Revolving / Stationary Self Opening Die Heads DR

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Revolving / Stationary Self Opening Die Heads DR

External Threading Revolving / Stationary Self Opening Die Heads DR

Self-Opening Circular Chaser Die-Heads: DR

📌 Purpose:

DR 4-Chaser Diehead – Reliable Threading for Revolving Spindle Machines

The DR style diehead is a robust 4-chaser threading tool designed for use on machines equipped with revolving spindles. Engineered for durability and versatility, it is well-suited for a wide range of threading applications.

DR Series Self-Opening Revolving Die Heads Designed for use on machines with revolving spindles, DR die heads are essential tools in the threading industry, delivering high production rates, operational economy, and consistent accuracy. Their rugged construction and adaptable design make them ideal for both right-hand and left-hand thread cutting.

🏗️ Machine Compatibility:

Model DR Die Heads can be seamlessly mounted on:

v  Centre lathes

v  Capstans and turret lathes

v  Semi-automatic machines

v  Drilling machines and Milling machines

v  Radial drilling machines

v  CNC, VMC and HMC machines

 

🛠️ DR Die Head Technical Data

Diehead Model	Threading Capacity (Metric)	Threading Capacity (Inch)	Suitable Chaser Set	ØA	B	C	ØD	ØE	ØF
DR 3/8” *	5 – 9 mm	3/16” – 3/8”	3/8”	66.80	43.69	27.43	25.40	14.22	35.05
DR 9/16”	7 – 14 mm	1/4” – 9/16”	9/16”	73.15	47.75	18.03	38.10	16.00	46.74
DR 13/16”	7 – 14 mm	1/4” – 9/16”	13/16”	92.20	52.32	20.32	38.10	22.35	49.28
DR 1”	7 – 20 mm	1/4” – 13/16”	1”	103.12	57.15	20.32	38.10	26.92	50.80
DR 1-1/16”	10 – 25 mm	3/8” – 1”	1-1/16”	98.55	52.32	20.32	38.10	28.70	50.80
DR 1-5/8”	13 – 27 mm	1/2” – 1-1/16”	1-5/8”	123.95	57.15	23.37	69.85	42.93	88.90
DR 2”	13 – 41 mm	1/4” – 1-5/8”	2”	130.30	57.15	23.37	69.85	44.45	88.90

Diehead Model	Threading Capacity (Metric)	Threading Capacity (Inch)	G	H	ØI	J	K	M	Approx Weight (Kg.)
DR 3/8” *	5 – 9 mm	3/16” – 3/8”	9.65	71.12	14.22	21.84	12.45	4.57	1.000 Kg.
DR 9/16”	7 – 14 mm	1/4” – 9/16”	14.22	65.79	23.62	12.45	1.27	6.10	1.700 Kg.
DR 13/16”	7 – 14 mm	1/4” – 9/16”	14.22	72.64	23.62	11.68	1.27	6.10	3.000 Kg.
DR 1”	7 – 20 mm	1/4” – 13/16”	14.22	77.47	27.94	12.45	1.27	6.35	3.800 Kg.
DR 1-1/16”	10 – 25 mm	3/8” – 1”	14.22	72.64	27.94	11.68	1.27	6.10	3.000 Kg.
DR 1-5/8”	13 – 27 mm	1/2” – 1-1/16”	19.05	80.52	27.94	14.73	1.27	6.35	6.200 Kg.
DR 2”	13 – 41 mm	1/4” – 1-5/8”	19.05	105.66	44.45	14.73	1.27	6.35	6.800 Kg.

📝 Important Ordering Note: When placing an order for DR models, please specify the required shank [ e.g., Straight Shank, Straight Coolant] & yoke to ensure compatibility with your machine spindle. Additionally, kindly purchase the appropriate chaser set based on the material you intend to process. [ Special Shanks & yoke : Supplied on request at an additional cost, depending on the availability of the required shank. ] {*3/8" DR is offered exclusively with an integral 1" diameter shank.}

Engineered for reliability, speed, and precision in high-performance threading operations.

🤖 Smart Function:

🧭 Function	📖 Description	🎯 Benefit
🔓 Self-Opening & Closing Mechanism	Integrated cam and stopper system automatically opens the die-head at the preset thread length and closes it securely	Eliminates spindle reversal and significantly improves threading cycle efficiency
🎯 Micrometric Diameter Adjustment	Knurled screw with engraved calibration lines	Enables precise thread sizing across production runs
🔄 Circular Chaser Technology	Reduces rubbing and enhances chip clearance	Improves thread quality and extends tool life
🧰 Universal Machine Fit	Compatible with lathes, drilling, milling, CNC, VMC, HMC machines	Maximizes setup flexibility across manual and automated systems
🔁 Bidirectional Threading	Supports both right-hand and left-hand threads with dedicated chasers	Expands threading capability for diverse applications
🧲 Snap-Action Opening	Die-head opens automatically via cam disengagement	Boosts repeatability and operator productivity
⚙️ High-Speed Threading	Operates efficiently from 100–600 RPM	Delivers accurate threading at high speeds
🛡️ Precision-Ground Components	Rigid build with close-tolerance parts	Reduces vibration and enhances surface finish
🔧 Quick Chaser Change	Four-screw cover plate for fast replacement	Minimizes downtime and simplifies maintenance
🧪 Material Compatibility	Optimized for MS, CI, low carbon steel, aluminum, copper, and steel	Ensures reliable threading across common industrial metals

🔑 Key Advantages:

v  Universal Machine Fit: Universal Machine Compatibility Designed for maximum adaptability; DR die-heads are compatible with horizontal lathes for short-length threading lengths, as well as vertical drilling,  milling machines and radial drilling machines with rotating, reversing spindles - when equipped with a special MT shank for short-length threading. They are also suitable for CNC, VMC and HMC machines in short-threading applications, provided that each threading cycle allows for manual door-opening to enable die-head locking. This versatility makes them a dependable choice for both traditional and automated machining setups.

v  Threading Flexibility: Supports both right-hand and left-hand threads with dedicated chasers for each.

v  No Spindle Reversal Required: Once threading is complete, the DR model automatically opens using a stopper mechanism - eliminating the need to reverse the machine spindle.

v  Chaser Compatibility: Accepts all standard Circular HSS chase sets, only the proper chaser size is required.

v  4-Chaser Configuration: Provides efficient and accurate threading for general-purpose use.

v  Material Suitability: Optimized for ductile metals like MS, CI Casting, Low Carbon Steel, Aluminium and Copper, and also suitable for Steel.

v  Cost-Efficient Threading: Achieve precise, high-speed threading across multiple sizes using a single die-head - minimizing tooling costs and maximizing productivity. Ideal for high-volume production environments where accuracy and efficiency are critical.

v  User Requirement: For best performance, operation by a skilled machinist & semi-skilled machinist is recommended.

v  High-Speed Output: Enables threading faster than SDH Model and suited for rapid multi-size threading at low cost.

⚡️Quick & Easy Installation – Model DR:

Installing Die Heads DR is designed to be efficient and straightforward, especially for high-production threading applications. The DR model is a self-opening circular chaser diehead used on machines with revolving spindles. Here's how to get it up and running quickly.

Quick Installation Guide for DR Die Heads

1. Inspect and Prepare

Ø  Clean the diehead thoroughly.

Ø  Check for wear on the yoke spool and chaser blocks.

Ø  Confirm compatibility with your machine’s spindle and thread direction.

2. Insert Circular Chasers

Ø  Select the correct chasers for your thread size and pitch.

Ø  Slide each chaser into its designated block slot.

Ø  Secure using standard screws and serrated bushings.

3. Mount the Die Head

Ø  Attach the diehead to the machine spindle using the appropriate modular shank adapter.

Ø  Modular shank system allows easy swapping between machines.

4. Set Threading Parameters

Ø  Adjust the machine’s feed rate and depth to match the diehead’s cutting range.

Ø  DR dieheads support both right-hand and left-hand threads.

5. Test and Fine-Tune

Ø  Run a trial threading pass to check alignment and thread quality.

Ø  Make fine adjustments as needed for optimal performance.

Chaser Sets for DR:

Crafted from high-speed steel (HSS), these chasers are available in various thread angles and profiles to suit a wide range of threading applications. Ideal for materials with hardness up to 20 HRC.

🎯 High-Precision Features:

v  Automatic Self-Opening Design: Enables efficient, hands-free threading operations.

v  Circular Chaser Technology: Reduces rubbing, enhances chip clearance, extends tool life, and ensures smooth thread profiles.

v  270° Regrind Capability: Chasers can be reground through a full 270 degrees, maintaining consistent throat geometry throughout their life.

v  Heat Dissipation: Robust chaser bodies and external mounting facilitate heat dissipation for longer tool and machine life.

v  Consistent Thread Accuracy: Delivers uniform, high-quality threading across large production volumes, ensuring minimal deviation and superior fit.

v  Self-Opening and Self-Closing Mechanism: A built-in snap-action system automatically opens and closes the die-head at the pre-set thread length, delivering precise control and consistent cycle repeatability.

v  Fine Thread Diameter Adjustment: Equipped with knurled adjusting screws and engraved calibration lines for micrometric regulation of thread size.

v  Precision-Ground Components: All critical parts are manufactured to close tolerances, enabling seamless assembly, smooth performance, and reliable interchangeability.

v  Stable Cutting Performance: Rigid construction and optimized cutting dynamics reduce vibration, enhance surface finish, and extend tool life.

v  Speed-Optimized Operation: Performs efficiently within a wide RPM range (100–600), with excellent results even on materials with hardness up to 20 HRC.

v  Precision Engineering: Designed for high-speed, accurate thread cutting, suitable for low-volume production and heavy-duty jobs alike.

v  Rugged Construction: Built to withstand demanding production environments.

v  Bidirectional Threading: Suitable for both right-hand and left-hand threads.

v  External Yoke Spool Operation: Enables smooth and reliable opening and closing of the head.

📐 Technical Operating Range:

v  Threading Speed: Recommended threading speed: 100–600 RPM, depending on material hardness, thread size/pitch, and chaser condition. (Always use coolant for finish-grade threads and longer tap life.)

v  Material Hardness: 0–20 HRC

v  Maximum Threading Length: Offers unlimited threading lengths on horizontal lathes, while supporting short-length threading applications on vertical drilling machines, milling machines, CNC, and VMC setups.

🛠️ Maintenance Note:

To extend the life of this tapping attachment or any die head, die holder, or tap chuck avoid constant use at upper or lower limit capacities. Consider rotating between two or three units for heavy-duty applications.

🎯 Special Shanks: Please specify the desired shank type (e.g., Straight Shank, Straight Coolant) to ensure compatibility with your machine spindle. These are available upon request and may incur additional charges, subject to availability.

🔩 Key Highlights for Die Head Maintenance

🛠️ Functional Inspection

v  Chaser Springs: Must operate smoothly no chips, no bending.

v  Pins in Block: Ensure they are straight and not fractured.

v  Cams on Die head Cup: Check edges for noticeable wear, which affects chaser movement.

v  Guide Pins: Must be rigid within the adjusting plate. Replace if there's any play.

📏 Alignment & Geometry

v  Adjusting Plate: After replacing guide pins, inspect for warping. Warped plates cause misalignment.

v  Floating Bushing: Should protrude visibly from the body hole to maintain guiding accuracy.

🔍 Wear Components Check

v  Plunger: Remove and assess the control tip edge any damage can disrupt retraction timing.

v  Spring Plunger: Ensure the spring retains good compression before reassembly.

🧼 Bonus Tips

v  Always clean components of chips and debris before inspection.

v  Lubricate wear points appropriately after each maintenance cycle.

v  Document findings for each die head to track performance over time.

🔧 Advantages of Circular Chasers

🌀 Optimized Shape for Performance

v  The circular design ensures minimal rubbing just behind the cutting edge, promoting better lead control.

v  Reduces friction and wear, resulting in smoother threads and extended chaser life.

v  The chaser’s solid body and external mounting allow for rapid heat dissipation and efficient chip removal ideal for higher cutting speeds.

🎯 Consistent Accuracy

v  Delivers precision threads immediately, eliminating the need for trial-and-error adjustments.

v  Features annular thread forms with a factory-set helix angle that remains consistent throughout the tool’s life.

🔄 Superior Regrinding Capability

v  Can be re-ground through a full 270°, far surpassing the lifespan of thin-blade alternatives.

v  The built-in throat grind maintains its geometry even after multiple re-sharpenings.

v  Simplified grinding process ensures accurate, repeatable results with minimal effort.

⚙️ Quick and Easy Replacement

v  Chasers are pre-mounted and precisely ground, enabling fast installation without disturbing the setup.

v  Replacement takes seconds, thanks to user-friendly mechanisms like a screw turn or reset handle—much faster than traditional systems.

🔁 Full Interchangeability

v  Circular tools are interchangeable between rotating and non-rotating heads, size for size.

v  By adjusting the grind, the same chaser can be optimized for a wide range of materials, enhancing versatility.

🧩 Exclusive Modular Shanks

v  Unique to our circular chaser systems, modular shanks allow the same head to be used across multiple machines.

v  Reduces tooling inventory, improves utilization, and minimizes downtime.

v  Available in standard and coolant-induced versions across various sizes (see pages 11).

🔩 4-Chaser Dieheads

v  Offer high production efficiency, accuracy, and cost-effectiveness.

v  Their size range and interchangeability make them one of the most versatile threading tools available.

v  Modular shank design allows for easy adaptation to different machines and reduces replacement costs.

🧱 Replaceable Plunger Wear Insert

v  All dieheads include a hardened, replaceable plunger wear insert.

v  Unlike older designs with built-in grooves, this insert can be replaced affordably, extending the life of the diebody.

v  Prevents costly diebody replacements and ensures long-term durability.

🔩 Chaser Thread Standards

Thread	Full Form	Description
NPT	National Pipe Taper	Tapered thread used in U.S. pipe fittings. Creates a seal via thread interference.
BSP	British Standard Pipe	Common in Europe and Asia. Includes BSPT (tapered) and BSPP (parallel) threads.
BSW	British Standard Whitworth	Coarse thread with rounded crests and roots. Used in older British machinery.
UNF	Unified National Fine	Fine-pitch thread used in precision applications. Part of the Unified Thread Standard.
UNC	Unified National Coarse	Coarse-pitch thread for general fastening. Also part of the Unified Thread Standard.
Metric	ISO Metric Thread	International standard. Uses millimeter-based pitch and diameter.

🧰 Where They're Commonly Used

v  NPT: Plumbing, gas lines, hydraulic systems (mostly in North America)

v  BSP: Water and fluid systems (Europe, Asia, Australia)

v  BSW: Restoration, vintage British equipment

v  UNF/UNC: Automotive, aerospace, general engineering (U.S. and Canada)

v  Metric: Global standard for bolts, screws, and fasteners

🏭 Chaser Material -  Performance Comparison

Feature	M2	M2 + Coating	M35	M35 + Coating
Base Material	HSS (no cobalt)	Same + surface coating	HSS + 5% cobalt	Same + surface coating
Heat Resistance	Moderate	Improved	High	Excellent
Wear Resistance	Good	Better	Very Good	Superior
Tool Life	Standard	Longer	Long	Longest
Thread Finish	Acceptable	Smoother	Clean	Best-in-class
Cost	Low	Slightly higher	Higher	Highest
Ideal Use	Mild steel, alloys	Medium-duty runs	Stainless, tool steel	High-speed, tough jobs

⚙️ Estimated Production Ratios (Relative Tool Life)

Chaser Type	Relative Tool Life	Typical Usage Ratio*
M2	1× (baseline)	40–50%
M2 + Coating	~1.5×	20–25%
M35	~2×	15–20%
M35 + Coating	~2.5–3×	10–15%

*These ratios reflect how often each type might be used in a mixed production setup, assuming cost and performance are balanced.

🔍 Production Insights

v  M2 is suitable for short-run jobs or general-purpose threading where cost is a priority.

v  M2 with coating offers better performance in medium-duty production, especially with coolant-assisted threading.

v  M35 is built for demanding materials like stainless steel and excels in automated setups.

v  M35 with coating is the top-tier choice for continuous, high-speed production with minimal downtime.

💡 Decision Tip

If your production involves frequent threading of hard materials or long cycle times, investing in M35 with coating can reduce tool changes and improve consistency. But for cost-sensitive, low-to-medium complexity jobs, M2 or M2 with coating may be more economical.

🎯 "Intelligent Quick-Analysis Tool Designed For Discerning Business Customers." 🎯

 

🛠️ DR Model Self-Opening Die-Heads – Dimensional Range Smart Overview

Diehead Model	Threading Capacity (Metric)	Threading Capacity (Inch)	Suitable Chaser Set	Approx Weight (Kg.)
DR 3/8”	5 – 9 mm	3/16” – 3/8”	3/8”	1.000 Kg.
DR 9/16”	7 – 14 mm	1/4” – 9/16”	9/16”	1.700 Kg.
DR 13/16”	7 – 14 mm	1/4” – 9/16”	13/16”	3.000 Kg.
DR 1”	7 – 20 mm	1/4” – 13/16”	1”	3.800 Kg.
DR 1-1/16”	10 – 25 mm	3/8” – 1”	1-1/16”	3.000 Kg.
DR 1-5/8”	13 – 27 mm	1/2” – 1-1/16”	1-5/8”	6.200 Kg.
DR 2”	13 – 41 mm	1/4” – 1-5/8”	2”	6.800 Kg.

🔩 DR Series Revolving/Stationary Self-Opening Die Head – Quick Smart Summary

Designed for precision external threading in both manual and automated setups, the DR Series die heads feature automatic opening, circular chaser technology, and universal machine compatibility—ideal for high-speed, high-volume production environments.

🔑 Key Features

v  🔓 Self-Opening Mechanism: Cam and stopper system disengages die-head automatically at preset thread length—no spindle reversal needed.

v  🎯 Micrometric Diameter Control: Knurled screw with calibration lines allows precise thread sizing.

v  🔄 Circular Chaser Technology: Reduces rubbing and improves chip clearance for better finish and tool life.

v  🧰 Universal Compatibility: Fits lathes, drilling, milling, CNC, VMC, and HMC machines.

v  🔁 Thread Direction Flexibility: Supports both right-hand and left-hand threads with dedicated chasers.

v  🧪 Material Versatility: Suitable for MS, CI, low carbon steel, aluminum, copper, and steel.

⚙️ Operating Highlights

v  Threading Speed Range: Efficient performance between 100–600 RPM depending on material and chaser condition.

v  Thread Length Capability: Unlimited on horizontal lathes; short-length threading supported on vertical and CNC machines.

v  Quick Chaser Replacement: Four-screw cover plate enables fast maintenance.

📌 Safety & Performance Tips

v  Use Coolant: Apply cutting fluid to enhance finish and extend tool life.

v  Avoid Overload: Rotate between units for heavy-duty use; avoid extreme capacity limits.

v  Correct Setup: Ensure proper chaser seating and handle alignment before operation.

v  Trial Cut First: Always verify thread size with a trial cut before full production.

🔩 DR Series Revolving/Stationary Self-Opening Die Head – Quick Smart Analysis

Aspect	Details
🔧 Type	Revolving/Stationary Self-Opening Die Head – engineered for high-speed external threading
⚙️ Function	Enables automatic die-head opening at preset thread length without spindle reversal
🔄 Mechanism	Cam and stopper system disengages die head smoothly after threading
📐 Thread Range	Accommodates a wide range of metric and imperial thread sizes using circular chasers
🛠️ Applications	Ideal for mass production threading on lathes, CNCs, VMCs, HMCs, and milling machines
✅ Advantages	Enhances threading speed – Improves surface finish – Reduces chaser wear and operator effort
🏭 Use Case	Compatible with center lathes, turret lathes, drilling, milling, CNC, VMC, and HMC setups

v  Overview : The DR Series Revolving/Stationary Self-Opening Die Heads are engineered for high-speed, precision external threading without the need for spindle reversal. Key features include:

Ø  Self-opening mechanism for smooth, automatic disengagement

Ø  Right- and left-hand thread compatibility with dedicated chasers

Ø  Micrometric thread diameter adjustment via calibrated knurled screw

Ø  Two-cut threading mode (roughing and finishing) without tool change

Ø  Precision-ground components for vibration-free performance and superior finish

v  Tap Monitoring Integration (when paired with automated systems)

Ø  Real-time detection of torque spikes, misalignment, and dull chasers

Ø  Evaluation of thread engagement and clutch response

Ø  Alerts for inconsistencies in thread profile and feed rate

v  Benefits :

Ø  Reduces downtime through early fault detection

Ø  Improves thread quality and extends tool life

Ø  Supports predictive maintenance and operator feedback

v  Ideal For : High-volume or precision threading environments where consistency, speed, and tool protection are essential—such as CNC, VMC, HMC, and turret lathe setups.

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