Gruvlok Grooved Fittings

Gruvlok fittings are grooved mechanical pipe fittings, couplings, flanges, and flow control components designed for fast, bolt-together pipe system assembly without welding or soldering. The Gruvlok product line from Anvil International includes grooved couplings, 90-degree and 45-degree elbows, tees, reducers, caps, branch clamps, and flanges, with fittings available through 24" nominal pipe size per Gruvlok product documentation. The Figure 7001 Gruvlok flexible coupling is rated to 1,000 PSI working pressure and is the standard grooved connection for mechanical, plumbing, process piping, and HVAC hydronic applications. Gruvlok fittings require pipe ends grooved to Gruvlok specifications and the correct gasket material for the service fluid and temperature, making gasket selection the primary technical decision when specifying grooved connections.

Figure 7001 Standard Flexible Grooved Couplings

The Gruvlok Figure 7001 is the standard flexible grooved coupling, rated to 1,000 PSI working pressure without excessive casting weight, per Gruvlok product documentation on SupplyHouse. The 7001 coupling forms a flexible grooved end pipe joint that reduces pipeline noise and vibration transmission without additional components. Available with EPDM gaskets for water, glycol, and most HVAC applications, and with nitrile gaskets for petroleum, oil-vapor, and mineral oil applications. Nitrile gaskets are not for use in hot water or hot air service; EPDM gaskets are not for petroleum applications. The 7001 is available in sizes from 1" through larger commercial pipe sizes on SupplyHouse.

Figure 7401 Rigidlok Couplings

The Gruvlok Figure 7401 Rigidlok coupling is a rigid grooved pipe connection designed for applications requiring a rigid joint rather than the flexible movement allowed by the 7001 coupling. The 7401 Rigidlok uses a housing design that conforms to and grips the pipe, with the Guidelok feature automatically separating pipe ends and guiding the coupling into the grooves as bolts are tightened. The 7401 is designed for use with roll-grooved or cut-grooved standard weight pipe, lightweight roll-grooved pipe, and grooved-end fittings. Installation requires removing only one nut and swinging the housing over the gasket, making single-technician installation feasible on larger pipe sizes.

Grooved Fittings (Elbows, Tees, Reducers, Caps)

Gruvlok grooved fittings include 90-degree and 45-degree elbows, standard and reducing tees, concentric reducers, and caps in sizes through 24" nominal pipe size. Pressure ratings of Gruvlok standard fittings conform to those of the Figure 7001 coupling per Gruvlok engineering documentation. Fittings are designed for minimum pressure drop and uniform strength throughout. Concentric reducers (47 configurations on SupplyHouse) allow pipe size transitions within a grooved system without welded or threaded reducing fittings. All fittings require grooved pipe ends conforming to Gruvlok grooving specifications.

Figure 7012 Coupling Flanges

The Gruvlok Figure 7012 coupling flange allows direct connection of Class 125 or Class 150 flanged components to a grooved piping system. Available in 2" through 24" sizes, with 2" through 12" sizes using two interlocking halves hinged for ease of handling and assembled with a latch bolt. Sizes 14" through 24" are cast in four segments. Precision machined bolt holes and mating surfaces ensure concentricity and flatness for proper fit-up with flanged, lug, and wafer-style equipment. A specifically designed gasket provides a leak-tight seal on both the pipe and the mating flange face. The 7012 flange cannot be assembled directly to Series 7700 butterfly valves per Gruvlok installation instructions.

Gaskets and Lubricants

Gruvlok gasket selection is the critical technical decision in every grooved piping specification. EPDM gaskets are for water, glycol, and HVAC service but are not suitable for petroleum, oil vapors, or vegetable and mineral oil applications. Nitrile gaskets are recommended for petroleum and oil-vapor applications but are not for use in hot water or hot air service. Grade L silicone gaskets require Gruvlok Xtreme Lubricant and should not be used with other lubricant types. For temperatures above 150°F, Gruvlok Xtreme Silicone Lubricant (part 390162881) is required, applied to all gasket surfaces internal and external, per Gruvlok coupling installation instructions.

How to Choose Gruvlok Fittings

Flexible vs. rigid coupling is the first specification decision. The Figure 7001 flexible coupling allows angular deflection and linear movement between pipe ends, making it the standard choice for most hydronic, HVAC, and mechanical piping where vibration isolation or thermal movement accommodation is desired. The Figure 7401 Rigidlok is specified where a fully rigid joint is required, such as at equipment connections or in systems where pipe movement must be restrained.

Gasket material must match the service fluid. EPDM is the standard selection for water, glycol, and HVAC service. Nitrile covers petroleum and oil-vapor applications. Grade L silicone handles high-temperature and specialty fluid applications. Confirming the service fluid and operating temperature before specifying gaskets prevents incompatible material selection that could cause gasket failure.

Pipe groove specification must match Gruvlok requirements. Gruvlok couplings and fittings require pipe ends grooved in accordance with Gruvlok grooving specifications. Pipe ends must be free of indentations and projections that would prevent proper gasket sealing. Always use Gruvlok lubricant on the gasket during coupling assembly per Gruvlok installation instructions.

For anyone asking whether Gruvlok fittings work with standard-weight and lightweight pipe: the Figure 7001 and 7401 couplings are designed for use with both standard-weight and roll-grooved lightweight pipe, as specified in Gruvlok engineering documentation. Heavy-wall pipe schedules may require different groove dimensions; confirm pipe schedule against Gruvlok grooving specifications before cutting grooves.

FAQs

What is the working pressure rating of the Gruvlok Figure 7001 coupling?
The Gruvlok Figure 7001 standard flexible coupling is rated to 1,000 PSI working pressure per Gruvlok product documentation on SupplyHouse. The coupling achieves this rating without excessive casting weight and is suitable for mechanical, plumbing, process piping, and HVAC hydronic applications.

What is the difference between Gruvlok Figure 7001 and Figure 7401 couplings?
The Gruvlok Figure 7001 is a flexible coupling that allows angular deflection and linear movement between pipe ends, and reduces pipeline noise and vibration transmission. The Figure 7401 Rigidlok is a rigid coupling that grips the pipe using a specialized housing design with precisely sized tines, producing a fully rigid joint connection. The Rigidlok is specified for applications where pipe movement must be restrained or a rigid joint is required by design.

What gasket materials are available for Gruvlok couplings and what fluids are they rated for?
Gruvlok couplings are available with EPDM gaskets for water, glycol, and HVAC applications (not for petroleum); nitrile gaskets for petroleum, oil vapors, and mineral oils (not for hot water or hot air); and Grade L silicone gaskets for specialty high-temperature applications requiring silicone. Gasket material must be matched to the service fluid and temperature per Gruvlok engineering documentation.

What pipe size range do Gruvlok fittings cover?
Gruvlok standard fittings are available through 24" nominal pipe size per Gruvlok product documentation. The SupplyHouse Gruvlok fittings category includes 90-degree and 45-degree elbows, concentric reducers, tees, reducing tees, caps, coupling flanges, and branch clamps across the available size range.

When should Gruvlok Xtreme lubricant be used instead of standard lubricant?
Gruvlok Xtreme Silicone Lubricant is required for all Gruvlok coupling assemblies at service temperatures above 150°F, applied to all gasket surfaces internal and external, per Gruvlok coupling installation instructions. Standard lubricant is used for ambient-temperature and moderate-temperature HVAC and plumbing applications. Grade L silicone gaskets also specifically require Xtreme Lubricant; using other lubricant types with Grade L gaskets is not permitted per Gruvlok documentation.