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GRUVLOK Metal Pipe Straight: Concentric Reducer, 4 in x 3 in, Ductile Iron - Grooved Pipe Fittings
GRUVLOKGrooved Pipe Fittings

GRUVLOK Metal Pipe Straight: Concentric Reducer, 4 in x 3 in, Ductile Iron

The GRUVLOK Metal Pipe Straight: Concentric Reducer is a grooved pipe fitting in ductile iron, sized 4 in x 3 in, with a maximum operating pressure of 300 psi @ 150° F. 3G Electric sources this OEM part (MPN…

SKU 3G-OTH-460912

Brand
GRUVLOK
Item
Metal Pipe Straight: Concentric Reducer, 4 in x 3 in, Ductile Iron
Category
Grooved Pipe Fittings
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Technical Specifications

GRUVLOK
Manufacturer Part Number
0390028660
Type
4 in x 3 in, Ductile Iron, 300 psi @ 150° F
Fitting Pipe Size
4 in x 3 in
Maximum Operating Pressure
300 psi @ 150° F
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GRUVLOK Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The GRUVLOK Metal Pipe Straight: Concentric Reducer is a grooved pipe fitting in ductile iron, sized 4 in x 3 in, with a maximum operating pressure of 300 psi @ 150° F. 3G Electric sources this OEM part (MPN 0390028660) across 14 industrial departments, with specialist expertise in combustion, pumps and controls as an authorised distributor.

Frequently Asked Questions

What is a GRUVLOK concentric reducer used for?

A GRUVLOK concentric reducer connects pipes of different diameters in grooved piping systems, typically in fire protection, HVAC, or industrial process lines. It transitions flow from a 4 in to a 3 in pipe while maintaining system pressure up to 300 psi @ 150° F.

What are the specifications of the GRUVLOK 4 in x 3 in concentric reducer?

This GRUVLOK concentric reducer is a ductile iron grooved fitting with a 4 in x 3 in pipe size. It has a maximum operating pressure of 300 psi @ 150° F. The OEM part number is 0390028660. 3G Electric supplies this part across 14 industrial departments.

Where to buy a GRUVLOK concentric reducer worldwide?

3G Electric supplies the GRUVLOK concentric reducer (MPN 0390028660) to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this ductile iron grooved fitting.

How to install a GRUVLOK grooved concentric reducer?

Installation follows standard grooved-pipe fitting practice: lubricate the gasket, place it over the pipe ends, then slide the reducer into position. Tighten the coupling bolts evenly to the manufacturer’s torque specification. Always verify pressure rating and pipe alignment before pressurizing the system.

Used in

Common applications for GRUVLOK
Fire-protection systems — GRUVLOK ductile iron butterfly valves (e.g., SKU 3DVX7) for water-based sprinkler and standpipe networks.
Chemical processing — GRUVLOK carbon steel butterfly valve with 316 stainless steel disc (SKU 60WR76) for handling corrosive media.
General water distribution — GRUVLOK ductile iron butterfly valve with EPDM seat (SKU 60WR98) for municipal or industrial water lines.
HVAC piping — GRUVLOK grooved-end butterfly valves for chilled water or hot water systems requiring quick installation.
Industrial process control — GRUVLOK lever-operated butterfly valve (SKU 60WR82) for throttling or isolation in chemical media applications.

GRUVLOK Products

3G Electric supplies GRUVLOK grooved pipe fittings. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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