The tubes are heated to a temperature above the transformation range in the austenitizing furnace. This allows hardening or normalization to be carried out. Hardening occurs when the austenitized tube is rapidly cooled in an external water quench. The as-quenched tube has a particular hardness and microstructure. It is now ready for subsequent tempering. The hardened tube is heated in a tempering furnace, held at a specific temperature for a set period of time and air-cooled. This treatment establishes mechanical properties of the tube and is commonly referred to as "hardening and tempering" or "quenching and tempering".
Normalization occurs when the austenized tube is allowed to cool at ambient temperatures in still air. In such cases, the mechanical properties are dictated by the chemical properties of the steel. 

Hardening occurs when the austenitized tube is rapidly cooled in an external water quench. The as-quenched tube has a particular hardness and microstructure. It is now ready for subsequent tempering.

The hardened tube is heated in a tempering furnace, held at a specific temperature for a set period of time and air-cooled. This treatment establishes mechanical properties of the tube.

Once the tubes have been heat-treated, a rotary straightener straightens them. 

 After straightening, the tube body is exposed to nondestructive inspections using an automated, electromagnetic process. The ends of the tubes are inspected using wet fluorescence magnetic particles.

Flux Leakage Testing with Integrated Wall Thickness Testing: 

Magnetic Particle Inspection of Pipe Ends:

When requested, tubes can be furnished with upset ends. Kindberg can forge tubing and drill pipe upsets in accordance with API specifications. Special upsets for premium and integral connections can also be forged. 

Two – Upsetters:

Our ultrasonic inspection equipment is state-of-the-art technology. We inspect for longitudinal, transverse and oblique flaws on the internal and external surface. The wall thickness can also be inspected with 100 percent surface area coverage.  

Couplings are threaded female connectors used to assemble Oil Country Tubular Goods. voestalpine Tubulars has the largest automated coupling manufacturing facility in Western Europe. The coupling manufacturing process involves the following steps: Tubes referred to as coupling stock are cut into blanks by automated saws. The blanks are transported to the CNC threading machines, where threads are cut to stringent tolerances. Subsequently, the couplings are inspected, nondestructively tested, phosphatized and, color-coded according to applicable specifications. Finally, they are torqued onto the tubes during the tube threading operations.

The coupling stock is cut into coupling blanks using four CNC cut-off machines.

Couplings are produced for API and premium threads on a total of 9 threaders.

The couplings are subjected to visual inspections under UV light for longitudinal and transverse flaws.

Two – Units installed in parallel

Phosphating involves applying an 8 – 10 µm (0.315 – 0.394 mils) zinc phosphate layer to the coupling threads. This provides temporary protection against corrosion and improves galling resistance.

A total of 8 CNC threading machines; making up four threading lines, are used to cut API threaded connections or premium threaded connections with meticulous precision. After a methodical thread inspection the couplings are made-up power tight. Then the tubes are filled with a water/oil emulsion and an appropriate hydrostatic pressure test is performed.

Threaders:

Sizing Press:

Für die Herstellung spezieller Gewindeverbindungen können auf dieser Anlage die Rohre auf einer Länge von 100 mm kalibriert werden.

Coupling Buck-On Machine

The coupling buck-on machine is used to apply the coupling power tight. The torque required in based on the thread profile, the grade and dimension of the material. 
 

Pipes are filled with a 3% water/oil emulsion. The appropriate test pressure is then applied and held for a specified time. The pressure and time requirements are based on the dimensions, grade and thread profile or customer requirements.

 Four - Hydrostatic Testers:

Hydrostatic Tester for Pup Joints:

During API checking, the pipes are weighed and measured. The pipes and couplings are stamped with identifying markings. Production, specification and order-related markings are paint stenciled along the body of the pipe.

Systems:
Length Measuring Device
Manufacturer: WALLICH & KRÖGER

Length Measuring Device
Manufacturer: WALLICH & KRÖGER

Pipe Weighing Equipment
Manufacturer: WALLICH & KRÖGER

Radial Die-Stamping Equipment
Manufacturer: WALLICH & KRÖGER

Pipe Stenciling Equipment (REA-JET)
Manufacturer: WOLF SIGNIERTECHNIK

These systems apply a temporary corrosion- resistant coating to the outer surface of the pipes.

Pipes are packaged in 2-4 ton bundles using up to 8 steel straps. Packaging data (e.g. weight, number of pipes) are printed on the bundle tags. The bundles are then sent to the shipping department.