Semi-automatic pipe threading machine Oster 784

Overview
The Oster 784 threading machine is a purpose-built, industrial 4" capacity pipe and bolt threading machine. Designed for shop or jobsite use where production rates, part size and thread quality are primary requirements. Built with precision-machined components and a fabricated base for sustained industrial operation.

Capacities
Standard Pipe Range: 3/8" to 4"
Extra Pipe Range*: 1/4"
Standard Bolt Range: 1/2" to 3"
Extra Bolt Range*: 3/8" to 11/16"

General Specifications
Spindle Speeds, Variable: 16-23-35-51
Carriage Travel: 15"
Length: 5' 9"
Width: 3' 5"
Height: 4' 4"
Net Weight: 1950 lbs.
Shipping Weight: 2300 lbs.

Advantages of the Oster 784 4" Capacity Threading Machine

• Heavy-duty construction and industrial components for continuous use.
• Dies cut full taper on 2" pipe, wider than competitors' dies.
• Large heavy-duty dies available for 2.5"–4" sizes.
• Standard gripping covers 1/2"–4" pipe and 5/8"–3" bolts; optional auxiliary gripping chuck extends to 1/8" pipe / 1/4" bolt.
• Cast iron carriage, precision machined parts and fully fabricated base.

Threading Sizes / Thread Forms

• NPT (National Pipe Taper)
• NPTF (National Pipe Taper-Fuel, Dryseal)
• NPS (National Pipe Straight)
• NPSL (National Pipe Straight-Locknut)
• BSPT (British Standard Pipe Taper)
• BSPP (British Standard Pipe Parallel)
• UNC (Unified Coarse Pitch Threads)
• UNF (Unified Fine Pitch Thread)
• Metric Bolt Coarse
• Metric Bolt Fine
• ACME
• Right and Left Hand Threads

Considerations

• Machine is operator-driven; no specialized certification required for basic operation.
• Integration for full automation is limited; suitable for manual and semi-automated workflows.

Features
Cut-Off, Reaming & Chamfering
Lathe-type cut-off and chamfer tools are mounted on the back of the die head on a cross rail. The reamer is swing-type for accurate internal finishing.

Lever Operated Dieheads
Two quick-opening, removable lever-operated die heads cover the full pipe and bolt range. Both include a positive locking device and simultaneous die adjustment for over- or undersize threads. Die changes are fast and tool-free.

Motor Control
Reversing magnetic starter with push-button station and a JOG-RUN selector for spindle jogging to facilitate gear shifting. Input 230/460V; machine control converted to 120V for operator safety.

Motor Mount & Transmission
Motor is mounted on an adjustable plate and drives through three V-belts to a selective gear-type transmission. V-belts dampen shock and ensure quiet operation. All shafts are ball-bearing mounted.

Standard Equipment Furnished

• Dieheads - Two die heads: one for sizes up to 2", another for 2-1/2" to 4".
• Dies - Two sets covering standard pipe range 1" through 4". RIGHT hand only. One set high-speed steel Symbol QUAD (1"–2") and one set high-speed steel Symbol 74 (2-1/2"–4"). Left-hand threads available with optional die head and dies.
• Reamer - Swing-type reamer.
• Cutter - Lathe-style blade cut-off tool with double V-block centering device.
• Chamfer Tool - Mounted in cut-off block.
• Front Chuck - Wrenchless three-jaw universal gripping chuck.
• Rear Centering Chuck - Wrenchless three-jaw universal centering chuck.
• Motor - 5 hp, 1800 rpm, 3-phase, 60 Hz. 230 or 460 V (other motors available).
• Motor Control - Reversing magnetic starter and push-button station with safety 120V control circuit.
• Gage - Direct-reading drum type mounted on carriage hand wheel.
• Oil Pump - V-belt driven by drive motor.
• Oil - Thread cutting oil, ten gallons — Oster "OSTO".

Accessories

• Victaulic type grooving tool attachment — ensures correct groove depth, width and distance from pipe end (optional).
• Rear gripping chuck No. 02969 — replaces rear centering chuck; wrenchless three-flange jaws for universal gripping.
• Additional accessories: No. 200 nipple chuck, No. 4 nipple chuck.

Technical Specifications

• Model: Oster 784
• Standard pipe capacity: 3/8" to 4"
• Extra pipe capacity: 1/4"
• Standard bolt capacity: 1/2" to 3"
• Extra bolt capacity: 3/8" to 11/16"
• Spindle speeds (variable): 16-23-35-51
• Carriage travel: 15"
• Overall length: 5' 9"
• Overall width: 3' 5"
• Overall height: 4' 4"
• Net weight: 1950 lbs.
• Shipping weight: 2300 lbs.
• Motor: 5 hp, 1800 rpm, 3-phase (230/460 V)