated with asbestos type gaskets. In addition to providing zero environmental leakage, this new line of sealing gaskets:

Eliminate flange leaks.

Guard against blowouts.

Protect against hostile environments and fire.

Resolve asbestos substitution concerns.

Eliminate cold flow problems.

Reduce inventory costs.

Increase the overall life of the system.

Sizes: All standard ANSI and API flange sizes from 1/2” and above.
Shapes: Suitable for custom or odd sizes and shapes.
Pressure Ratings: All ANSI and API rated flanges. Pressures from hard vacuum to 50,000 psi and higher.

Solving Five Sealing Problems

The LineBacker Tackles Asbestos Substitute Problems.
The LineBacker seals better than either asbestos or asbestos substitute gaskets under most conditions. The LineBacker will maintain it’s sealing integrity from hard vacuum to pressures in excess of ANSI and API flange test ratings.

The LineBacker Tackles Flange Leaks and Blowouts.
The flange-to-retainer loading and retainer hoop strength, combined with the powerful pressure-energized feature of the LineBacker is powerful enough to prevent sudden catastrophic gasket failure.

The LineBacker Tackles Installation and Maintenance Costs.
A positive seal is effected first time, every time. Time spent in re-tightening or re-sealing flanges to compensate for gasket materials cold flow is also eliminated.

The LineBacker Tackles Inventory Costs.
The patented design of the LineBacker permits it to be used with ring joint, flat faced or raised face flanges; or with any combination of these flanges in a given size and pressure rating.

The LineBacker Tackles Flange Damage.
Near zero “m” and “y” factors make it possible to effect a positive seal without the tremendous bolt loads that are required with flat gaskets. Choosing retainer materials compatible with the flange materials will reduce potential corrosion problems. Also, the unique design prevents flange galling that can occur with chevron design gaskets.

Physical Properties

LineBacker® gaskets are available in a wide variety of retainer and sealing element combinations for matching gaskets to service and environmental conditions. This greater variety of materials also provides excellent temperature and chemical range compatibility.

Test Standard	Test Parameter	LineBacker Zero	LineBacker 250	Linebacker 251
ASTM D149	Dielectric Strength Volts/mil (Short Time)	500	500	550
ASTM D695	Compressive Strength	25,000 psi	50,000 psi	50,000 psi
ASTM D229	Water Absorption	1.8%	0.15%	0.15%
ASTM D790	Flexural Strength	20,500 psi	50,000 psi	50,000 psi
ASTM D785	Hardness	85	110	110
ASTM D256	IZOD Impact Strength	1.2 ft-lbs/in	11.5 ft-lbs/in	2.5 ft-lbs/in
ASTM D638	Tensile Strength	23,000 psi	40,000 psi	45,000 psi
ASTM D732	Shear Strength	10,000 psi	18,000 psi	20,000 psi
ASTM F-36	Compressibility	1.8%	2.0%	2.1%
ASTM F-36	Recovery	100.0%	88.9%	88.9%
ASTM F-38(B)	Creep Relaxation	65.7%	17.2%	5.1%
DIN-3535	Gas Permeability	0.00 cm3/min	0.29 cm3/min	0.43 cm3/min
DIN 52913	Stress Relaxation	N/A	49.4N/mm2	N/A
	Operating Temperature	-60 to +220ºF -51 to +104°C	-60 to +350°F -51 to +177°C	Cryogenic to +250° F (121°C)

Material	LineBacker Zero	Linebacker 250	LineBacker 252
Ammonia	R	R	R
Ammonium Hydroxide	F	F	R
Benzene	R	R	R
Butane	NT	NT	R
Calcium Hydroxide	U	U	R
Crude Oil	R	R	R
Dilute Acids	R	R	R
Ethanol
Gasoline	R	R	R
Hydrochloric Acid 20%	R	R	R
Hydrogen	NT	NT	R
Hydrogen Sulfide	NT	NT	R
Jet Fuel	R	R	R
Kerosene	R	R	R
Methanol	R	R	R
Naphtha	R	R	R
Natural Gas	R	R	R
Nitric Acid 10%	U	U	R
Nitric Acid 20%	U	U	F
Potable Water	NR	NR	R
Propane	R	R	R
Salt Brine	R	R	R
Sea Water	R	R	R
Sewage	R	R	R
Steam to 350ºF	U	R	U
Steam Condensate to 250ºF	U	R	F
Sulfuric Acid 10%	U	U	R
Toluene	F	F	R