scholarly journals Multi-stage magnetic-fluid seals for operating in water – life test procedure, test stand and research results

2012 ◽  
Vol 19 (4) ◽  
pp. 62-70 ◽  
Author(s):  
Leszek Matuszewski
Keyword(s):  
Magnetic Fluid ◽  
Test Procedure ◽  
Limited Range ◽  
Test Stand ◽  
Technological Problem ◽  
Motion Velocity ◽  
Test Procedures ◽  
Rotating Shaft ◽  
Limited Range Of Motion ◽  
Multi Stage

ABSTRACTThe edge criteria for magnetic-fluid seals durability research are critical for the seal’stechnological usefulness. The magnetic fluid seal technology in water is much moredifficult technological problem in comparison to gas or vacuum environment. There isalways problem with immediate contact between magnetic fluid and the environmentaluninspected liquids. In the paper are presented ways of experiments definitions carried outwith multi-stage rotating magnetic fluid seal operating in permanent contact with utilitywater. The special test procedures have been elaborated and practically used, with theaim to define main characteristics of magnetic fluid seals. These characteristics were: critical pressure,critical motion velocity and working life of the seal. Some grades of commercial, silicon based magneticfluids of hydrophobic properties were tested in sealing system. The test stand and its features as well asresults of tests are presented in the form of tables, cross section draws and diagrams. In conclusion onecan see that multi-stage magnetic-fluid seals could be efficiently used in water for rotating shaft seals ina limited range of motion velocity and work lasting.

scholarly journals Multi-stage magnetic-fluid seals for operating in water – life test procedure, test stand and research results

2013 ◽  
Vol 20 (1) ◽  
pp. 39-47 ◽  
Author(s):  
Leszek Matuszewski
Keyword(s):  
Magnetic Fluid ◽  
Test Procedure ◽  
Limited Range ◽  
Motion Velocity ◽  
Rotating Shaft ◽  
Limited Range Of Motion ◽  
Multi Stage ◽  
Additional Control ◽  
Shaft Seals ◽  
Repeated Test

AbstractThe edge criteria for magnetic-fluid seals durability research were described in previous article [24] and now the tests results are presented. The tests were made with three magnetic fluids using various magnets quantity in magnetic assemblies. If values obtained in the repeated test deviated by more than 10 % from results of the first test an additional control test was made for final characteristics. The characteristics are: critical pressure, critical motion velocity and working life of the seal. The test stands were prepared for particular seals dimensions and results of tests are presented in the form of tables, cross section draws and diagrams. In conclusion one can see that multi-stage magnetic-fluid seals could be efficiently used in water for rotating shaft seals in a limited range of motion velocity and cycles quantity. Nevertheless a particular applications can be provided by magnetic-fluid seals only.

Investigation of Dynamic Magnetic Fluid Seal Wear Process in Utility Water Environment

2011 ◽  
Vol 490 ◽  
pp. 143-155 ◽  
Author(s):  
Zbigniew Szydło ◽  
Marcin Szczech
Keyword(s):  
Magnetic Fluid ◽  
Direct Contact ◽  
Magnetic Fluids ◽  
Mechanical Seals ◽  
Motion Velocity ◽  
Test Procedures ◽  
Rotating Shaft ◽  
Protection Measures ◽  
Liquid Environment ◽  
Wear Process

Serious problems arise when the magnetic fluid seal technology is needed to use in assemblies working in water or other liquid environment. Some efforts have been up to time made to design hybrid, two stage sealing structures with shields or mechanical seals used as protection measures to the magnetic fluid seal. Anyway, earlier or later there is always problem with direct contact between magnetic fluid and the environmental liquid. In the paper are presented results of experiments carried out with one stage rotating magnetic fluid seal operating in an direct contact with utility water. The special test procedures have been elaborated and practically used, with the aim to define main characteristics of magnetic fluid seals and to simplify experiments. These characteristics were: critical pressure,critical motion velocityandworking lifeof the seal. Four grades of commercial, silicon based magnetic fluids of hydrophobic properties were tested in a single stage sealing system. The results of tests are presented in the form of tables and diagrams. It is concluded that hydrophobic commercial magnetic fluids could be efficiently used in rotating shaft seals however within limited and rather low range of motion velocity.

scholarly journals Development of a New Testing Approach for Decentralised Technical Sustainable Drainage Systems

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 722
Author(s):  
Johannes Wolfgang Neupert ◽  
Philipp Lau ◽  
Daniel Venghaus ◽  
Matthias Barjenbruch
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Test Procedure ◽  
Test Stand ◽  
Test Substance ◽  
Test Procedures ◽  
Drainage Systems ◽  
Sustainable Drainage Systems

A part of the sustainable drainage systems (SuDS) are used to treat stormwater and must be tested for their hydraulic performance and the removal efficiency to assess serviceability and retention of the pollutants efficacy for in situ use. Current test procedures provide a good basis for laboratory testing SuDS on the test stand. However, the evaluation is not sufficiently representative to compare different SuDS with each other or for in situ use. The individual steps and specifications of an applied test procedure in Germany were considered and evaluation and optimizations for the test substance and sampling methodology of SuDS on the test stand were proposed. A comparison of the particle size distribution of the test substance Millisil W4 currently in use and total suspended solids of real road runoff was made, which showed that the presented test substance of real road-deposited sediments (RDS) provides a better reference for the test conditions and they could be the basis for more representative test methods. A particle size distribution was proposed for this new test substance. Furthermore, two methods of sampling were compared, which showed that a full flow sampling is preferable to a discrete sample. At the same time, it was shown that a separation limit of 20 µm is sufficient for the determination of TSS63.

Impairment Tutorial: Rating Tears of the Acetabular Labrum

2006 ◽  
Vol 11 (6) ◽  
pp. 4-7
Author(s):  
Charles N. Brooks ◽  
Richard E. Strain ◽  
James B. Talmage
Keyword(s):  
Magnetic Resonance ◽  
Hip Arthroscopy ◽  
Age Groups ◽  
Limited Range ◽  
Labral Repair ◽  
X Rays ◽  
Joint Stability ◽  
Acetabular Labrum ◽  
Complete Excision ◽  
Limited Range Of Motion

Abstract The primary function of the acetabular labrum, like that of the glenoid, is to deepen the socket and improve joint stability. Tears of the acetabular labrum are common in older adults but occur in all age groups and with equal frequency in males and females. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, is silent about rating tears, partial or complete excision, or repair of the acetabular labrum. Provocative tests to detect acetabular labrum tears involve hip flexion and rotation; all rely on production of pain in the groin (typically), clicking, and/or locking with passive or active hip motions. Diagnostic tests or procedures rely on x-rays, conventional arthrography, computerized tomography, magnetic resonance imaging (MRI), magnetic resonance arthrography (MRA), and hip arthroscopy. Hip arthroscopy is the gold standard for diagnosis but is the most invasive and most likely to result in complications, and MRA is about three times more sensitive and accurate in detecting acetabular labral tears than MRI alone. Surgical treatment for acetabular labrum tears usually consists of arthroscopic debridement; results tend to be better in younger patients. In general, an acetabular labral tear, partial labrectomy, or labral repair warrants a rating of 2% lower extremity impairment. Evaluators should avoid double dipping (eg, using both a Diagnosis-related estimates and limited range-of-motion tests).

Reliability of Laboratory Tests for the Control of Oral Anticoagulation

1974 ◽  
Vol 32 (02/03) ◽  
pp. 483-491
Author(s):  
E. A Loeliger ◽  
M. J Boekhout-Mussert ◽  
L. P van Halem-Visser ◽  
J. D. E Habbema ◽  
H de Jonge
Keyword(s):  
Human Brain ◽  
Laboratory Tests ◽  
Test Procedure ◽  
Rabbit Brain ◽  
Normal Range ◽  
Test Procedures ◽  
Discrimination Power ◽  
Power Of The Test ◽  
Assay Procedure ◽  
Low Sensitivity

SummaryThe present study concerned the reproducibility of the so-called prothrombin time as assessed with a series of more commonly used modifications of the Quick’s onestage assay procedure, i.e. the British comparative reagent, homemade human brain thromboplastin, Simplastin, Simplastin A, and Thrombotest. All five procedures were tested manually on pooled lyophilized normal and patients’ plasmas. In addition, Simplastin A and Thrombotest were investigated semiautomatically on individual freshly prepared patients’ plasmas. From the results obtained, the following conclusions may be drawn :The reproducibility of results obtained with manual reading on lyophilized plasmas is satisfactory for all five test procedures. For Simplastin, the reproducibility of values in the range of insufficient anticoagulation is relatively low due to the low discrimination power of the test procedure in the near-normal range (so-called low sensitivity of rabbit brain thromboplastins). The reproducibility of Thrombotest excels as a consequence of its particularly easily discerned coagulation endpoint.The reproducibility of Thrombotest, when tested on freshly prepared plasmas using Schnitger’s semiautomatic coagulometer (a fibrinometer-liJce apparatus), is no longer superior to that of Simplastin A.The constant of proportionality between the coagulation times formed with Simplastin A and Thrombotest was estimated at 0.64.Reconstituted Thrombotest is stable for 24 hours when stored at 4° C, whereas reconstituted Simplastin A is not.The Simplastin A method and Thrombotest seem to be equally sensitive to “activation” of blood coagulation upon storage.

The Correlation of the Limitations of Movement of the Shoulder Joint with the Functional Ability of Frozen Shoulder Patients at the Medical Rehabilitation Institute Dr. Mohammad Hoesin Palembang

2020 ◽  
Vol 3 (3) ◽  
pp. 88-96
Author(s):  
Ine Sintia ◽  
Nyimas Fatimah
Keyword(s):  
Functional Ability ◽  
Shoulder Joint ◽  
Frozen Shoulder ◽  
Limited Range ◽  
Medical Rehabilitation ◽  
Cross Sectional ◽  
Shoulder Joints ◽  
Limited Range Of Motion ◽  
Active Flexion ◽  
Cross Sectional Design

Background: Frozen shoulder is a condition of the shoulder joint that experiences inflammation, pain, adhesions, atrophyand shortening of the joint capsule resulting in limited motion. In frozen shoulder patients, the limited range of motion ofthe shoulder joint can affect and reduce functional ability. This study aims to analyze the correlation between the limitedarea of motion of the shoulder joint with the functional ability of frozen shoulder patients at the Medical RehabilitationInstallation Dr. Mohammad Hoesin Palembang. Methods: This study was an observational analytic study, correlationtest, with a cross sectional design. There were 29 frozen shoulder patients who met the inclusion criteria in the MedicalRehabilitation Installation Dr. Mohammad Hoesin Palembang in November 2018 was taken as a sample using consecutivesampling techniques. Functional ability was assessed using the quickDASH questionnaire and the area of motion wasmeasured using a goniometer, then analyzed. Results: The results of the correlation test showed significant resultsbetween functional abilities and the area of motion of the shoulder joints. Active flexion (p = 0.000; r = -0.669), activeextension (p = 0.004; r = -0.520), active abduction (p = 0.000; r = -0.663), active adduction (p = 0.022; r = -0.423 ), passiveflexion (p = 0.001; r = -0.589), passive extension (p = 0.002; r = -0.543), passive abduction (p = 0.000; r = -0.676), passiveadduction (p = 0.038; r = -0.388). Conclusion: There is a significant correlation between limited joint motion andfunctional ability in frozen shoulder patients at the Medical Rehabilitation Installation of Dr. Mohammad HoesinPalembang

P080 Acroosteolysis: a rare complication or a co-occurrence with Juvenile Idiopathic Arthritis?

Rheumatology ◽  
2021 ◽  
Vol 60 (Supplement_5) ◽  
Author(s):  
Makhlouf Yasmine ◽  
Miladi Saoussen ◽  
Fazaa Alia ◽  
Sellami Mariem ◽  
Souabni Leila ◽  
...  
Keyword(s):  
Juvenile Idiopathic Arthritis ◽  
Psoriatic Arthritis ◽  
Rare Complication ◽  
Plain Radiograph ◽  
Limited Range ◽  
Acute Phase Reactants ◽  
Limited Range Of Motion ◽  
Macular Rash ◽  
Oligoarticular Juvenile Idiopathic Arthritis ◽  
Dysmorphic Syndrome

Abstract Background Acroosteolysis refers to a destructive process involving the distal phalanges of the fingers and toes that may extend to metacarpals or metatarsals. Rarely idiopathic, the diagnosis of primary acroosteolysis requires ruling out other causes. Juvenile idiopathic arthritis is an exceptional aetiology of acroosteolysis occurring mainly in psoriatic arthritis. Here by a case of juvenile idiopathic arthritis associated with acroosteolysis of the toes. Methods A 13-year-old girl with no past medical history, presented to our department of rheumatology with oligoarthritis affecting both wrists and knees. She had no familiar history of psoriasis nor rheumatic diseases. She described a dull ache and recurring swelling of knees evolving for >6 years associated with a macular rash of the chest without fever. On examination, the knees were swollen with a limited range of motion of < 90°. Examination of the spine and sacroiliac joints was unremarkable. There was no deformity, no dysmorphic syndrome nor ligamentous hyper laxity. The mucocutaneous examination was normal. Similarly, there was no hepatosplenomegaly or swollen lymph nodes. Laboratory investigations showed high acute phase reactants and normal blood count. Rheumatoid factor, anti-cyclic citrullinated peptide antibodies and antinuclear antibodies were also negative. Besides, she was negative for HLAB-27. Ophthalmic examination did not show any sequelae of uveitis. Results Plain radiograph of the feet revealed bone resorption of the second and fifth distal phalanges without signs of reconstruction. Other secondary causes of acroosteolysis were ruled out. The diagnosis of oligoarticular juvenile idiopathic arthritis was made. In view of the involvement of the distal phalanges, the phenotype of psoriatic arthritis was probable. The patient was initially treated with non-steroidal anti-inflammatory drugs as well as intraarticular injections of corticosteroids in knees. As the flares persisted, she was put on Methotrexate at a dosage of 15 mg per week with marked clinical improvement. Conclusion Our case illustrates a possible occurrence of acroosteolysis of the feet in the field of an active juvenile idiopathic arthritis. It is important to rule out other causes and make a rapid diagnosis in order to ensure appropriate management decisions.

scholarly journals Surgical Treatment for Malunion of the Lateral Humeral Epicondyle with Posterior Subluxation of the Radial Head: A Case Report and Literature Review

2018 ◽  
Vol 2018 ◽  
pp. 1-4
Author(s):  
Koichi Yano ◽  
Yasunori Kaneshiro ◽  
Hideki Sakanaka
Keyword(s):  
Lateral Collateral Ligament ◽  
High Energy ◽  
Limited Range ◽  
Forearm Rotation ◽  
Collateral Ligament ◽  
Lateral Epicondyle ◽  
Limited Range Of Motion ◽  
Contracture Release ◽  
Normal Congruence ◽  
The Right

A 24-year-old right-handed man suffered right olecranon and lateral epicondylar fracture from high energy trauma. Fixation of olecranon was performed by a previous doctor. Three months after operation, he presented with limited range of motion (ROM) of the right elbow caused by malunion of the lateral epicondylar fracture and subluxation of the radiohumeral joint. Preoperative ROM of the right elbow was flexion 110° and extension −75°. Forearm rotation was pronation 85° and supination 65°. Fragment excision of the lateral epicondyle, which was 27 mm in length, and lateral collateral ligament repair using anchors were performed. Fourteen months postoperatively, contracture release of the elbow was performed. Twenty-four months postoperatively, radiograph of the elbow showed normal congruence without osteoarthritic changes and the ROM of the right elbow was flexion 120° and extension −35°. Forearm rotation was pronation 90° and supination 70°. In the surgical setting, in case of the size of the lateral epicondylar fragment is relatively large, the fragment should be fixed or lateral collateral ligament should be repaired when the instability of the elbow is found.

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