Process Control System

PROCESS CONTROL SYSTEM

Prior to cutting the material which may be in from or pipes plate rod forgings billets etc The batch number is transferred on every piece which may be cut from parent material after forgings each piece is re-stamped if batch number is not visible.

HEAT TREATMENT

Heat treatment is done on all material as per requirement of applicable specification heat treatment is done on material on the basis of each LOT defined as all fittings of same size type &wall thickness manufactured from one heat of material a test coupon is also heat treated along with the material for each lot / batch.

The heat treatment furnace is fitted with thermocouples and temperature recorder for getting an accurate record of time temperature graph for analysis the thermocouples are periodically calibrated by reputed inspection agency / calibration house.

A complete record of time temperature graph is maintained in record for reference.

TESTING

A) TENSILE TEST :

Tensile test is done on a test coupon / on sample drawn from fitting or starting material in accordance with specification as required by purchaser all testing is done in third party approved labs and physical report of product incorporated in material certificates issued to the clients.

B) HARDNESS TEST :

Hardness testing is carried out per lot / batch as per sample technique (10% materials from each heat treatment batch) A in house hardness machine is available which is being calibrated periodically by calibration agency. The results obtained are recorded and used for certification.

C) IMPACT TEST :

Impact test is done on those materials confirming to A420 and A350 as required by the code sample From each batch of material are tested for their impact properties at the temperature as specified by The code. The procedure for testing is done as per A370.

D) SUPPLEMENTARY TEST :

Any supplementary test in addition to code is carried out if specified in purchase order by the Purchaser such as corrosion test magnetic particle test and ultrasonic test.

MACHINING AND DIMENSIONAL CONTROL

Machining is carried out as per required dimensional specification Adequate templates and fixtures are maintained to guide the dimensions required Accurate measuring instruments used to check various dimension during the machining GO and NOGO gauges are used to check the ID & OD of fittings. Fittings are then debarred. Threaded fittings are checked with the help of thread gauge.

All template fixtures and gauges are regularly checked to ascertain that are dimensional stable.

FINISHING

All fitting are cleaned to remove any surface scale during heat treatment. All stainless steel fitting are pickled and passivated. A proper concentrate of solution is maintained fittings are then coated with rust preventive for protection against corrosion.

MARKING

The fittings are inspected for various dimensions and are then stamped for required specification heat number / batch number is also stamped again if it is not visible.

CERTIFICATION

The fitting are supplied along with the manufacturer certificate which incorporate following details :

1. Materials Description
2. Chemical Analysis (heat / product) 3. Tensile test
4. Hardness value
5. Type of heat treatment
6. Dimensional standards
7. Material specification
8. Impact Value for low temp items

GENERAL NOTE

The quality assurance plan as documented here is an abridged version. The programmer is pursued to achieve desired quality levels detail document and data is maintained can be reviewed by customer engineer on request. This programme is upgraded as and when require and change in the technical specification of applicable code.