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Bengbu Longhua Die Casting Machine Co., Ltd. releases professional technical guidelines on speed and pressure matching for precision die casting production, effectively solving common quality defects of thin-walled and thick-walled castings and optimizing the overall performance of die casting machine production. Compactness is the core standard for judging casting quality, and reasonable speed and pressure configuration is the key to stable production of high-quality die casting equipment. There are differentiated process logics for thin-walled and thick-walled die-cast parts. For thin-walled castings with high surface finish requirements, a fast injection velocity is essential, and conventional die casting machinery speed parameters can basically meet production standards. In contrast, thick-walled castings require both excellent surface quality and internal compactness, which cannot be satisfied by simple high-speed injection alone. After the two-speed nitrogen cylinder explosive injection, traditional machines often suffer from insufficient pressure supplement, resulting in loose internal casting structure and defective products. Speed and pressure present an inverse proportional relationship in die casting production, similar to vehicle gear operation: low speed delivers strong pressure, while high speed reduces thrust. To address the pain point of insufficient pressure for thick-walled parts, Longhua’s technical team has upgraded the independent supercharging function for its die casting machine. The optimized equipment balances injection speed and supercharging force, greatly improving the internal compactness of thick-walled castings and effectively making up for shrinkage holes and sprue sand holes caused by uncontrolled mold temperature. Professional equipment, high-precision molds and skilled operators are the three core elements of high-yield die casting production. The optimized speed and pressure matching technology perfectly adapts to diverse production demands of different wall-thickness castings, minimizes product defects, and helps global manufacturing enterprises achieve stable, efficient and high-quality intelligent die casting production.

Bengbu LongHua Die Casting Machine Co., Ltd. has released standardized operational and maintenance specifications for die casting molds, delivering professional guidelines for safe and stable mass production with die casting machines. Standardized mold operation and daily maintenance are core foundations to avoid mold damage, reduce downtime, and improve the yield of precision die-cast products in industrial manufacturing. Before formal mold production, operators must follow strict pre-production rules.  1.Under cold mold conditions, shift handover or abnormal equipment status, workers need to reset switches and disable secondary injection and pressurization functions to prevent machine collision and die casting mold damage.  2.All casting residues and waste materials must be fully dried before putting into the crucible to avoid molten aluminum splashing and safety accidents.  3.Every die casting machine must be started with inching inspection, ensuring normal hydraulic oil temperature, lubrication and cooling water operation before formal production. In daily die casting production, standardized process control is essential, including professional mold spraying, sliding part oil brushing, and thorough cleaning of aluminum slag and foreign matters on parting surfaces. Operators must strictly control material temperature and mold temperature via mold temperature machines and cooling systems, and adjust handle thickness and process parameters according to product quality conditions. For long-term service life of die casting molds, workers must clean cavity surfaces, exhaust slots and overflow tanks regularly with air guns or copper rods instead of hard tools to avoid cavity scratches. Regular mold cleaning with professional oil agents removes corrosive compounds, prevents surface dulling and ensures stable casting quality. Besides, it is necessary to fasten mold components, check slider limits and record product quality regularly, realizing scientific full-lifecycle die casting mold maintenance and maximizing production efficiency.

1. Basic Operation Standards for Cold Mold Startup The mold in the cold mold state, to brush more oil, less spray. When the mold temperature reaches the technical requirements after the normal spray coating. Then the two blocks and pressurized gradually open, and according to the normal process of production. 2.Low-Pressure Pre-Production Debugging Process Mold in the case of no preheating to low-pressure production, and the production parameters on the machine must be reduced or closed to zero (remember: do not open fast injection to prevent mold run and stick).Every production of a mold to brush the oil or demoulding paste, to prevent the cold mold adhesion with material phenomenon (aluminum temperature had better reach 680℃ above, so the mold temperature rise faster).Low pressure production of about 30 molds, with the exhaust device and injection in each mold to close the exhaust valve in time, at the same time to observe the normal operation of the active parts, and then debug the production parameters of the machine until the production of qualified products and extraction of finished products.In the die casting production, it is found that the gate and the casting parts have the phenomenon of aluminum sticking pull caused by impact.If there is running material, should be cleaned up in time, otherwise the more tight the pressure, the more difficult to clean up. 3. Cold Mold Production Inspection & Formal Production Switching Standards After completing low-pressure trial production and parameter debugging, conduct comprehensive inspection on casting appearance, internal porosity and surface finish. Operators need to continuously monitor mold temperature changes and keep the release agent coating uniform and moderate to avoid insufficient lubrication or residual oil gas defects. When the mold temperature is stable within the standard production range, no sticking aluminum, flash, pulling and other abnormal defects appear in continuous 50 qualified castings, and all mechanical moving parts operate smoothly without jitter or stalling, the production line can be officially switched to normal high-efficiency mass production mode.

The correct preheat production plan of the mold 1.If the die casting mold needs to be preheated before production, the cooling water of the mold shall be temporarily closed, and then the water volume shall be gradually adjusted according to the mold temperature. When preheating the mold, be careful not to make the mold local overheating (dark red phenomenon), in case the mold annealing. 2.When preheating the mold, it is forbidden to use two-block injection or pressurized injection.It must be heated effectively without damaging the mold according to the design requirements of the mold.For those with thermostatic tubing, use a mold temperature controller for heat preservation and heating.If there is no thermostatic tubing, gas can be used to increase the temperature. When heating, it should be done gently, evenly and slowly so that the temperature rise of the core and the core seat can be synchronized with the expansion.When the mold temperature preheats to about 220°, run each moving part to prevent the normal operation from being affected by the phenomenon of tight biting due to thermal expansion.After producing about 10 molds at low pressure, the high pressure production parameters were adjusted and qualified products were extracted.In the early stage of die casting production, it was found that the sprue part and the casting part of the finished product had the phenomenon of aluminum sticking pull caused by impact.If there is running material, should be cleaned up in time, otherwise the more tight the pressure, the more difficult to clean up.

Mold use and maintenance manual After the acceptance of the mold, in order to make the mold to maintain the best performance state and prolong the service life, to ensure the normal production and product quality, to reduce the production cost as far as possible, when the mold is used, please follow the following items for necessary maintenance and maintenance. Mold production specification Inspection and installation requirements before mold production Before starting work, you must wear protective equipment, such as hard hat, work clothes and labor protection shoes. Wearing short-sleeved shirts, shorts and slippers is strictly prohibited. Before the installation of the mold, first of all to confirm the die casting machine specifications and mold design requirements to match. The die caster must have a thorough knowledge of the mold structure, including: Check whether the mould has core pulling (dynamic mould core pulling, static mould core pulling, oblique rod core pulling and hydraulic core pulling).         Whether it is necessary to install the pre-reset pull rod or strong spring of the ejector rod. Check whether the combination size of sprue sleeve, flange and melting cup is consistent. Confirm if it is the center sprue. Check the top bar position for no interference and ejection balance. Replace the molten cup punch according to the mold condition and adjust the injection lifting mechanism when necessary. Check the outer fastening bolt of the mold again, and confirm that there is no loosening phenomenon, the mold can be installed on the machine to ensure reliable installation of the mold. Check the die casting machine and mold moving template and static template mounting surface: no foreign body, no high point. Mould in die casting machine, to the right after tighten-up platen and installation is firm, and then to idle mode of the mould, check whether mold opening and closing smoothly and observe its each part movement is flexible, whether there are abnormal phenomenon, the ejection stroke, open schedule is in place, it fits the profile at the closing time, closely linking piece screws are tight, waterway, the oil was clear. Check the running of sliding parts on the mold. Such as guide post, guide sleeve, thimble, push rod ejection and other moving parts (bit) should be observed at any time, regular inspection, timely scrub and add lubricating grease, in order to ensure the normal and flexible operation of these sliding parts, to prevent tight biting dead. Adjust die closing, ejection pressure and distance, and install various auxiliary parts (such as water pipe, oil pipe, air extraction device). During the debugging process, check whether there is any damage, leakage or blockage in the connection of water pipe and oil pipe. When the pressure plate bolts of the mold installation are firm and do not become loose, the mold will continue to open and close the die casting machine for three or four times for debugging. ...

1. It will make the alloy structure in the die casting discontinuous; 2. Reduce the air tightness of the workpiece; 3. Die castings are easily corroded; 4. Reduce the strength and plasticity of die castings; 5. Die castings are prone to cracks; 6. The difficulty of later processing increases; 7. The scrap rate of die castings has increased; 8. Harmful impurities cannot pass through environmental protection.

Impurities such as inclusions and foreign particles are common defects in die‑cast parts. They not only spoil surface appearance, but also weaken mechanical properties, air tightness and corrosion resistance of castings, and may even cause large‑scale product rejection. Impurity defects originate from the whole production chain including smelting, metal transfer, pouring and forming. Systematic improvements covering raw‑material control, smelting process, tooling maintenance and environmental management are required. Below are nine key improvement measures with detailed explanations. 1. Control the quality of raw materials Raw materials constitute the primary source of impurities. Ingots shall be delivered with material certificates, and spectral composition tests shall be performed batch‑by‑batch to meet alloy specifications.  Raw materials shall be stored and marked by categories to avoid mixing different grades. Damp, rusty or oil‑stained charges must be dried and cleaned before charging, preventing moisture and contaminants from generating pores and inclusions in molten metal. 2. Use secondary materials according to reasonable proportion Returns such as sprues, overflows and rejected castings tend to form oxide inclusions after remelting, with alloy element loss and impurity accumulation. The proportion of secondary materials must be strictly controlled. Remove oil, coating and dirt from secondary materials before reuse. Regular molten‑metal composition inspection is needed, and the ratio of virgin ingots shall be adjusted accordingly to stabilize alloy components. 3. Adopt high‑quality refining agents for metal smelting Refining is critical for removing hydrogen and oxide slag. Select refining agents matching target alloys, and strictly follow process requirements for refining temperature, duration and dosage. After refining, hold the molten metal long enough for slag to float up, then remove slag completely to stop slag entering the shot sleeve. On‑line degassing equipment is recommended for continuous purification. 4. Apply ceramic filters Install ceramic filters between holding furnace and shot sleeve to intercept oxide and non‑metallic inclusions. Select proper pore size according to casting wall thickness, alloy grade and flow rate. Too coarse filters give poor filtration; too fine ones lead to blockage. Ensure firm installation to avoid unfiltered bypass flow, and replace damaged or blocked filters in time. 5. Vacuum melting and conveying Molten metal is easily oxidized and absorbs hydrogen under atmospheric conditions. Vacuum melting or smelting under protective atmosphere greatly reduces oxidation and gas absorption. Use closed transfer or vacuum‑pouring equipment during metal delivery to avoid secondary oxidation. Vacuum melting and protective‑gas transfer are essential for easily‑oxidized alloys such as magnesium alloys. 6. Adopt ceramic spoons, crucibles and protective tubes; eliminate iron‑made tools High‑temperature molten ...

When summer comes, the maintenance and maintenance of the die-casting machine becomes very critical. As the temperature rises, there will be various small problems of the die-casting machine. So how to maintain the die-casting machine in summer? Longhua die-casting machine is Your detailed explanation: The main reason for the die-casting machine is that its summer is relatively hot, so the oil temperature will be about 20% higher than in the past.In this case, we need to perform necessary replacement and maintenance of the seals during the maintenance process. The reliability of its use can be guaranteed. Die-casting machines have a large demand for cooling water in summer, so the scale in the cooling system of the die-casting machine must be very large, so the waterway needs to be cleaned, and a scale cleaner should be used for cleaning and descaling. Check during the use of the die-casting machine Nitrogen is very sufficient, and ensuring sufficient nitrogen is the key to the use of die casting machine. Before the workers leave work every day, carefully check the oil stains on the die-casting machine, metal, etc., if it is necessary to clean the oil stains on the machine, etc., the most important thing in the maintenance and maintenance of each part of the die-casting machine finishing agent The cleaning of the shooting chamber, etc., clean up the garbage and foreign objects on all parts of the machine, so as to avoid damage to the die casting machine parts when it is turned on again. Check the die-casting machine oil tank, hydraulic pump, hydraulic cylinder, hydraulic motor, hydraulic valve, pipe joints and pressure gauges, and oil circuit board connections for oil leakage before leaving get off work every day. If the die-casting machine has oil leakage, it should be updated immediately. deal with.