Heat Treatment

RKFL has atmospheric controlled sealed quenching furnaces. It has also undertaken Plug Quenching and Carburisng meticulously upto the desired case depth as desired by the clients. State-of-the-art hardening and tempering furnaces are PLC controlled and have integral graphic recorder.

We use Induction Heaters for our Forgings and also in Ring Rolling. RKFL has a fully automated Induction heater of Inducto Heat/Induction Therm make with pyrometer fitted capable of accept and reject mechanism.

In the new Press Plant the Furnace is run by SCADA control system and entire heat treatment is automatic.

The furnace is a continuous process pusher type of furnace; the hardening is gas propane heated and the tempering is electrically heated.

Pyrometer (TUS) & System Accuracy Test (SAT) conducted at specified frequency and as per CQI9. At RKFL CQI9 Audit is conducted at regular intervals.

Plant 5 is fully equipped with alarm annunciators and includes:

1. Quench Delay Fault
2. Burner Fault
3. Temperature high or Low (Hardening / Tempering)
4. RC Fan Fault
5. Agitator Stop
6. Heater Fault
7. Polymer Temperature High or Low from high and Low Set Point or Oil Temperature High or low from high and Low Set Point

Hardening Process

Tempering Process

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Controlled Cooled Micro-alloyed Steel

Property requirement as per STD 1129-1

Steel V-2910 Stal V-2910

1. Composition

2. Mechanical Properties

3. Microstructure

Individual cooling from forging temperature to 600 +/- 25^oC. Uncontrolled cooling follows this. The structure of the steel shall be pearlite ferritic. Bainite content max 10%.

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Technical parameter- To achieve Property requirement as per STD 1129-1

Raw material:

Sourcing: Customer approved source & Customer Approved Alloy Design

#Austenite grain coarsening is also controlled by controlling Time-Temperature in induction billet heaters

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Technical parameter-To achieve property requirement as per STD 1129-1

Forging Press at RKFL- 6300T

Typical parameters for the hot forging of the Microalloy Steel

1. Heating temperature (Through induction) 1200 ~ 1250 deg C
2. Forging temperature: 1150 ~ 1200 deg C
3. Trimming temperature: 1000 ~1100 deg C
4. Loading to conveyor temperature: 970~1030 deg C
5. After trimming & straitening the Knuckles to be loaded into a enclosed conveyor.
6. The cooling speed should be controlled at 50 deg C./min +/- 10^oC.

To control the cooling the conveyor will be equipped with forced draft & induced draft.

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Recently developed MA steel Forging at RKFL

Material: 38MnSiVS5

1. Composition

2. Mechanical properties

3. Microstructure

Microstructure Remarks:
Grain size (As per ASTM E112-12) : ASTM 6
Matrix of ferrite & pearlite with no bainite.

#The above material was found acceptable with all respect

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Process facilities & Capability at RKFL- A Snap Shot

Controlled Cooling Facility

1. Cooling conveyor of 14meter length equipped with speed control facility
2. Two nos. forced draft at both ends and two induced draft at middle zones are designed with variable draft control so that air flow rate can be customized as per required thermal profile
3. Four nos. of IR pyrometers are also provided at designated places which are connected with SCADA system for continuous monitoring / control to maintain the thermal profile inside the conveyor.

By virtue of being a Higher Vanadium grade (0.16-0.22%), this steel is susceptible to bainitic precipitation and hence would be needing a lower cooling rate compared to a lower Vanadium grade (0.08-0.13%)

An well equipped Metallurgical Laboratory facility shall be an advantage in perfect and timely evaluation and control of mechanical and micro-structural properties.