31001001 Original Schmidt Mechanical Concrete Rebound Hammer

Marke: Screening Eagle (Formerly Proceq, Schweiz)

Bestell-Nr.: 310 01 001 (31001001)

Vollständiger Modellname: Original Schmidt Type N (Metric MPa Scale Version)

Distinction of similar part numbers:

31001002 = Type N (PSI Imperial Scale); 31002000 = Type NR with recording paper

1. Grundlegende technische Spezifikationen

Impact Energy: 2.207 N·m (2.207 J), standard impact energy for Type N international specification

Applicable Concrete Compressive Strength: 10 ~ 70 MPa (1450 ~ 10152 psi)

Minimum thickness of test member: ≥100 mm, structure must be rigidly supported

Maximum aggregate size: ≤32 mm

Reading method: Mechanical vernier scale, manual reading of rebound number R

Gewicht: Ca. 1090 G

Konforme Standards: JGJ/T 23, IN 12504-2, ASTM C805, ISO 1920-7

2. Standard Delivery Scope
3. Original Schmidt Type N Rebound Hammer Main Unit
4. Standard Reference Steel Anvil
5. Heavy-duty Protective Carry Case
6. Bedienungsanleitung, Factory Calibration Certificate
7. Strength Conversion Graph (Printed on instrument housing)
8. Anwendungsbereich

✅ In-situ non-destructive strength survey for cast-in-place concrete beams, columns, floor slabs and precast components

✅ On-site screening of concrete homogeneity, reference for formwork stripping strength

✅ Large-area rapid testing combined with core drilling method

❌ Not suitable: Thin members with thickness＜100 mm, fresh low-strength concrete (Prioritize Type L, Order No.31003002)

4. Original Schmidt Series Model Comparison

5. Ergänzende Hinweise
6. This is the classic original mechanical Schmidt rebound hammer, the benchmark prototype referenced by global rebound test standards;
7. Pure mechanical design, batterielos, suitable for long-term field operation;
8. Periodic verification on matched reference steel anvil is mandatory;
9. Often compared with domestic HT225 rebound hammer in Chinese market, but impact mechanism and calibration system are non-interchangeable; strength conversion curves cannot be directly applied.

Complete Technical Document for Proceq Original Schmidt N (31001001)

1. Standard Field Operation Guidelines

1.1 Pre-test Preparation

1. Umgebungstemperaturbereich: -4℃ ~ +40℃, avoid direct sunlight exposure and extreme cold airflow;
2. Sichtprüfung: Ensure plunger free of bending, impact damage and rust; smooth extension and retraction; indicator slider moves without jamming;
3. Perform anvil verification before and after testing work every day;
4. Test surface preparation: Remove laitance and loose concrete layer; grind flat with abrasive stone and keep dry.

1.2 Impact Operation Specification

1. The rebound hammer must be perpendicular to the concrete test surface; record impact angle for subsequent angle correction when testing horizontally, upward or downward;
2. Apply force slowly and steadily until internal mechanism trips automatically; do not strike the housing abruptly;
3. Maintain contact pressure after impact before reading, avoid releasing the plunger prematurely;
4. 16 test points per test area; discard 3 maximum and 3 minimum readings, calculate average value of remaining 10 Punkte;
5. Minimum spacing between test points ≥30 mm; minimum distance from component edge ≥50 mm;
6. Repeated impact on the same test point is prohibited.

1.3 Daily Maintenance Prohibitions

❌ Disassembly of internal movement assembly without authorization;

❌ Do not apply lubricating oil to plunger and guide sleeve (dust adhesion causes indicator jamming);

✅ Only wipe plunger with lint-free dry cloth;

✅ Store inside original hard case during long-distance transportation to prevent heavy drop impact.

1.4 Common Operation Mistakes

Inclined impact → Systematically low rebound readings

Release immediately after impact → Distorted readings

Cement mortar adhered on plunger → High data dispersion

Thin member (＜100 mm) tested without rigid backing → Underestimated strength results

2. Steel Anvil Verification (Kalibrierung) Specification for Original Schmidt Type N

Factory-supplied reference anvil: Hardness HRC 62±2, mass 16 kg. Not interchangeable with steel anvils for domestic HT225

2.1 Verification Conditions

1. Place the steel anvil on a stable rigid base; wooden boards or rubber mats are not allowed;
2. Top surface of anvil shall be clean, rust-free and free of indentations;
3. Operate rebound hammer vertically downward onto the anvil;
4. Pre-impact 3～5 times before formal readings to stabilize mechanical movement.

2.2 Verification Procedures

1. Conduct continuous 8 impacts;
2. Rotate plunger by 90° after each impact to verify uniform contact surface;
3. Eliminate maximum and minimum readings, compute average value of remaining 6 results.

2.3 Acceptance Criteria

✅ Factory standard verified rebound number: 80 ± 2

If average value ＜78 or ＞82: Instrument out of tolerance; maintenance or factory service required.

⚠️ Critical Notice: Proceq Schmidt steel anvil ≠ HT225 domestic steel anvil!

Verification data obtained using domestic anvil for Schmidt hammer has no metrological validity!

2.4 Verification Frequency

1. Perform verification before start and after completion of daily testing;
2. Mandatory re-verification after instrument drop or long-distance transportation;
3. Annual metrological certification together with the instrument.
4. Leistungsvergleich: Original Schmidt N (31001001) VS Domestic HT225

Both feature nominal impact energy of 2.207 J, but movement structure, conversion curves and spare parts are fully non-interchangeable

Critical Practical Reminder

Do NOT calculate concrete strength of Schmidt rebound readings directly using HT225 conversion tables!

For project acceptance within China, establish specific strength conversion curves or adopt core drilling correction in accordance with JGJ/T23.

4. List of Common Wear Parts for Original Schmidt N (Official Proceq Part No.)

Applicable to 31001001 (Mechanical Type N without recording mechanism)

1. 31099038 Plunger — Highest-frequency wearing part; replace if end face suffers impact dent, abrasion or deformation
2. Impact Spring Assembly — Elastic degradation after hundreds of thousands of impacts (Mostly supplied as assembly for factory replacement; loose spring seldom sold separately)
3. Indicator Rider Assembly — Abrasion and abnormal friction lead to unstable readings
4. Front felt seal & O-ring set — Dust-proof components; aging and dust ingress cause indicator jamming
5. Buffer Spring — Fatigue fracture results in impact noise and abnormal tripping action
6. Catch Hook Assembly — Wear leads to failure of normal tripping and loading
7. Reference Steel Anvil: Order No.31089001
8. Wartung & Calibration Service Certificate No.31089000

Ergänzende Anmerkung: Few qualified aftermarket alternative spare parts available domestically. Severe internal component damage generally requires service via Proceq authorized service centers; on-site component replacement like HT225 is not feasible.

Official Wear Parts List for Proceq Original Schmidt N (Bestell-Nr.:31001001)

Applicable to mechanical Type N without recording paper; No spare parts are interchangeable with domestic HT225; mature aftermarket alternatives for core components are unavailable in China

1. High-frequency Field Serviceable Spare Parts (Available for Separate Order)

2. Movement Spring Components (Mainly Supplied as Assembly; Loose Parts Rarely Sold Separately)
3. Impact Spring Assembly

Elastic fatigue and reduced spring force → Average anvil verification reading lower than 78, systematic low measurement results. Proceq generally does not supply loose springs; complete movement assembly replacement is common.

2. Buffer Spring

Breakage or slack → Impact abnormal noise, irregular tripping.

3. Catch Hook / Pawl Assembly

Long-term friction wear → Failure to lock, premature tripping, unable to complete loading stroke.

4. Hammer Mass

Rarely damaged; replacement only required after severe drop-induced deformation.

3. Gehäuse & Auxiliary Accessories
4. Carrying Case: Broken latches or housing damage
5. Conversion chart sticker: Faded strength curve marking
6. Rear cap / Front screw cap: Thread stripping and impact deformation
7. Important Procurement & Wartungsrichtlinien
8. Model Distinction: Spare parts for 31001001 (Typ N) are incompatible with 31003002 (Low-energy Type L); mixing parts is forbidden.
9. Maintenance Policy: Authorized domestic service providers mostly offer complete instrument overhaul and calibration service for internal precision parts such as springs and hooks; loose components are generally not sold individually.
10. Compatibility Restrictions:

✘ Replacement with HT225 plunger, springs or steel anvil is prohibited;

✘ Anvil verification using domestic steel anvil has no metrological validity for Schmidt hammer.

4. Recommended Precautionary Spare Parts Inventory:

Kolben (31099038), front felt seal kit, indicator slider assembly.

5. Disposable Consumables for Field Testing

Silicon carbide abrasive grinding stone

Lint-free dry wiping cloth (Lubricant application on plunger is prohibited)

Annual factory calibration certification service (Order No.31089000)