Shumai Machine: Common Faults, Troubleshooting, and Practical Solutions

I. Issue 1: Loose seals, leaking glutinous rice, and inconsistent size/weight
Problem Description
The tops of the finished *shaomai* fail to seal tightly, causing glutinous rice to leak out during steaming; there are significant discrepancies in size and filling quantity within the same batch, resulting in a low product pass rate.
Primary Causes: Loose forming molds; mismatch between dough wrapper feeding speed and filling injection speed; glutinous rice filling is too runny; mold wear has created excessive gaps.
Actionable Solutions
1. Power down the machine, tighten the mold mounting screws, and realign the mold halves;
2. Fine-tune the frequency converter parameters to synchronize the wrapper feeding speed with the filling flow rate;
3. Drain excess moisture from the glutinous rice filling to prevent spillage caused by a runny or soft consistency;
4. Replace worn-out molds with genuine OEM parts;
5. If parameter adjustments prove ineffective, contact us for free remote technical guidance; for severe malfunctions, schedule an on-site inspection.
Summary of Key Steps:
Tighten molds → Synchronize wrapper and filling speeds → Drain excess filling moisture → Replace worn molds.

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II. Issue 2: Filling feed screw jams; sticky rice feed stutters or fails to dispense filling
Problem Description:
Sticky rice filling gets stuck between the hopper and the feed screw; filling delivery is intermittent, requiring frequent shutdowns for cleaning and preventing continuous production.
Primary Causes: Sticky rice clumping due to excess moisture; meat chunks in the filling being too large/hard; accumulation of dried sticky rice residue in the screw clearance; feed screw rotation speed being too low.
Actionable Solutions:
1. Drain excess moisture from the sticky rice beforehand, reduce the size of diced filling ingredients, and remove large, hard food particles;
2. Completely disassemble and wash the feed screw after each day's production to remove dried, hardened sticky rice;
3. Moderately increase the feed screw rotation speed to reduce the likelihood of jamming;
4. If jamming persists despite adjustments, request a remote video inspection of the equipment structure.
Summary of Key Steps:
Optimize filling consistency → Thoroughly clean the feed screw daily → Properly adjust the feed screw rotation speed.

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III. Issue 3: Dough sheet tearing/damage and misalignment during transport
Problem Description:
The dough sheet tears or shifts laterally during transport, preventing precise feeding into the forming station; this results in an increased number of defective products (e.g., empty wrappers or unfilled units).
Primary Causes: Dough sheet is too dry or stiff; glutinous rice residue is causing jams on the transport track; belt tension is uneven across its width; guide baffles are misaligned.
Actionable Solutions:
1. Seal the dough sheet to retain moisture and prevent drying/hardening; lightly mist with water to soften if necessary;
2. Clean glutinous rice residue from the transport platform and belt surface;
3. Adjust the tensioning bolts on both sides of the belt to ensure uniform tension;
4. Align the guide baffles on both sides to restrict lateral shifting of the dough sheet;
Summary of Key Steps:
Moisturize and clean dough sheet → Adjust belt tension → Align guide baffles.

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IV. Issue 4: Excessive vibration and noticeable abnormal noise during operation
Problem Description:
The machine body shakes violently during operation; friction-related noises occur during the rotation of the auger and mold; and prolonged vibration causes screws to frequently come loose.
Primary Causes: Machine body not leveled; leveling feet not making contact with the ground; lack of lubrication in the auger bearings; loose mounting screws on the machine.
Actionable Solutions:
1. Adjust the anti-slip leveling feet and position the machine on a flat surface to ensure it is level;
2. Thoroughly tighten all mounting screws for the hopper, mold, and motor;
3. Apply food-grade lubricant to the auger and drive bearings;
4. Replace worn bearings promptly with genuine OEM parts.
Summary of Key Steps:
Level the machine body → Tighten all screws → Lubricate drive bearings.

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V. Issue 5: Difficulty distinguishing between tabletop and assembly-line models; production capacity mismatch
Issue Description:
Unsure whether a small shop requires a tabletop model or a large-scale assembly-line system; concerns regarding selecting the wrong machine for glutinous rice fillings, or issues with voltage compatibility and installation space.
Actionable Steps:
1. Gather data on daily“shumai”production volume, available floor space dimensions, and power supply (220V/380V), then contact customer service for a free, personalized model recommendation;
2. For breakfast stalls and small shops with a daily output of under 10,000 units, choose a 220V tabletop“shumai”machine; these are compact and easy to move;
3. For high-volume production in central kitchens or frozen food processing plants, choose a 380V floor-standing assembly-line model; these can be integrated with cooling and packaging equipment;
4. If a complete dim sum production line is required, free workshop layout planning services are available.
Summary of Key Steps:
Precisely match the machine model to production volume, space constraints, and power supply to avoid wasteful purchasing.