Screw Conveyor Price in India, Capacity, Pitch and Motor Power Calculation Guide
A screw conveyor price in India depends on the duty, not only the length or diameter. Capacity, pitch, RPM, material bulk density, moisture, abrasiveness, sludge stickiness, inclination, motor power, MOC, liner, sealing and automation all change the final quotation. For sludge handling, especially after dewatering or drying, shaftless screw conveyors are often considered when sticky, fibrous or wet material may choke a normal shafted screw.
At AS Engineers, I usually review screw conveyors as part of the full material handling system around paddle dryers, sludge dryers, bagging systems, silos and pollution-control equipment. A screw conveyor may look simple, but wrong sizing can create choking, high power load, poor discharge, bearing failure and plant downtime.
What is a screw conveyor?
A screw conveyor is a mechanical conveying system that uses a rotating helical screw flight inside a trough or pipe to move bulk material from one point to another. It is commonly used for powders, granules, wet cake, sludge, ash, chemicals, food ingredients, minerals and dried solids.
In a sludge drying or paddle dryer system, a screw conveyor can be used at different points:
| Location in system | Typical use |
|---|---|
| Before dryer | Controlled feeding of wet cake or sludge into the dryer |
| After dryer | Conveying dried sludge or powder from dryer discharge |
| Below cyclone or bag filter | Handling collected fines |
| Before bagging system | Controlled transfer to bagging or silo |
| Below storage hopper | Metered discharge to truck, bag, bin or next process |
AS Engineers’ paddle dryer system documentation includes screw feeder options in the feeding system and screw conveyor options in the product handling system, along with bagging system, silo, bucket elevator and truck disposal arrangements. For plants comparing sludge drying systems, also read our guide on paddle dryers for sludge drying.
Screw conveyor price in India
For industrial buyers, the most practical answer is this: a screw conveyor price in India can start from low-cost catalogue ranges for small/light-duty units, but custom industrial screw conveyors for sludge, chemicals, minerals or dryer discharge are quotation-based.
Public listings in India show small and standard screw conveyor prices in a wide band, from lower-cost flexible units to stainless steel and heavier industrial units. But for plant projects, that range is only a rough reference. A real RFQ must include capacity, material, length, inclination, MOC, motor rating, sealing, safety guarding and site layout.
| Screw conveyor type | Price impact | Buyer note |
|---|---|---|
| Small flexible screw conveyor | Lower | Suitable for light powder or grain-like duties, not always suitable for wet sludge |
| Standard U-trough screw conveyor | Medium | Common for powders, granules, ash, dried sludge and process solids |
| Tubular screw conveyor | Medium to high | Better containment, but cleaning and choking risk must be checked |
| Stainless steel screw conveyor | Higher | Used when corrosion, hygiene or contamination control matters |
| Heavy-duty sludge screw conveyor | Higher | Needs stronger flight, drive, liner, sealing and torque allowance |
| Shaftless screw conveyor for sludge | Usually custom | Better for sticky, wet, fibrous or difficult sludge, but needs liner and torque review |
Do not compare screw conveyor price only by “per feet” rate. A 3-meter MS screw conveyor for dry powder and a 3-meter SS shaftless screw conveyor for wet ETP sludge are completely different machines in duty, drive load and operating risk.
Main factors that change screw conveyor cost
The price changes mainly because each plant handles different material behavior.
| Factor | Why it changes price |
|---|---|
| Capacity required | Higher TPH or m³/hr needs larger diameter, stronger screw, higher drive rating |
| Conveyor length | Longer conveyors need stronger shaft/flight design, supports and drive review |
| Inclination angle | Inclined conveyors lose capacity and need more power |
| Material bulk density | Dense material increases load and motor power |
| Moisture and stickiness | Wet sludge can choke standard shafted screws |
| Abrasion | Ash, minerals and gritty sludge may need wear-resistant flight or liner |
| Corrosion | Chemical sludge may require SS304, SS316 or special MOC |
| Temperature | Hot dryer discharge needs temperature-safe material, seals and bearings |
| Enclosure and sealing | Dusty, odorous or wet material needs better containment |
| Automation | VFD, sensors, interlocks and PLC integration add cost |
| Safety guarding | Drive, coupling, rotating parts and access points need proper guarding |
For sludge dryer projects, screw conveyor selection should be matched with dewatering, drying and product handling. If the upstream system is still under selection, this guide on how paddle dryers work for sludge drying will help connect dryer output condition with material handling design.
Screw conveyor capacity calculation
The basic screw conveyor capacity calculation starts with the volume of material moved per revolution.
Basic volumetric capacity formula
For a shafted screw conveyor:
Q = 60 × A × P × N × F × C
Where:
| Symbol | Meaning | Unit |
|---|---|---|
| Q | Volumetric capacity | m³/hr |
| A | Available cross-sectional area inside screw | m² |
| P | Screw pitch | m/revolution |
| N | Screw speed | RPM |
| F | Filling factor | decimal |
| C | Inclination correction factor | decimal |
For a shafted screw:
A = π/4 × (D² − d²)
Where:
| Symbol | Meaning |
|---|---|
| D | Outer screw diameter in meters |
| d | Shaft diameter in meters |
For a shaftless screw conveyor, there is no central shaft, so the available area is higher in principle. But sludge behavior, liner friction and torque become more important than just area.
Mass capacity formula
Once volumetric capacity is calculated:
Capacity in kg/hr = Q × bulk density
Capacity in TPH = Q × bulk density ÷ 1000
Example:
| Input | Value |
|---|---|
| Screw diameter | 300 mm |
| Shaft diameter | 90 mm |
| Pitch | 300 mm |
| Speed | 35 RPM |
| Filling factor | 30% |
| Inclination factor | 1.0 |
| Bulk density | 700 kg/m³ |
Calculation:
A = π/4 × (0.30² − 0.09²)
A = 0.0643 m²
Q = 60 × 0.0643 × 0.30 × 35 × 0.30 × 1.0
Q = 12.15 m³/hr
Mass capacity = 12.15 × 700 = 8,505 kg/hr
Approximate capacity = 8.5 TPH
This is a preliminary calculation only. Final design must also check screw speed limit, trough loading, lump size, starting torque, inclination, bearing arrangement, material flowability and site discharge condition.
Screw conveyor pitch calculation
Screw pitch is the distance between two flight edges in one full revolution. Pitch controls how much material is moved per revolution.
Common pitch rules
| Pitch type | Approximate pitch | Use case |
|---|---|---|
| Standard pitch | P = D | Common for horizontal conveying of free-flowing material |
| Short pitch | P = 0.5D to 0.67D | Inclined conveying, controlled feeding, sticky or sluggish material |
| Half pitch | P = 0.5D | Feeder duty, controlled discharge from hopper |
| Variable pitch | Increasing pitch along length | Helps draw material evenly from longer inlet zones |
| Long pitch | P = 1.5D or more | Free-flowing light material, not preferred for difficult sludge |
For sludge, short pitch or shaftless design may be safer than standard pitch when the material is sticky, wet, fibrous or difficult to discharge. If the screw conveyor is feeding a dryer, pitch should be selected for controlled feed rate. If it is after dryer discharge, pitch should be selected for actual dried product behavior.
Screw conveyor motor power calculation
Motor power depends on more than capacity. A conveyor may handle the required TPH but still fail if torque, startup load and friction are underestimated.
Practical motor power logic
Use this structure for preliminary power estimation:
Motor kW = (Empty running power + material conveying power + lift power) ÷ drive efficiency × service factor
| Component | What it covers |
|---|---|
| Empty running power | Screw, shaft, bearings, seals and trough friction without material |
| Material conveying power | Power needed to move material along the conveyor length |
| Lift power | Extra power needed if conveyor is inclined or vertical |
| Drive efficiency | Gearbox, belt/chain and coupling losses |
| Service factor | Allowance for starting load, sludge variation, duty cycle and shock load |
Simple preliminary material power formula
For horizontal conveying, a rough preliminary relation is:
P = Q × L × K ÷ (3600 × 102)
Where:
| Symbol | Meaning |
|---|---|
| P | Power in kW |
| Q | Capacity in kg/hr |
| L | Conveyor length in meters |
| K | Material/friction coefficient |
This is not enough for final motor selection, but it helps buyers understand why a longer conveyor, heavier material or sticky sludge increases motor rating.
Example motor power estimate
| Input | Value |
|---|---|
| Capacity | 5,000 kg/hr |
| Conveyor length | 8 m |
| Friction coefficient | 4 |
| Drive efficiency | 85% |
| Service factor | 1.5 |
| Empty power allowance | 0.5 kW |
Material power:
P = 5000 × 8 × 4 ÷ (3600 × 102)
P = 0.44 kW
Add empty power:
0.44 + 0.5 = 0.94 kW
Adjust for efficiency and service factor:
0.94 ÷ 0.85 × 1.5 = 1.66 kW
In this case, the selected motor may be rounded up to the next practical rating after checking torque, RPM, gearbox ratio and starting condition. For sticky sludge, the motor may need a higher service factor than a dry powder application.
Shafted vs shaftless screw conveyor
The right choice depends on the material.
| Point | Shafted screw conveyor | Shaftless screw conveyor |
|---|---|---|
| Center shaft | Yes | No |
| Best for | Powders, granules, dry solids, many free-flowing materials | Wet sludge, sticky cake, screenings, fibrous material |
| Choking risk | Higher with sticky material around shaft | Lower because there is no central shaft obstruction |
| Wear interface | Flight and trough | Spiral and liner |
| Torque demand | Usually moderate | Can be higher for sludge |
| Maintenance focus | Shaft, hanger bearing, flight wear, end bearings | Spiral wear, liner wear, drive torque, discharge condition |
| Sludge suitability | Depends on sludge condition | Often better for difficult sludge |
Shaftless screw conveyor for sludge
A shaftless screw conveyor for sludge is useful when the material is wet, sticky, viscous, fibrous or difficult to move in a normal shafted screw. Because there is no central pipe shaft, the sludge has more open space inside the conveyor, and the risk of wrapping or bridging around the shaft is reduced.
It is commonly considered for:
- Dewatered ETP sludge
- STP sludge
- Municipal sludge
- Biological sludge
- Paper sludge
- Sticky industrial sludge
- Screenings and fibrous waste
- Wet cake before drying
- Dried sludge where lumps and irregular texture remain
For a sludge drying line, the conveyor should be selected based on feed moisture, final dryness, expected lumps, discharge temperature, stickiness, odor control requirement and downstream handling method. In many cases, the screw conveyor is not an isolated item. It must match the dryer discharge, bagging system, silo or truck loading arrangement.
For downstream sludge handling context, you can also read our guide on industrial sludge disposal and the role of drying in reducing handling challenges.
Common mistakes in screw conveyor selection
Selecting by motor HP only
A 3 HP screw conveyor from one supplier may not be equal to another 3 HP conveyor. Diameter, RPM, gearbox ratio, pitch, trough loading and material behavior decide performance.
Ignoring bulk density
A conveyor designed for 500 kg/m³ material may overload when used for 1,200 kg/m³ material.
Using standard pitch for sticky sludge
Standard pitch may work for dry powder but may not discharge sticky sludge smoothly. Sludge may require short pitch, shaftless design, better liner or controlled feed.
Forgetting inclination loss
Capacity reduces when the conveyor is inclined. Power demand also increases.
Not checking discharge condition
Many screw conveyor problems happen at the discharge end. If the outlet is too small, blocked, poorly aligned or connected to a closed system without venting, material backup can overload the screw.
Weak access and cleaning design
Wet sludge and chemical solids need cleaning access, inspection covers and safe maintenance space.
Poor safety guarding
Screw conveyors have rotating flights and moving drive parts. Guards, covers, lockout practice and emergency stops must be planned. Conveyor safety references such as OSHA conveyor requirements and WorkSafe screw conveyor guidance also emphasize guarding and preventing contact with rotating parts.
RFQ checklist for screw conveyor quotation
Before asking for screw conveyor price in India, share proper duty data. This avoids under-quotation, wrong sizing and revision delays.
| RFQ input | What to share |
|---|---|
| Material name | Sludge, powder, ash, chemical, dried solids, wet cake |
| Bulk density | kg/m³ |
| Moisture | Initial and operating moisture |
| Capacity | kg/hr, TPH or m³/hr |
| Conveyor length | Inlet to outlet distance |
| Inclination | Horizontal or angle in degrees |
| Required height | Feed and discharge elevations |
| Material temperature | Ambient, hot dryer discharge or cooled |
| MOC requirement | MS, SS304, SS316 or special alloy |
| Abrasion/corrosion | Yes/no and expected severity |
| Flow behavior | Free-flowing, sticky, fibrous, lumpy, bridging |
| Conveyor type | U-trough, tubular, shaftless, feeder screw |
| Drive preference | Fixed speed or VFD |
| Sealing requirement | Dust, odor, vapor or leakage control |
| Safety requirement | Guards, covers, E-stop, interlocks |
| Integration | Dryer, hopper, silo, bagging system, truck loading |
| Site constraints | Space, access, cleaning, maintenance clearance |
Where screw conveyors fit in paddle dryer and sludge dryer systems
In a paddle dryer system, AS Engineers documentation shows screw feeder as one feeding option and screw conveyor as one product handling option. The full system may include fuel resources, heating system, feeding system, paddle dryer, scavenging system, pollution control system, solvent management and product handling system.
This matters because screw conveyor design changes depending on location.
| System area | Conveyor selection logic |
|---|---|
| Wet feed to dryer | Needs controlled feed, anti-bridging and torque allowance |
| Dryer discharge | Must handle hot, dried, semi-dried or lumpy material |
| Cyclone discharge | Must handle collected fines and airlock discharge |
| Bag filter discharge | Must handle fine dust and avoid leakage |
| Bagging feed | Must provide steady discharge rate |
| Silo/truck loading | Must match height, angle and site layout |
If the screw conveyor is part of a drying system, also check connected equipment such as cyclone separator design, bag filter types and scrubber working principle because fines, vapor and dust handling can affect the complete layout.
Conclusion
Screw conveyor price in India should not be judged only by diameter, length or motor HP. The correct quotation depends on capacity, bulk density, pitch, RPM, inclination, sludge behavior, MOC, sealing, drive torque, liner, safety guarding and integration with upstream and downstream equipment.
For sludge and dryer-related applications, shaftless screw conveyors may be suitable when the material is sticky, wet, fibrous or difficult to move with a standard shafted screw. For dry powders and granules, a properly sized shafted screw conveyor may be more practical and cost-effective.
If you are planning a screw conveyor for sludge handling, paddle dryer feeding, dryer discharge, bagging, silo loading or product handling, share the material details, required capacity, moisture, bulk density, length, inclination and site layout. The AS Engineers team can review the duty condition and suggest a suitable conveying arrangement based on real plant requirements.
FAQs
What is the price of a screw conveyor in India?
Screw conveyor price in India varies widely because it depends on diameter, length, MOC, capacity, motor power, inclination, sealing, safety guarding and material behavior. Small standard units may appear at lower catalogue prices, while industrial sludge or stainless steel screw conveyors are usually custom-quoted.
How do you calculate screw conveyor capacity?
Screw conveyor capacity can be estimated using Q = 60 × A × P × N × F × C, where A is available screw area, P is pitch, N is RPM, F is filling factor and C is inclination correction factor. Mass capacity is then calculated by multiplying volumetric capacity by bulk density.
What is standard screw conveyor pitch?
Standard screw conveyor pitch is generally equal to the screw diameter. Short pitch, such as 0.5D to 0.67D, is often used for inclined conveying, controlled feeding or sluggish materials. Sticky sludge may need short pitch or shaftless screw design.
How do you calculate screw conveyor motor power?
Motor power is estimated from empty running power, material conveying power, lift power, drive efficiency and service factor. Final motor selection must also check starting torque, gearbox ratio, screw speed, sludge stickiness and duty cycle.
Is shaftless screw conveyor good for sludge?
Yes, a shaftless screw conveyor is often suitable for wet, sticky, fibrous or dewatered sludge because there is no central shaft obstruction. However, liner wear, torque load, discharge condition and cleaning access must be reviewed before final selection.
