Grayloc® Clamp Connectors

Field-proven, compact, and lightweight alternative to conventional flanges.

Our trusted Clamp Connector design provides a simple-to-install solution that saves both space and weight across your operations. Delivering unparalleled design quality and reliability since the 1950s, our connectors feature metal-to-metal bore seal technology to meet your critical service piping and vessel connection requirements. The connectors’ light weight, smaller diameter, and shorter length support the design of optimized systems.

Metal To Metal Icon

Reduce installation time with quick and easy assembly

Eliminate Fugitive Emissions Icon 2 Edited

Eliminate fugitive emissions

Reduce Maintenance 1

Reduce maintenance costs and spare parts inventory

Grayloc® Clamp Connectors callout photo

Technical Specifications

Nominal pipe size½ to 64 in
Design pressure ratingFrom full vacuum up to 60,000 psig
Design temperature range-423 to 1700°F / -253 to 927°C


Hub Nickel alloys, carbon, low-alloy, stainless and duplex stainless steels
Seal ring Nickel alloys, low-alloy, stainless and duplex stainless steels
Bolting Nickel alloys, low-alloy, stainless and duplex stainless steels
Clamp Nickel alloys, carbon, low-alloy, stainless and duplex stainless steels

ASME B31.1, Power Piping
ASME B31.3, Process Piping
ASME B31.4, Pipeline Transportation Systems for Liquids and Slurries
ASME B31.8, Gas Transmission and Distribution Piping
ASME B31.12, Hydrogen Piping & Pipelines
ASME Section I
ASME Section VIII Div. 1
ASME Section VIII Div. 2
ASME Section VIII Div. 3
API 6A: Specification for Wellhead and Christmas Tree Equipment

Product Documents


Installation and Maintenance of the Grayloc® Connector | Letter

Grayloc® Ultimate Connector | Letter
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Product Variations

Typical Applications

Field Inspection and Maintenance Services

Grayloc offers on-site inspection and maintenance services to ensure the integrity of our connectors and to facilitate the return of worn or damaged hubs to within factory specifications.

Contact Us

Contact Us | Grayloc® Clamp Connectors

Company page Since our founding in the early 1960s, Oceaneering has expanded and grown globally to service several industries such as the offshore energy industry, defense, entertainment, material handling, aerospace, science, and renewable energy industries. In 1964, Mike Hughes and Johnny Johnson formed a Gulf of Mexico diving company called World Wide Divers. The company grew in response to increasing demand for their services and in 1969 merged with two other diving companies to form Oceaneering International, Inc. To solve the toughest challenges, we do things differently, creatively, and smarter. As your trusted partner, our unmatched experience and truly innovative portfolio of technologies and solutions give us the flexibility to adapt and evolve, regardless of market conditions. Our mission is to solve the unsolvable. We thrive by creating industry-changing technically creative solutions for the most complex operational challenges under water, on land, and in space. Our five core values establish a common culture and demonstrate what is most important for us as a company. Since the beginning, the company has transformed from a small regional diving company into a global provider of engineered products and services. Today, we develop products and services for use throughout the lifecycle of an offshore oilfield, from drilling to decommissioning. We operate the world's premier fleet of work class ROVs. Additionally, we are a leader in offshore oilfield maintenance services, umbilicals, subsea hardware, and tooling. We also serve the aerospace, defense, and theme park industries. Underpinning everything we do, safety is not only the foundation of our core values, but it is vital to our unmatched performance record and company culture. The industries we serve are as diverse as they are complex. Whether we are engineering deepwater umbilicals or developing robotics for aerospace applications, the safety and health of our employees, vendors, and customers is an integral part of our day-to-day business. If we are working, then our responsibility is to be working safely. Since our inception in 1964, we have placed a high value on employee safety—from diving services and subsea inspection to vessel-based installation operations. We have and will continue to evolve not only our health, safety, and environmental (HSE) processes, but those of the industries in which we work. Although we have been fatality-free since 1999, our HSE journey goes beyond statistics. As our portfolio of services has grown, we have continued to prioritize and advance our approach to HSE.