Frequently Asked Questions

It depends on traffic level. Light commercial (offices, retail): 0.5-1mm (20-40 mil) self-leveling epoxy is sufficient. Medium industrial (warehouses, workshops): 1-3mm (40-120 mil) epoxy mortar or self-leveling system. Heavy industrial (factories, logistics centers): 3-5mm (120-200 mil) epoxy quartz sand mortar system. For areas with heavy forklift traffic or chemical exposure, we recommend the 3mm+ epoxy mortar system with a polyurethane topcoat for extra abrasion resistance.

Yes, but proper surface preparation is critical. The concrete must be structurally sound — cracks wider than 0.3mm need epoxy injection repair first. We diamond-grind the entire surface to CSP 3-5 profile, remove all laitance, oil, grease, and contaminants, then apply a penetrating epoxy primer. Loose or delaminated concrete must be cut out and patched with epoxy mortar. If the old concrete has moisture issues (MVT > 5 lbs), a moisture barrier primer is required to prevent future delamination.

The most common causes are: (1) Poor surface prep — insufficient grinding or contaminated concrete prevents proper adhesion. (2) Moisture vapor transmission (MVT) — concrete slab moisture >5 lbs/1000 sq ft/24h pushes epoxy off from below. (3) Outgassing — porous concrete releases trapped air during epoxy cure, especially in hot weather. (4) Incorrect mixing ratio or rushed installation. (5) Applying epoxy over sealed or painted surfaces without proper mechanical abrasion. Our installation guide covers all these prevention steps — proper diamond grinding, moisture testing, and priming eliminate 95% of failures.

Start by matching the bond type to your concrete hardness. For soft concrete (≤C25): use hard bond metal pads to slow down diamond wear and maximize life. For medium concrete (C25-C35): medium bond works best for balanced cutting and durability. For hard concrete (≥C35): soft bond metal pads ensure diamonds expose new cutting edges as they wear. Then select the grit sequence: start with 30/40 grit metal bond for aggressive stock removal and coating removal, progress through 100/200 grit metal bond for refinement, then transition to 400/800/1500/3000 grit resin bond for polishing to your desired sheen level.

A standard polished concrete sequence has 4 stages. Stage 1 — Cut & Prep: 30/40 grit metal bond (opens up concrete, removes imperfections). Stage 2 — Refine: 100 grit then 200 grit metal bond (refines scratch pattern, hybrid transition). Stage 3 — Polish: 400 grit then 800 grit resin bond (builds clarity and sheen). Stage 4 — Finish: 1500 grit then 3000 grit resin bond (achieves high-gloss mirror finish, 80+ gloss meter reading). For epoxy coating removal, add a 16 grit PCD segment step before the 30 grit stage. Each step must remove 100% of the previous grit's scratches — skip grits and you'll see the pattern in the final finish.

Metal bond pads use a metallic matrix (cobalt/nickel/bronze alloy) that holds diamonds firmly. They cut aggressively, last long (2-5x longer than resin), and are used for the initial grinding and refining stages (16-200 grit). Resin bond pads use a phenolic resin matrix that wears faster, exposing new diamonds continuously. They produce progressively finer finishes and are used for polishing stages (400-3000 grit). Metal bond = fast stock removal, flat floor, long life. Resin bond = fine finish, clarity, gloss. You can't skip from metal bond directly to high-grit resin — the 200 grit metal to 400 grit resin transition is the critical hybrid step.

Tool life varies dramatically by application. Metal bond grinding shoes: 5,000-15,000 sq ft per set on medium concrete — longer on hard concrete (slower wear), shorter on soft abrasive concrete (faster wear). Resin polishing pads: 2,000-8,000 sq ft per set per grit. PCD (polycrystalline diamond) coating removal tools: 10,000-30,000 sq ft per set for thin coatings like epoxy. Factors that reduce life: heavy pressure, high RPM, skipping grits, grinding over expansion joint filler, and using the wrong bond hardness for the concrete. Our diamond tool life guide has exact formulas and maintenance tips to maximize your ROI.

It depends on the job site and finish goal. Wet grinding: produces the best finish quality (no heat-induced micro-scratches), longer tool life (water cools and lubricates), zero dust. But it creates slurry that requires containment and disposal, and needs time to dry before subsequent coats. Dry grinding: faster setup, no slurry disposal, works in moisture-sensitive areas. But it generates massive dust (require industrial HEPA vacuums), tools wear 30-50% faster from heat, and fine scratch patterns are harder to eliminate. Best practice: dry grind for coating removal and coarse grinding (with HEPA vac), then switch to wet for final polishing stages if a high-gloss finish is required.

Diamond tools themselves are safe when used correctly, but the grinding process has three main hazards. First, silica dust — concrete contains crystalline silica that causes silicosis; always use a HEPA dust collector rated for silica, wear an N95+ respirator, and use wet methods where possible. Second, kickback and flying debris — always stand to the side of the grinder, never directly behind, and wear safety glasses and face shield. Third, electrical safety — wet grinding near electricity is dangerous; use GFCI-protected circuits and never operate wet grinders with damaged cords. Our safety guide covers full PPE requirements, dust handling protocols, and OSHA silica compliance.

Standard smooth epoxy is somewhat slippery when wet, but there are multiple solutions. For light slip resistance: broadcast fine silica sand or aluminum oxide into the topcoat (10-20 grit = aggressive, 60-80 grit = subtle). For medium slip resistance: broadcast quartz aggregate or use textured epoxy topcoat systems (matches ADA/OSHA requirements for commercial kitchens and industrial floors). For heavy slip resistance: anti-slip epoxy coating with 20-40 grit aluminum oxide broadcast, or epoxy mortar systems with exposed aggregate texture. All our epoxy systems can be customized with slip-resistant additives — we recommend getting samples tested at your facility to match your exact needs.

Standard commercial epoxy flooring handles continuous service temperatures up to 140-176°F (60-80°C). Short-term exposure (hot pans, tools, etc.) up to 212°F (100°C) is usually fine without damage. For higher temperatures: heat-resistant epoxy systems can handle continuous 212-300°F (100-150°C). For extreme heat like foundries or bakeries: polyurethane mortar systems handle up to 248°F continuous and 392°F (200°C) intermittent. Never pour boiling water directly on epoxy or place hot welding equipment without a heat shield — thermal shock can cause discoloration or blistering.

Epoxy floors are low-maintenance but not zero-maintenance. Daily: dry dust mop or auto-scrub with a neutral pH cleaner (pH 7-9) to remove abrasive dirt that scratches the surface. Weekly: deep clean with an auto-scrubber using a red or white pad — never use black stripping pads on epoxy. Monthly: inspect for any chips, scratches, or worn areas, especially at high-traffic entry points. Annually: apply a fresh coat of clear polyurethane or epoxy topcoat in high-traffic areas to restore gloss and extend life. Never use: harsh acids, bleach, citrus cleaners, or abrasive scouring powders — these can dull or etch the epoxy surface. Our maintenance guide has the complete cleaning schedule and product recommendations.

Key factors to evaluate. Motor power: 5HP minimum for single-head, 10HP+ for triple-head planetary grinders doing commercial work. Grinding width: 10-17 inch for single-head (edging, small jobs), 20-32 inch for triple-head planetary (production grinding). Weight: heavier = better stock removal, 150-300 lbs for commercial use. Dust collection: must have built-in vacuum port or companion HEPA dust collector (OSHA silica requirement). Gearbox: planetary gear drive for consistent results and long life. Also consider: voltage compatibility (110V vs 220V vs 380V 3-phase), tool plate compatibility (quick-change vs bolt-on), and spare parts availability. Our buying guide has a full comparison matrix of all major brands.

For diamond tools and consumables: our standard MOQ is 10 pieces per item, but we offer mixed-item wholesale — you can combine different grits and types to reach a $500 minimum order value. For first-time customers: we offer a sample pack at a discounted rate so you can test our tools before committing to larger orders. For epoxy materials: 200kg minimum for bulk drum orders, with sample kits available. For custom branding (OEM/ODM): 500 pieces minimum for laser-engraved logos, 1000 pieces minimum for custom packaging. Contact our sales team at sales@yumeigu.com for exact pricing based on your volume.

For standard stocked items (diamond tools, grinding pads, common epoxy products): 3-5 business days production + 5-10 days international shipping by sea, or 3-5 days by air express (DHL/FedEx/UPS). Total: 8-15 days by sea, 6-10 days by air. For custom orders (OEM branding, special sizes, custom epoxy formulations): 10-15 business days production + shipping time. For large container orders (20ft/40ft): 15-25 days production + 15-30 days sea freight depending on destination. We always provide tracking numbers as soon as your order ships, and our sales team keeps you updated on production progress.

Yes, all our products meet international standards. Epoxy flooring systems: CE certified (EU), ISO 9001 quality management, ISO 14001 environmental, low VOC certified (<50 g/L), fire resistance rated per ASTM E84 Class A. Diamond tools: CE marked, MPA safety certified, ISO 9001 production. Floor grinders: CE certified, GS safety mark, EMC compliant. We can provide test reports, material safety data sheets (MSDS/SDS), and third-party lab certificates upon request. For specific project certifications (LEED, FDA, food-grade), contact our technical team — we have formulations that meet NSF/ANSI 61 and FDA 21 CFR 175.300 standards for food contact areas.

Epoxy is the most common industrial flooring — excellent chemical resistance, seamless, glossy, very cost-effective at $2-5/sq ft installed. Best for warehouses, workshops, showrooms, and general commercial use. Polyurethane mortar is a heavier-duty system — extreme thermal shock resistance (handles -40°F to 250°F), better UV stability (doesn't yellow), slightly more flexible, but 2-3x more expensive ($6-12/sq ft). Best for food processing plants, bakeries, pharmaceutical facilities, and areas with frequent hot water washdowns. Quick rule: if you need hot water cleaning or extreme temperature swings → polyurethane mortar. For everything else → epoxy usually gives better value.

Yes, but you need food-grade certified epoxy systems. Our food-safe epoxy coatings meet NSF/ANSI 61 and FDA 21 CFR 175.300 standards for indirect food contact. Key requirements for food facilities: seamless, non-porous surface (no bacteria harborage), resistant to caustic cleaners and hot water washdowns, coved base (integral curved wall-floor transition for easy cleaning), and slip-resistant texture for wet processing areas. For wet food processing with frequent hot water (bakeries, meat processing), we recommend polyurethane mortar systems instead of standard epoxy — they handle thermal cycling much better.

Terrazzo restoration costs depend on condition and finish level. Basic grind & seal (clean + grind + polish to 800 grit + topical sealer): $3-5 per sq ft. Full diamond polish (grind through full grit sequence to 3000 grit + densifier + guard): $5-10 per sq ft. Restoration with repairs (crack filling, chip repair, joint patching, stain removal): $8-15 per sq ft. Full restoration + new grout + sealer + gloss finish: $10-20 per sq ft. Factors that increase cost: heavy damage (cracks, chips, stains), multiple layers of old coating to remove, large aggregate exposure requirements, and decorative elements like custom borders or logos. We offer free site assessments — send photos and we'll give you an accurate quote.