Download - Lesson Plan for Fuze Ffv 651 Heat
LESSON PLAN
COURSE : BASIC COURSE ON ARMAMENT
SUBJECT: FUZES : Time – 90 Minutes
TOPIC : FUZE FFV 651
SL. No.
Sub Topic
Content Training Aids Time
01 General Classification
Type
End Use
Black Board
-do-
-do-
15 min
Sl. No.
Sub Topic Content Training Aids
Time
2. Construction Fuze FFV 651
Important components of fuze
Slides 30 min
3.
4.
Functioning
Proof
Fuze FFV 651
Tests on Fuze FFV 651
Proof of Fuze FFV 651
Slides
Black Board/ slides
30 min
15 min
Definition of fuze:- Fuze is a device which detonates the projectile at predetermined place and time. The fuzes can be classified as per its position in ammunition, its action, type of mechanism used.
In HEAT amn generally base type fuzes are used. Such fuzes detonates the main charge in shell from base of shell to get desired penetration at target end by Hollow Charge Principle. Fuze FFV 651 is a base type fuze used in 84 mm HEAT amn. This fuze also can be classified as Electro Mechanical Fuze.
The sub assemblies/Components of fuze are manufactured at OFAJ/Trade. The final assembly of fuze is carried out at OF Khamaria. The various test/proof facilities have been created at OF Khamaria/ LPR Khamaria.
2. CONSTRUCTION
OF FUZE FFV 651
Fuze consists of components
such as Base Screw, Fuze Base,
Rotor & Rotor Assy/Detonator N8C,
Booster Charge/Magazine charge &
Complete Electric System.
The fig. Shows the details:-
ASSEMBLY OF FUZE FFV 651
SD ASSY
Deto. N8C
The following fig. Shows the position of the fuze in shell assembly:-
FUZE FFV 651
FUZE FFV 651 FUNCTIONINGThe function of the fuze is explained in the following fig.:-
On firing due to set back forces the two safety pins get compressed rear wards which allows two balls to fall out. This releases the safety plunger which moves rear wards. Now, rotor is free to rotate. The arming spring now rotates the rotor . The movement of the rotor is controlled by the escapement. Due to 3/4th rotation of rotor the detonator is in chain of explosive train. Now the fuze is in armed condition.
On impact on hard target, the piezo crystal get crushed against the wall of base screw generating voltage.The high voltage produced creates spark & detonates the detonator which further detonates the booster charge & further themagazine & the main bursting charge.
(IMPORTANCE OF FOURLAYER DIODE )
VARIOUS TESTS ON FUZE FFV 651
X – ray testing of empty fuze to confirm non arming condition of fuze
and existence of arming. Spring , Electric Deto. Electric, Leads
between Crystal & Cap, Spring Washers, Crystal assy
Base Screw & Fuze Base – Pressure testing
Resistance Test - 60 – 350 kΩ.
Fictional Tests- Non arming, Arming, Sealing, Function at low Temp.
Tests on detonator / Complete Electric system
TESTES ON DETONATOR N8C The detonator shall function within temp. range of +60º C to – 40 º C.
The surface quality of the deto. Shall be free from scraches, dents and burrs. AQL 1.0%.
The resistance between pole & body should be between 90 ± 30 Ω. AQL 1.0%.
The deto. should not be initiated by vol. Of 10 V ± 0.5 V. (AQL 0.65%)
Function : After storage at high (+71º C) & low temp. (-40 º C), the
resistance between poles of dto shall be 60 to 250Ω. The functioning time should be 10 µsec.
Blast Effect – A steel plate 5 mm thick should have a blind hole of Dia.
2.5 mm & min depth 0.60 mm after deto. is made to function by applying vol. 100V.
Shock Test - Deto. should not function by acceleration stresses of 30000 g.
TESTS ON COMPETE ELETRIC SYSTEM
Electrical parameter tests at -40ºC & +60ºC & ambient temp.- 8 parameter tests (Capacitance, Resistance, polarity of crystal, switching vol, leakage current,forward vol, holding current,leakage current of diode
Vibration test at -40ºC & +60ºC & ambient temp. – Electric tests afar vibration test.
Jolt Test - Electric tests afar vibration test.
Temperature cycling Test at +72ºC to -54 ºC - Electric tests afar jolt test.
Shock Test/Recovery proof – To confirm withsstanding of firing stresses..
Sensitivity Proof – To confirm functioning of four layer diode.
Plate proof – To confirm functioning of CES.