General machinery

Die Cast Components for General Machinery

General machinery is unforgiving in a specific way: the parts are not safety-critical enough to justify aerospace pricing, but a housing that leaks or a bracket that will not sit flat stops an assembly line just the same. HKX casts aluminum and zinc components for pump, compressor, gearbox, packaging and material-handling builders, with machining and finishing under the same roof so the tolerance stack stays in one place.

What We Cast for Machinery Builders

Pump and Compressor Housings

Volute and gear pump bodies, compressor crankcases and cylinder heads. These parts carry a sealing function, so porosity is the controlling defect rather than dimensional error. We run them with vacuum-assisted filling where the wall section demands it, then leak test at the pressure the customer specifies — typically 30 Pa pressure decay or a bubble test for lower-volume parts. Bearing bores and shaft bores are machined after casting, not cast to size.

Gearbox and Transmission Casings

Casing halves, covers and end shields for industrial gear units. The challenge here is flatness across a large split face plus bore alignment between two machined features. We hold the split face flat in machining with dedicated fixtures, and control bore position to ±0.05 mm. Rib layout is reviewed at DFM stage — a rib that looks fine on a drawing can create a hot spot that pulls the face out of flat after cooling.

Brackets, Frames and Structural Parts

Mounting brackets, motor feet, machine frames and guard supports. These are usually stiffness-driven rather than tolerance-driven, so the design conversation is about rib placement and draft rather than precision. Straight walls and zero draft are the two most common causes of a quote coming back higher than expected, because both force extra slides or secondary operations.

Control Enclosures and Panels

Distribution boxes, controller housings, amplifier shells and operator panels. Thin walls, tight corner radii and a cosmetic surface on at least one face. Powder coating or anodizing is normally applied here, with masking planned at the finishing stage so threads and grounding points stay conductive.

Tolerances That Matter on Machinery Parts

Most machinery drawings are over-toleranced in the wrong places. As-cast features follow NADCA Standard at roughly ±0.25 mm on the first inch, tightening to ±0.05 mm under NADCA Precision, or ISO 8062-3 CT5–CT7 in metric terms. Machined features reach ±0.05 mm routinely and ±0.02 mm where a bearing or seal demands it. The practical rule we apply at review: tolerance the features that locate the part, leave the rest as-cast. Every tight callout that is not functionally needed adds machining time to every unit for the life of the program. Our tolerance reference lists the achievable values by feature type.

Machine Tonnage and Alloy Selection

Machinery parts spread across our full tonnage range. Small brackets and lamp-adjacent hardware run on 280T; controller enclosures and end caps on 500T; gearbox casings and pump bodies on 800T; large frames and structural housings on 2500T — the full press list sits in our FAQ on the types of machines HKX has. On alloy, A380 (ADC10) is the default for general machinery because it casts well, machines cleanly and costs less than A360. Where corrosion resistance or pressure tightness matters more, A360 or ADC12 is the better call. The material page sets out the trade-offs by property.

Quality Control for Machinery Castings

Incoming chemistry is verified with a spectrometer on every heat. In-process inspection covers shot weight, die temperature and visual checks at the press. Final inspection uses CMM for dimensional layout, X-ray for internal porosity on pressure-tight parts, and hardness testing where the alloy specification calls for it. Sampling frequency follows an agreed control plan; parts that seal a fluid are checked 100% for leak rate. We work to ISO 9001:2015, and IATF 16949 practices are applied where a machinery customer supplies into an automotive line. Where a cast housing is joined to a fabricated frame after machining, the choice between MIG and TIG welding changes both cost and heat input — our MIG vs TIG welding comparison sets out the trade-offs.

Case Data: Three Machinery Parts

Concrete numbers explain the process better than a capability statement. These three jobs are representative of the machinery work we run:

• Gear pump body, A380, 800T plus CNC. 4.2 kg shot weight, 75-second cycle. As-cast surfaces left at CT6; the bore and the mounting face machined to ±0.05 mm. Leak tested by pressure decay at 30 Pa over three seconds, 100% inspection because the part seals oil.
• Industrial gearbox cover, A380, 800T. Large split face where flatness governs assembly. Flatness is held by a dedicated machining fixture rather than by tightening the casting tolerance, which keeps the as-cast die simpler and the unit cost lower.
• Controller enclosure, ADC12, 500T. 1.5 mm wall, cosmetic face on the front, powder coated after masking the grounding points. Cycle time around 65 seconds, packed in bulk for a machinery OEM.

From Drawing to Production

The sequence is DFM review, mold design, tooling, T1 trial, first article inspection, then production. Tooling typically takes four to six weeks depending on cavity count and slide complexity. If you are comparing processes for a machinery part, our service overview covers when die casting is the right answer and when sand casting or fabrication is cheaper. Where a machinery program also supplies into an automotive line, the stricter inspection regime is described under automotive die casting quality. For cost modelling before a drawing exists, the CNC machining cost breakdown explains which features drive the machining portion of the quote. Send a 3D model and drawing to start with a DFM report.

Alloy selection for these housings follows the grades and composition data on our aluminum alloy material page, and the treatments applied after machining are covered under surface finishes.