Midland Industries 64041212 Straight Adapter 3/4 in Orb X Nptf

Product Description

The MIDLAND INDUSTRIES 64041212 is a straight hydraulic adapter designed to connect a 3/4-inch Female O-Ring Boss (ORB) port to a 3/4-inch Male NPTF fitting. Manufactured from steel, this adapter is rated for a maximum operating pressure of 2900 psi and a maximum operating temperature of 375 degrees F. The thread specifications are 1-1/16-12 on the ORB end and 3/4-14 on the NPTF end. It is part of the 6404 Series of Female O-Ring to Male NPT adapters and is sized for direct, single-piece conversion between these two common hydraulic connection standards.

This adapter is used in hydraulic plumbing applications where an O-Ring Boss port on a valve, manifold, pump, or cylinder must be transitioned to a male NPTF threaded line or component. The ORB end uses a face-sealing O-ring to eliminate thread-path leakage, while the NPTF thread provides a dry-seal mechanical connection on the mating side. Typical installations are found in mobile hydraulic equipment, industrial fluid power systems, and agricultural machinery. The 2900 psi pressure rating makes it suitable for medium- to high-pressure hydraulic circuits.

Key Features

• 3/4-inch Female O-Ring Boss to 3/4-inch Male NPTF straight configuration
• Maximum operating pressure of 2900 psi
• Maximum operating temperature of 375 degrees F
• Thread sizes: 1-1/16-12 (ORB) x 3/4-14 (NPTF)
• Steel construction for durability in hydraulic service
• Part of the 6404 Series Female O-Ring to MNPT adapter line

Compatibility

Designed for use in hydraulic systems requiring a Female O-Ring Boss to Male NPTF straight adapter connection within the 3/4-inch port size range.

Installation Notes

Installation is typically performed by a hydraulic technician or pipefitter. Depressurize and isolate the hydraulic circuit completely before removing or installing any fittings. The ORB end requires a properly seated and lubricated O-ring for a leak-free face seal; inspect the O-ring before assembly. Tighten NPTF connections to the appropriate engagement per applicable fluid power standards such as SAE J1453 or ANSI B1.20.3 - do not over-tighten, as NPTF threads rely on controlled interference for sealing.