Influence of Novel Redirector with Bypass Damping on the Performance of Load-Sensing Steering System

Load-sensing steering systems for articulated loaders are prone to large pressure shocks and oscillations during steering operations, affecting the system stability. An optimized structure of the redirector with bypass damping is proposed to improve this phenomenon. In this structure, orifices and throttle grooves are added to the traditional redirector. To control the steering load and working conditions, the steering load of the loader is replaced by a pressure regulating valve. Simulation and experimental results reveal that the redirector with bypass damping has better load-sensing characteristics than the traditional redirector. The peak output pressure shock caused by the load unit step signal decreases from 6.50 to 5.64 MPa, which means the pressure oscillation of the hydraulic system is reduced by 13.4%. The pressure fluctuation time can be reduced from 2.09 to 1.6 s, with a decrease rate of 23.4%. The output pressure oscillation decays swiftly, and the smoothness of the steering operation is improved significantly.

Rigless Remote Intervention: A Case Study of Combo Unit Utilization in Mahakam Offshore East Kalimantan

Mahakam block has been producing for over 40 years and now is in declining phase. Daily drilling and well intervention operations are still actively carried out to sustain and prolong the natural decline curve. Efficiency measures are taken out in each and every aspect of operations to support the diminishing values. One of them is the reduction of offshore platform sizing. Future minimalist platforms have limited top deck space which will further be reduced by the prevalence of: 1. Fixed platform equipment (generators, crane, etc.), and 2. Hazardous area requirement for Zone 0, Zone 1, and Zone 2. The future minimalist platform has a deck space area of approximately 221 m2, not yet taken into account said the reduction factors. The presence of the hazardous area and fixed equipment can reduce the free deck space availability down to 20% from the total deck space. These platforms are not originally designed with well intervention work in mind. However, the past 40 years proves that well intervention should never be left out when extending well’s lifetime is the objective. Well intervention unit, depending on the intervention type, requires top deck space from 26 m2 up to 92 m2 of free space, and an additional 3-4 m2 for lifting, means such as mast unit if the platform does not have a crane. Moreover, in a remote intervention mode, where no supporting barge is present, space requirement above the top deck became crucial as there is no alternative to back load unit to the barge incase the top deck beingover crowded. To support the continuity of remote intervention being more efficient alternative to barge-supported operation, the well intervention team initiates the feasibility study using combo unit as a replacement for conventional slickline and electric line unit. There are three types of combo unit presented in this paper, 1. Split Combo Unit, 2. Combined Drum Combo Unit, and 3. Digital Slickline Combo Unit. These types of unit can reduce the deck space requirement by 30%, reducing number of personnel needed from eight (8) to five (5) personnel in a single shift, improving operation timing efficiency, and improves the contract administration aspect. Despite the seemingly positive results, there are still issues to be resolved, both technical and non-technical, for combo unit to be an all-rounder solution for wireline work. This paper shall provide an early level observation and analysis for the feasibility of combo unit as remote well intervention unit, starting from the methodology to the corresponding results and lesson learnt.

SAFETY OF TRANSPORT OPERATIONS PERFORMED USING PALLET LOAD UNITS

During transport operations, even under normal operating conditions, the loading unit is subject to inertial forces, which may cause deformation of the unit, and in extreme cases, its disintegration. Stretch film wrapping is the most commonly used method of securing a load unit. This paper presents a new simplified simulation model of a class A load unit, with a layered structure, secured with stretch film. Between the layers of packaging, stick-slip friction was applied. A method of estimating the containment force was also proposed. This model can be used to pre-determine the number of film layers necessary to ensure load stability. Simulations can reduce the amount of film used and the number of stability tests performed experimentally.

RE-DESIGN SISTEM DISTRIBUSI AIR BERSIH DAN FIRE HYDRANT DI GEDUNG PLN UP3B KALSELTENG

Sistem penyediaan dan distribusi air bersih di gedung-gedung bertingkat sering mengalami kendala. Tidak terkecuali PT. PLN (Persero) Gedung UP3B Kalselteng yang tidak luput dari permasalahan tersebut. Untuk itu perlu dilakukan perancangan ulang sistem distribusi dan penyediaan air bersih serta hidran kebakaran pada gedung. Tujuan dari penelitian ini antara lain menganalisis kebutuhan dan distribusi air bersih dan hidran kebakaran di dalam gedung. Kebutuhan air bersih dihitung berdasarkan jumlah penduduk yang mengkonsumsi air bersih, jenis dan jumlah unit beban alat perpipaan. Perhitungan head loss pada pipa menggunakan persamaan Hazen - William, Darcy-Weisbach dan Colebrook-White. Clean water supply and distribution systems in high-risk buildings often experience problems. No exception is the PT. PLN (Persero) UP3B Kalselteng Building which did not escape this problem. For this reason, it is necessary to re-design the distribution system and provide clean water and fire hydrants to the building. The objectives of this study include analyzing the needs and distribution of clean water and fire hydrants in the building. Clean water needs were calculated based on the number of people that consuming the clean water, the type and number of plumbing tools load unit. Calculation of head loss in pipes used Hazen – William, Darcy-Weisbach and Colebrook-White equation.Clean water supply and distribution systems in high rise buildings often experience problems. No exception is the PT. PLN (Persero) UP3B Kalselteng Building which did not escape this problem. For this reason, it is necessary to re-design the distribution system and provide clean water and fire hydrants to the building. The objectives of this study include analyzing the needs and distribution of clean water and fire hydrants in the building.Clean water needs was calculated based on the number of people that consuming the clean water, the type and number of plumbing tools load unit. Calculation of head loss in pipes used Hazen – William, Darcy-Weisbach and Colebrook-White equation.

PROPERTIES OF THE REACTIVE POWER OF THE ASYNCHRONOUS MACHINE AS A LOAD OF THE ELECTRIC NETWORK

It is known that the voltage mode of the electrical network is associated with the balance of reactive power and directly affects the operation of production equipment. A typical static characteristic of a power supply unit in terms of reactive power, obtained for a load composition characteristic of electrical networks, is an extreme function with a minimum point. It is the presence of a minimum point in the dependence of reactive power on voltage that makes it possible to develop this type of instability as a voltage avalanche. This mode is especially dangerous for industrial units with abruptly variable loads, which can create significant fluctuations in the supply voltage, which significantly affects the operation of powerful asynchronous motors. Therefore, the issues of the relationship between the parameters mode of the electrical network and the properties of electrical loads are always important, especially asynchronous machines as the main consumer of electricity, which largely determines the properties of the generalized reactive power curve of the entire load unit. Literary sources do not explain in detail why the curve of the dependence of the reactive power of the power supply unit on voltage has a minimum. The article sets out this issue in sufficient detail for asynchronous machines as the main consumer of reactive power in electrical networks. The task is to obtain the dependence of the reactive power of an induction machine with a squirrel-cage rotor on the voltage of the supply network, as well as to determine the criteria for controlling reactive power flows in order to inadmissibly reduce the voltage in the load unit. As a result, based on the system of equations of an asynchronous machine, the dependence of its reactive power on the supply voltage of the network was derived. The mathematical properties of this function are investigated with a physical justification of its unimodality and the presence of a minimum point. The obtained expressions make it possible to determine the magnitude of the control action on the high-speed reactive power compensation devices to stabilize the voltage level in the power supply unit.

Basis for the design of drive-in and drive-through racking

Drive-in and drive-through accumulation racking systems are recommended for great amounts of goods with few various units. According to the "First In, Last Out" - FILO and "First-In, First-Out" - FIFO principle, the palletized load unit are stored into deep tunnels accessible by forklift trucks for handling operations. This allows exploiting as much room as possible and eliminating the aisles traditionally required for manipulating purposes. This paper provides basic information on the requirements, design and use of drive-in and drive-through racking systems in accordance with current regulations and standards. Minimum required clearances and tolerances due to all influencing parameters for manually operated systems are discussed.

Pengujian Keselamatan Thermal pada Battery Pack Sepeda Motor Listrik Berdasarkan Regulasi UN R-136

The electric-motorcycle is one of the promising technology that can improve environmental quality as well as reduce dependency on oil imports in Indonesia. The major challenge of electric-motorcycle implementation is the safety of the lithium-ion battery pack. This research aims to ascertain the over-temperature protection, and also to carry out shock & cycling test for the battery thermal safety. The testing procedures and apparatus comply with the United Nations Regulation No 136 (UN R-136), namely a temperature humidity chamber, a battery load unit, a blower, and a charger. The first step is the designing and prototyping of the battery pack with 100 V and 30 Ah, which contains a module of cells, Battery Management System (BMS), wiring, isolator, socket, and aluminum casing. The second step is the battery thermal safety test. The results showed that the battery pack satisfied the acceptance criteria, with evidence of no electrolyte leakage, rupture, fire, and explosion during and after testing. Result of over-temperature protection, BMS can cut-off the discharge rate at a temperature of 45.89°C. Meanwhile, for thermal shock & cycling tests, the battery pack did not fail when the temperature changes from 59.72°C and -40.25°C for 60 hours.

Assessment of the Pallet Unit Load Stability by Simulation Methods

The paper presents a simulation model of a loading unit dynamics, with a layered structure, wrapped with a stretch film. Stretch film wrapping is the most commonly used and cheap method of securing the load unit. The model, proposed by the author, allows assessing the stability of the unit during the transport operations, when the loading unit is subjected to inertial forces. Deformations of a unit and prediction of its disintegration in extreme cases can be evaluated based on results of a simulation. The value of the necessary containment force as well as the number of wraps with the pre-stretched film, can also be estimated. In effect, simulations can reduce the amount of film used and the number of stability tests performed experimentally.

Investigation On The Influence of A Novel Redirector With By-Pass Damping On The Performance of Load Sensing Steering System

The load sensing steering system of articulated loaders is prone to large pressure shock and oscillation during steering operations, affecting the stability of the steering system. To improve this phenomenon, an optimized structure of the redirector with by-pass damping is proposed, which adding orifices and throttle grooves to the original redirector. In the study, to control the steering load and working conditions, the steering load of the loader is replaced by using a pressure regulating valve. The simulation and experimental results shows that, compared with the traditional redirector, using the novel structure redirector with by-pass damping ensures good load sensing characteristics, the peak output pressure shock caused by the load unit step signal decreases from 65.04bar to 56.35bar, with a decrease rate of 13.4%, reducing the pressure oscillation of the hydraulic system. The pressure fluctuation time can be reduced from 2.09s to 1.6s, with a decrease rate of 23.4%, the output pressure oscillation decays faster, the smoothness of the steering operation is significantly improved.