Operating Instructions and Precautions for Tablet Press Machines

Operating Instructions and Precautions for Tablet Press Machines

I. Single-Punch Tablet Press

A single-punch tablet press can compress various granular materials into round tablets, making it suitable for laboratory trials or small-scale production of medicinal tablets, sugar pills, calcium tablets, and irregularly shaped tablets. It is a compact bench-top electric (or manual) continuous compression machine equipped with one set of dies. The filling depth and tablet thickness can be adjusted, and different mold shapes can be selected based on formulation requirements.

• Understanding the Equipment

1. Main Structure

The single-punch tablet press mainly consists of:

- Dies (one set: upper punch, lower punch, die ring)

- Adjusters (three: pressure, tablet weight, ejection)

- Hopper

- Feeder

- Hand wheel

(Refer to Figures 9-1 and 9-2.)

2. Working Principle

- The lower punch enters the die bore from the bottom, sealing it.

- The feeder fills the die bore with material.

- The upper punch enters from the top and compresses the powder/granules into a tablet.

- The upper punch retracts, while the lower punch rises to eject the tablet.

- A scraper removes the tablet, completing one compression cycle.

- The lower punch then resets for the next filling.

(Refer to Figure 9-3.)

3. Compression Characteristics

- Uses a single set of dies.

- Only the upper punch moves during compression (unilateral pressure), leading to uneven force distribution, which may cause capping or lamination.

- Output: **80–100 tablets/min**, suitable for R&D or small-scale production.

• Operating the Equipment

• Usage Instructions

a. Cleaning & Die Installation

First, clean the machine and select the appropriate dies.

(1) Die Installation

① Lower Punch Installation

- Loosen the lower punch fixing screw.

- Rotate the handwheel to raise the lower punch to its highest position.

- Insert the lower punch (ensure the notch aligns with the screw) and tighten.

② Upper Punch Installation

- Loosen the upper punch clamping nut.

- Insert the upper punch fully and tighten using a wrench (grip the hexagonal base).

③ Die Installation

- Loosen the die fixing screw.

- Place the die horizontally into the die table (ensure the lower punch enters the die bore).

- Tighten the screw. Avoid tilting to prevent damage.

④ Alignment Check

- Rotate the handwheel to lower the upper punch into the die bore.

- If collision/friction occurs, adjust the die table position by loosening its fixing screws (two).

- Repeat until smooth insertion is achieved.

(2) Ejection Adjustment

- Rotate the handwheel to raise the lower punch fully.

- Ensure the punch face is flush with the die table. If not:

- Loosen the butterfly screw and gear plate.

- Adjust the upper gear until aligned, then retighten.

- Manually test-run the machine (~10 rotations) before trial compression.

(3) Filling Depth (Tablet Weight) Adjustment

- Loosen the butterfly screw and gear plate.

- Rotate the lower gear left to raise the lower punch (reduces weight).

- Secure the gear plate and screw after adjustment.

(4) Pressure (Tablet Hardness) Adjustment

- Loosen the connecting rod locknut.

- Rotate the upper punch rod:

- Left = Increased pressure (harder tablets).

- Right = Decreased pressure (softer tablets).

- Tighten the locknut and test-compress ~10 tablets. Check weight, hardness, and surface finish before full production.

(5) Die Removal

① Upper Punch Removal

- Loosen the clamping nut and pull out the punch (use pliers if tight; avoid damaging edges).

② Die Removal

- Loosen the die fixing screw and lower punch screw.

- Adjust the gear to raise the lower punch ~10 mm.

- Gently rotate the handwheel to push the die out partially. Remove by hand.

- If stuck, disassemble the die table.

③ Lower Punch Removal

- Remove the fixing screw and raise the punch fully before extraction (use pliers if needed).

④ Post-Removal Adjustment

- Retract the lower punch ~10 mm to prevent future collisions.

- Reinstall the fixing screw.

2. Maintenance

(1) Lubrication

- Lubricate all moving parts (oil cups, holes, friction surfaces) before use.

- Run idle to distribute oil. Replenish lubricant per shift (avoid overfilling).

(2) Screw Inspection

- Check and tighten screws before each shift and during operation, focusing on:

- Upper punch nut, die screws, lower punch screw.

- Connecting rod locknut, lift fork nuts , butterfly screw, die table screws

(3) Die Cleaning

- Clean dies after each use to ensure tablet appearance quality，And store it in lubricating oil.

II. Rotary Tablet Press

A. Understanding the Equipment

1. Equipment Structure

The main components of a rotary tablet press (Figure 9-4) include:

-Rotating turret (mounted on a central axis)

- Upper and lower punches & dies

- Compression rollers

- Weight adjustment mechanism

- Pressure adjustment mechanism

- Hopper & feeder

- Dust collector

The turret consists of three layers:

- Upper layer: Holds multiple upper punches.

- Middle layer: Contains die bores.

- Lower layer: Houses corresponding lower punches.

During operation:

- Punches rotate with the turret while moving vertically along fixed tracks.

- When passing the compression rollers, the upper punch descends and the lower punch ascends, compressing granules in the die bore.

- A fixed feeder continuously supplies material from the hopper into the dies.

- Pressure adjustment: Achieved by raising/lowering the lower roller, altering the distance between punches.

- Weight adjustment: Controlled via the lower punch track, modifying fill depth before compression.

Common models include 19-station (single-sided) and 35-station (dual-sided) presses.

- Single-sided (e.g., ZP-19): One compression cycle per rotation (1 tablet per die).

- Dual-sided (e.g., ZP-35): Two compression cycles per rotation (2 tablets per die).

2. Working Principle

The compression cycle (Figure 9-5) involves:

1. Filling:

- The lower punch passes under the feeder, filling the die bore.

- The weight adjuster sets the fill height; excess material is scraped off.

2. Compression:

- Punches meet at the rollers, minimizing the gap to form a tablet.

3. Ejection:

- The lower punch rises to eject the tablet, which is guided into a container.

3. Compression Characteristics

- Uniform feeding minimizes weight variation.

- Bilateral pressure ensures even force distribution.

- High output: 80,000–100,000 tablets/hour.

B. Operating the Equipment

1. Die Preparation

- Remove dies from lubricant storage, clean with an oil-free cloth, and disinfect with alcohol.

- Inspect for wear (especially punch tips) before installation.

2. Machine Assembly

(1) Installing Dies

- Loosen die fixing screws on the turret.

- Place the die into the bore and gently tap it flush with the turret surface using a drift pin.

- Tighten screws securely.

(2) Installing Upper Punches

- Remove the upper punch cover, parallel plate, and guide rail.

- Insert each punch, ensuring smooth movement within the die.

- Reinstall guide rails, plates, and covers after all punches are in place.

(3) Installing Lower Punches

- Open the side stainless steel cover and extend the lower punch rail.

- Insert punches sequentially, then lock the rail and cover.

- Rotate the turret manually to confirm smooth operation.

(4) Installing the Feeder

- Secure the crescent-shaped feeder onto the turret with screws.

(5) Installing the Hopper

- Place the hopper into the machine and set the material flow control to mid-position.

3. Machine Calibration

- After assembly, manually rotate the turret to verify alignment.

- Close the safety guard and conduct trial runs.

- Adjust weight (via fill depth) and hardness (via thickness) as needed.

- Monitor tablet quality (weight, hardness, appearance) during production.

4. Shutdown & Cleaning

(1) Material Handling

- Collect leftover material, label it, and submit to the intermediate storage.

(2) Equipment Maintenance

- Clean and lubricate the press.

(3) Workspace Sanitization

- Clean tools, containers, and surfaces.

- QA inspection required before issuing a clearing certificate.

Shanghai Tianfeng Pharmaceutical Equipment Co., Ltd.
No.8 tianfeng road,Songjiang Zone,Shanghai,China
Phone: 86-13524985109
WhatsApp: 86-13524985109
WeChat: 13524985109
Skype: 86-13524985109
Web: www.pilltabletpressmachine.com
E-mail: chenyang@shtf.cn