APM Hexseal’s Seeloc® Washers consist of molded silicone rubber bonded to specially formed stainless steel washers.

At APM Hexseal, we design and manufacture an expansive range of proprietary high-performance self-sealing hardware for use in environments ranging from standard to severe. Our product line includes bonded sealing washers, raised metal washers bonded with synthetic rubber to create a soft and durable sealing solution for fasteners. APM Hexseal has improved upon the bonded sealing washer design with our Seeloc® Washers.

 

 

IMPERIAL AND HEAVY DUTY SEELOC® WASHERS

IMPERIAL AND HEAVY DUTY SEELOC® WASHERS

Imperial SeelocWasher
MATERIAL SPECIFICATIONS

For APM Hexseal® Standard Seeloc® Washers

Elastomer:
Silicone† conforms to A-A-59588, Class 3A, GR50, Green ‡
Washer Material:
18/8 Stainless Steel
Temperature Range:
-103° F to +400° F ( -75° C to +204° C)
Pressure Range:
Up to 100 psig internal and external.
Resistant to:
Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
Shelf Life:
Excess of 25 years.
APM Hexseal
Part #
Compatible
Thread Size
Outer
Diameter (C)
Max. Mounting
Hole Diameter
75601#61/2" (0.550")1/4" (6.35mm)
75801#81/2" (0.550")1/4" (6.35mm)
75101#101/2" (0.550")1/4" (6.35mm)
75101HD#101/2" (0.550")1/4" (6.35mm)
75602#61"3/8" (9.53mm)
75602HD#61"3/8" (9.53mm)
75802#81"3/8" (9.53mm)
75102#101"3/8" (9.53mm)
75102HD#101"3/8" (9.53mm)
750821/4"1"3/8" (9.53mm)
75082HD1/4"1"3/8" (9.53mm)
751075/16"1"1/2" (12.70mm)
751223/8"1"5/8" (15.87mm)
75122HD3/8"1"5/8" (15.87mm)
751427/16"1"5/8" (15.87mm)
751621/2"1"5/8" (15.87mm)
75603#61-1/2"5/8" (15.87mm)
75803#81-1/2"5/8" (15.87mm)
75103#101-1/2"5/8" (15.87mm)
750831/4"1-1/2"5/8" (15.87mm)
751085/16"1-1/2"5/8" (15.87mm)
751233/8"1-1/2"3/4" (19.05mm)
751437/16"1-1/2"3/4" (19.05mm)
751631/2"1-1/2"3/4" (19.05mm)

† Alternative elastomers are available. Please consult our Molded Elastomer Options for details.
‡ Standard color for Metric Seeloc Washers is red. Alternative elastomer colors are available by special order.

METRIC SEELOC® WASHERS

METRIC SEELOC® WASHERS

Metric SeelocWasher
MATERIAL SPECIFICATIONS

For APM Hexseal® Standard Seeloc® Washers

Elastomer:
Silicone† conforms to A-A-59588, Class 3A, GR50, Green ‡
Washer Material:
18/8 Stainless Steel
Temperature Range:
-103° F to +400° F ( -75° C to +204° C)
Pressure Range:
Up to 100 psig internal and external.
Resistant to:
Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
Shelf Life:
Excess of 25 years.
APM Hexseal
Part #
Compatible
Thread Size
Outer
Diameter (C)
Max. Mounting
Hole Diameter
75031M314.0mm6.35mm
75041M414.0mm6.35mm
75051M514.0mm6.35mm
75032M325.4mm9.53mm
75042M425.4mm9.53mm
75052M525.4mm9.53mm
75062M625.4mm12.70mm
75312M825.4mm12.70mm
75392M1025.4mm15.87mm
75472M1225.4mm15.87mm
IMPERIAL AND HEAVY DUTY SEELOC® WASHERS

IMPERIAL AND HEAVY DUTY SEELOC® WASHERS

Imperial SeelocWasher
MATERIAL SPECIFICATIONS

For APM Hexseal® Standard Seeloc® Washers

Elastomer:
Silicone† conforms to A-A-59588, Class 3A, GR50, Green ‡
Washer Material:
18/8 Stainless Steel
Temperature Range:
-103° F to +400° F ( -75° C to +204° C)
Pressure Range:
Up to 100 psig internal and external.
Resistant to:
Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
Shelf Life:
Excess of 25 years.
APM Hexseal
Part #
Compatible
Thread Size
Outer
Diameter (C)
Max. Mounting
Hole Diameter
75601#61/2" (0.550")1/4" (6.35mm)
75801#81/2" (0.550")1/4" (6.35mm)
75101#101/2" (0.550")1/4" (6.35mm)
75101HD#101/2" (0.550")1/4" (6.35mm)
75602#61"3/8" (9.53mm)
75602HD#61"3/8" (9.53mm)
75802#81"3/8" (9.53mm)
75102#101"3/8" (9.53mm)
75102HD#101"3/8" (9.53mm)
750821/4"1"3/8" (9.53mm)
75082HD1/4"1"3/8" (9.53mm)
751075/16"1"1/2" (12.70mm)
751223/8"1"5/8" (15.87mm)
75122HD3/8"1"5/8" (15.87mm)
751427/16"1"5/8" (15.87mm)
751621/2"1"5/8" (15.87mm)
75603#61-1/2"5/8" (15.87mm)
75803#81-1/2"5/8" (15.87mm)
75103#101-1/2"5/8" (15.87mm)
750831/4"1-1/2"5/8" (15.87mm)
751085/16"1-1/2"5/8" (15.87mm)
751233/8"1-1/2"3/4" (19.05mm)
751437/16"1-1/2"3/4" (19.05mm)
751631/2"1-1/2"3/4" (19.05mm)

† Alternative elastomers are available. Please consult our Molded Elastomer Options for details.
‡ Standard color for Metric Seeloc Washers is red. Alternative elastomer colors are available by special order.

METRIC SEELOC® WASHERS

METRIC SEELOC® WASHERS

Metric SeelocWasher
MATERIAL SPECIFICATIONS

For APM Hexseal® Standard Seeloc® Washers

Elastomer:
Silicone† conforms to A-A-59588, Class 3A, GR50, Green ‡
Washer Material:
18/8 Stainless Steel
Temperature Range:
-103° F to +400° F ( -75° C to +204° C)
Pressure Range:
Up to 100 psig internal and external.
Resistant to:
Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
Shelf Life:
Excess of 25 years.
APM Hexseal
Part #
Compatible
Thread Size
Outer
Diameter (C)
Max. Mounting
Hole Diameter
75031M314.0mm6.35mm
75041M414.0mm6.35mm
75051M514.0mm6.35mm
75032M325.4mm9.53mm
75042M425.4mm9.53mm
75052M525.4mm9.53mm
75062M625.4mm12.70mm
75312M825.4mm12.70mm
75392M1025.4mm15.87mm
75472M1225.4mm15.87mm

What are Seeloc Washers?

Seeloc Washers work in combination with traditional bolts, screws, or studs to create an airtight seal around the fastener. The silicone contact surface features a continuous ridge that creates a 360° sealing barrier around the periphery of the washer face when compressed. The silicone rubber also forms a seal under the head of the associated fastener and makes full vertical contact with the threads/shank, making for a complete, high-pressure seal unlike any other.

Sealing hardware fastens disparate components together to prevent process fluids from escaping and external contaminants from entering. Proper seals ensure mechanical and electrical equipment continue to perform efficiently and effectively.

Types of Seeloc Washers APM Hexseal Offers:

Metric Seeloc Washers

APM Hexseal provides Seeloc Washers in all standard metric measurements, facilitating an easy selection process for manufacturers around the world. Our standard Seeloc metric washers are made from 18/8 stainless steel and feature a broad temperature range of -103°F (-75°C) to 400°F (204°C), internal and external pressure tolerances up to 100 psig, and a shelf life up to 25 years. They also resist dust, fungus, most acids and oils, splash, salt spray, sunlight, and ozone.

Imperial & Heavy Duty Seeloc Washers

APM Hexseal also offers Heavy Duty Seeloc® Washers, capable of handling torque values AT LEAST 50% higher than our original Seeloc Washers. Currently available in both 1/2” (14mm) and 1” (25.4mm) O.D. sizes, these new sealing washers are perfect for a myriad of sealing requirements, from medical equipment and chemical handling, to construction equipment and food processing. For information on maximum torque values for our Original and Heavy Duty Seeloc Washers please see our table of Torque Values for Seeloc® Washers.

Seeloc® Washers are a proven solution just waiting for a problem!

Bonded Sealing Washer Materials

Our Seeloc Washers are manufactured using stainless steel and molded using a variety of elastomers. Though silicone is the standard elastomer material for our Seeloc Washers, additional elastomer material options include EPDM, neoprene, and fluorosilicone. Our team will help you choose the best material for your needs.

  • Silicone offers superior heat resistance as one of its primary properties. High-temperature variations can withstand intermittent temperatures up to 500°F or continuous temperatures up to 437°F.
  • EPDM is a lower-cost material that offers excellent ozone, weather, and heat resistance. Sealing washers made from EPDM work well for outdoor applications.
  • Neoprene is a versatile facing material with resistances to chemicals, sunlight, ozone, weathering, and aging. Neoprene sealing washers perform well in a wide range of joint sealing applications.
  • Fluorosilicone combines the benefits of silicone and fluorocarbons, offering superior low temperature performance and high resistances to heat, flame, chemicals, weather, water, ozone, and more.

Seeloc Washers

Benefits of Bonded Sealing Washers

Bonded sealing washers provide superior performance over conventional sealing/fastening solutions in many ways. Some of the benefits offered by bonded sealing washers include: 

  • Better leak prevention. Bonded sealing washers eliminate the risk of premature loosening in response to vibration or noise, resulting in enhanced leak prevention.
  • Versatility. Various bonded sealing washer designs offer superior durability in extreme-temperature, high-torque, and otherwise demanding environments. Our Seeloc Washers are available in both imperial and metric measurements. 
  • Toughness. The strong elastomers used in bonded sealing washers resist tearing or shearing forces during tightening. Our Heavy Duty Seeloc Washers can handle at least 50% more torque than standard Seeloc Washers.

Gentleness. Bonded sealing washers offer an ideal solution to prevent fasteners from damaging delicate substrates.

Applications of Bonded Sealing Washers

Bonded sealing washers see broad use in a wide range of industries, including aerospace, agriculture, automotive, construction, marine, military, and mining.  In addition to conventional mounting holes, Seeloc Washers work with oversized holes and adjustment slots with non-standard shapes. They also work well for sealing knockout holes in electrical boxes and cabinets. The durability of Seeloc Washers ensures they can be removed and reused, making them well-suited to applications that require periodic maintenance or adjustments.

Equipment and systems that most commonly use bonded sealing washers include:

  • NEMA rated boxes and electrical enclosures
  • Hydraulics and braking systems
  • HVAC products
  • Industrial and construction equipment
  • Marine electronics

Quality

UL Recognized (UL Type 4X/6 enclosures) and IP66/68 rated, Seeloc Washers provide a high-performance, air- and liquid-tight seal that is ideal for applications where spray, vapors or wash-downs are present, or where there is a concern of damage from a wide range of contaminants, such as dust, oils and salt build-up.

APM Hexseal: Your Expert and Partner for Sealing Washer Needs

When you need reliable sealing hardware for critical equipment, turn to the experts at APM Hexseal. We’re an industry-leading supplier of quality sealing products for demanding industrial and commercial applications, including standard and heavy-duty bonded sealing washers.

With a reputation for continuous improvement, you can rely on us to develop and deliver innovative sealing hardware that address the challenges of your industry. To discuss your sealing requirements, Ask an Expert, or request a quote today.

Ever Better.