System Study: High-Pressure Coolant Injection 1998–2018

The purpose of this paper is to discuss the thermal hydraulic behavior and related dynamic response of the Dresden Unit 3 HPCI (High Pressure Coolant Injection) Injection piping. A hydraulic transient occurred on the HPCI injection line piping, that resulted in damge to piping support, pulling the anchors out of the wall. The ensuing investigation following the discovery of the failed support suspected a possible waterhammer event, but walkdowns of the system did not provide much evidence of a propagating disturbance in the system. A review of plant data subsequent to the July 5, 2001 trip showed that during an automatic HPCI injection initiation, a pressure transient occurred, with the potential to produce loads on the piping and supports in excess of their designed capacity. The ensuing investigation determined that non-condensable was present at two locations within the system. It was also determined that the temperatures of the piping downstream of the HPCI injection valve were sufficiently high to introduce some amount of steam to the upper portions of the HPCI line during the time interval between the injection valve opening and the HPCI pump reaching pressure. This paper will discuss the analytical work performed to investigate this transient, along with the piping forces calculated for various scenarios considered.

Heat and fluid flow in accident of Fukushima Daiichi Nuclear Power Plant, Unit 3 (Behaviour of high pressure coolant injection system (HPCI) based on thermodynamic model)

Transactions of the JSME (in Japanese) ◽

10.1299/transjsme.2014tep0155 ◽

2014 ◽

Vol 80 (814) ◽

pp. TEP0155-TEP0155 ◽

Cited By ~ 1

Author(s):

Shigenao MARUYAMA

Keyword(s):

High Pressure ◽

Fluid Flow ◽

Power Plant ◽

Nuclear Power ◽

Injection System ◽

Coolant Injection ◽

Fukushima Daiichi ◽

Heat And Fluid Flow ◽

High Pressure Coolant ◽

Nuclear Power Plant Unit

PERFORMANCE OF HIGH PRESSURE COOLANT ON TOOL WEAR

International Journal of Research in Engineering and Technology ◽

10.15623/ijret.2013.0211011 ◽

2013 ◽

Vol 02 (11) ◽

pp. 61-65 ◽

Cited By ~ 2

Author(s):

R.A. Patil .

Keyword(s):

High Pressure ◽

Tool Wear ◽

High Pressure Coolant

High Stock Removal Hard Turning of Hardened 52100 Steel with High-Pressure Coolant Applied

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1063/1/012006 ◽

2021 ◽

Vol 1063 (1) ◽

pp. 012006

Author(s):

Xiaozhong Song ◽

Roman Dreussi ◽

Rahul G. Chaudhari

Keyword(s):

High Pressure ◽

Hard Turning ◽

Stock Removal ◽

High Pressure Coolant

Experimental Study of tool Wear Mechanisms in Conventional and High Pressure Coolant Assisted Machining of Titanium Alloy Ti17

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.554-557.1961 ◽

2013 ◽

Vol 554-557 ◽

pp. 1961-1966 ◽

Cited By ~ 3

Author(s):

Yessine Ayed ◽

Guenael Germain ◽

Amine Ammar ◽

Benoit Furet

Keyword(s):

High Pressure ◽

Titanium Alloy ◽

Tool Wear ◽

Titanium Alloys ◽

Tool Life ◽

Wear Mechanisms ◽

Cutting Forces ◽

Cutting Edge ◽

Rake Face ◽

High Pressure Coolant

Titanium alloys are known for their excellent mechanical properties, especially at high temperature. But this specificity of titanium alloys can cause high cutting forces as well as a significant release of heat that may entail a rapid wear of the cutting tool. To cope with these problems, research has been taken in several directions. One of these is the development of assistances for machining. In this study, we investigate the high pressure coolant assisted machining of titanium alloy Ti17. High pressure coolant consists of projecting a jet of water between the rake face of the tool and the chip. The efficiency of the process depends on the choice of the operating parameters of machining and the parameters of the water jet such as its pressure and its diameter. The use of this type of assistance improves chip breaking and increases tool life. Indeed, the machining of titanium alloys is generally accompanied by rapid wear of cutting tools, especially in rough machining. The work done focuses on the wear of uncoated tungsten carbide tools during machining of Ti17. Rough and finish machining in conventional and in high pressure coolant assistance conditions were tested. Different techniques were used in order to explain the mechanisms of wear. These tests are accompanied by measurement of cutting forces, surface roughness and tool wear. The Energy-dispersive X-ray spectroscopy (EDS) analysis technique made it possible to draw the distribution maps of alloying elements on the tool rake face. An area of material deposition on the rake face, characterized by a high concentration of titanium, was noticed. The width of this area and the concentration of titanium decreases in proportion with the increasing pressure of the coolant. The study showed that the wear mechanisms with and without high pressure coolant assistance are different. In fact, in the condition of conventional machining, temperature in the cutting zone becomes very high and, with lack of lubrication, the cutting edge deforms plastically and eventually collapses quickly. By contrast, in high pressure coolant assisted machining, this problem disappears and flank wear (VB) is stabilized at high pressure. The sudden rupture of the cutting edge observed under these conditions is due to the propagation of a notch and to the crater wear that appears at high pressure. Moreover, in rough condition, high pressure assistance made it possible to increase tool life by up to 400%.

Evaluation of Performance of Various Coolant Grades When Turning Ti-6Al-4V Alloy With Uncoated Carbide Tools Under High-Pressure Coolant Supplies

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4041778 ◽

2018 ◽

Vol 141 (1) ◽

Cited By ~ 2

Author(s):

Emmanuel O. Ezugwu ◽

Rosemar B. da Silva ◽

John Bonney ◽

Eder S. Costa ◽

Wisley F. Sales ◽

...

Keyword(s):

High Pressure ◽

Failure Modes ◽

Physical Damage ◽

Evaluation Of Performance ◽

Life Tool ◽

Resistance To Oxidation ◽

Tension Properties ◽

Almost All ◽

Coolant Delivery ◽

High Pressure Coolant

This work presents the evaluation of three commercially available coolant grades (dicyclohexylamine-based coolant, a triethanolamine-based coolant, and an ester-based coolant) when machining Ti-6Al-4V alloy with high-pressure coolant delivery. The evaluations were based on tool life, tool failure modes, surface integrity, and chip formation. The dicyclohexylamine-based coolant was the more effective coolant when machining at the highest pressure of 20.3 MPa due to its stability at elevated temperature, whereas the triethanolamine-based coolant performed effectively at a pressure of 11 MPa due to its low surface tension properties. Deterioration of the ester-based coolant was found in almost all coolant pressures due to its low resistance to oxidation. Surfaces generated when machining with all coolants grades were generally acceptable with negligible physical damage.