KT-956-D vs KT-986 Duct Cleaning Robots: How to Choose — Parameter, Function, and Application Comparison

If the primary task is cleaning 150–350 mm small-diameter and flat ducts in metro, high-speed railway, and other rail transit systems, the KT-956-D Crawler-Type Metro Duct Cleaning Robot should be the priority choice. If the requirement is to clean both central air conditioning main ducts and branch ducts, and one equipment set is expected to cover both robotic cleaning and flexible shaft cleaning, the KT-986 Combined Central Air Conditioning Duct Cleaning Machine should be evaluated first.

The KT-956-D Crawler-Type Metro Duct Cleaning Robot uses a compact crawler robot, mechanical rotating brush, dual cameras, and simultaneous vacuuming structure. It is mainly designed to solve equipment entry and internal cleaning problems in narrow ducts. The KT-986 Combined Central Air Conditioning Duct Cleaning Machine consists of two working modes: a main duct robot and a branch duct flexible shaft. It covers cleaning requirements for different duct configurations within the overall 100–800 mm range.

The two machines overlap in the 250–350 mm range, but their functional positioning is different. During procurement, the model should be determined based on actual duct inner width, inner height, cross-sectional structure, access openings, and project type—not solely on a single duct diameter figure.

1. What Are the KT-956-D and KT-986?

1.1 KT-956-D Crawler-Type Metro Duct Cleaning Robot

The KT-956-D Crawler-Type Metro Duct Cleaning Robot is a crawler-type robotic device designed for cleaning small-diameter and flat ducts.

The product uses a crawler travel mechanism and combines a mechanical rotating cleaning brush, dual cameras, LED lighting, a vacuum system, and remote control.

After the robot enters the duct, it moves forward on crawler tracks. The front-end cleaning brush mechanically brushes the duct walls, while the supporting vacuum system collects dust generated during cleaning. Operators can observe internal duct conditions through a display terminal and control equipment operation from outside the duct.

Main applications:

Metro ventilation ducts

High-speed railway and rail transit ventilation ducts

Small-diameter flat ducts

Some narrow central air conditioning ducts

Other small-to-medium ducts meeting equipment passage conditions

The KT-956-D has an applicable duct size of 150–350 mm, with a flat duct width requirement of ≥190 mm.

1.2 KT-986 Combined Central Air Conditioning Duct Cleaning Machine

The KT-986 Combined Central Air Conditioning Duct Cleaning Machine is a combined equipment set integrating main duct robotic cleaning and branch duct flexible shaft cleaning.

Its design focus is solving the problem of large size differences and different cleaning methods between main ducts and branch ducts in central air conditioning air systems.

The main duct uses robot mode: the robot enters the duct for mechanical brushing. The branch duct uses flexible shaft mode: the flexible shaft drives a cleaning brush deep into the duct, with a vacuum system collecting dust.

The equipment supports HD camera monitoring, real-time monitoring, video recording, photo capture, and host computer remote control.

Main applications:

Central air conditioning main ducts

Central air conditioning branch ducts

Rectangular and round ducts

Horizontal and vertical ducts

Ventilation systems in large public buildings and commercial buildings

Comprehensive duct projects requiring robot and flexible shaft coordination

The KT-986 has an overall applicable range of 100–800 mm, with the robot mode covering 250–800 mm and the flexible shaft mode covering 100–800 mm.

2. KT-956-D vs KT-986 Main Parameter Comparison

Note: The KT-986 flexible shaft speed and the KT-956-D cleaning brush speed are parameters of different working mechanisms and cannot be directly compared as the same indicator. The KT-986’s 2400W is the vacuum system power, not total equipment power.

3. What Are the Core Functions of the KT-956-D Crawler-Type Metro Duct Cleaning Robot?

The KT-956-D is designed around passage through small-diameter ducts, cleaning, and visual operation.

3.1 Compact Crawler Robot Suitable for Small-Diameter Ducts

The KT-956-D uses a crawler-type travel structure. The robot weighs approximately 6.2 kg.

Its applicable duct size is 150–350 mm, with a flat duct width requirement of ≥190 mm.

When the robot lifting arm is at its lowest position, dimensions are approximately 430 × 180 × 140 mm; at the highest position, approximately 400 × 180 × 260 mm.

For metro, high-speed railway, and other narrow ducts, the robot body width and height directly affect whether the equipment can pass through. Therefore, actual duct clear dimensions must be verified before purchase.

3.2 Mechanical Rotating Brushing with Vacuum System

The KT-956-D uses a mechanical rotating brush to clean inner duct walls. The cleaning brush speed is 148 rpm.

During cleaning, the brush head removes dust and particulate matter attached to the duct wall. The equipment is equipped with a 20 L vacuum cleaner and maximum airflow of approximately 2000 m³/h to collect dust generated during brushing.

The combination of mechanical brushing and simultaneous vacuuming helps reduce dust re-dispersion and re-deposition.

3.3 Dual Cameras and Lighting System

The KT-956-D is equipped with 3MP × 2 cameras, 4 sets of 2W LED lights, and a 10.1-inch display.

Operators can observe the area in front of the robot and internal duct working conditions, helping determine equipment position, duct conditions, and the cleaning process.

The equipment storage configuration is 4GB + 128GB, which can be used for relevant video and project data storage. The specific recording method is subject to the actual software configuration.

3.4 Remote Control and Crawler Travel

The KT-956-D has a travel speed of approximately 3.3 m/min, climbing capability of approximately 30°, and obstacle clearance capability of approximately 70 mm.

Operators control the robot from outside the duct through the control system, reducing the need for personnel to enter narrow ducts for prolonged cleaning.

3.5 Application Scenarios

The KT-956-D is mainly suitable for:

Small-diameter ducts in metro ventilation systems

Flat ducts in high-speed railway and rail transit systems

Narrow ducts that conventional large robots cannot enter

Duct cleaning projects requiring internal video observation

Small-to-medium ducts requiring mechanical brushing and simultaneous vacuuming

4. What Are the Core Functions of the KT-986 Combined Central Air Conditioning Duct Cleaning Machine?

The KT-986’s core advantage lies in combining robot and flexible shaft cleaning modes, making it suitable for projects with different duct diameters and configurations.

4.1 Main Duct Robotic Cleaning

The KT-986 main duct mode uses a robot that enters the duct for operation.

The robot’s applicable range is 250–800 mm. It uses 24V low-voltage power supply, has a travel speed of approximately 0.3 m/s, and a maximum climbing angle of 45°.

The main duct robot is equipped with a 1080P HD camera system and works with the brushing mechanism and vacuum system to complete internal mechanical cleaning.

For central air conditioning main ducts with larger dimensions and internal space meeting robot entry conditions, this method can be used for continuous operation.

4.2 Branch Duct Flexible Shaft Cleaning

The KT-986 flexible shaft mode has an applicable range of 100–800 mm and is equipped with a 15 m flexible brushing and vacuuming shaft.

The flexible shaft speed is 0–1000 rpm and supports forward and reverse rotation. The flexible shaft drives the cleaning brush to rotate and brush the inner duct walls.

For branch ducts that robots cannot suitably enter, small-diameter duct sections, and other ducts suitable for flexible shaft operation, the flexible shaft mode can be used.

4.3 Integrated Brushing and Vacuuming

The KT-986 uses dry mechanical brushing with simultaneous vacuuming. The vacuum system power is 2400W, with maximum airflow of approximately 2000 m³/h.

Whether using the robot or flexible shaft, the vacuum system can be used according to the corresponding configuration to handle dust generated during brushing.

4.4 HD Visualization and Remote Control

The KT-986 main duct robot uses 1080P HD camera, and the branch duct flexible shaft is equipped with HD visual camera configuration.

The equipment supports real-time monitoring, video recording, and photo capture, and uses host computer and remote control methods, facilitating observation of equipment working status and retention of construction process documentation.

4.5 One Equipment Set for Multiple Duct Configurations

The KT-986 can switch between robot and flexible shaft modes based on on-site duct configuration. It is suitable for rectangular ducts, round ducts, horizontal ducts, vertical ducts, main ducts, branch ducts, and other scenarios.

Actual usability still requires confirmation based on internal clear dimensions, bends, access openings, and equipment entry conditions.

5. How to Choose Between the Two Machines in the 250–350 mm Range?

This is the area most likely to cause questions during procurement.

The KT-956-D is applicable to 150–350 mm, and the KT-986 robot mode is applicable to 250–800 mm. The two overlap in the 250–350 mm range.

However, the same duct diameter does not mean the same equipment passage conditions.

For example:

For a 300 mm round duct, the round duct inner diameter and robot dimensions must be verified.

For a 300 mm rectangular duct, actual inner width and inner height must be confirmed.

For a flat duct with low height, robot body height must be carefully verified.

For ducts with reinforcing ribs, dampers, and localized obstacles, whether the robot can pass must be evaluated.

Selection recommendations:

If mainly cleaning metro and high-speed railway small-diameter flat ducts: prioritize the KT-956-D Crawler-Type Metro Duct Cleaning Robot.

If mainly cleaning central air conditioning main ducts: prioritize the KT-986 robot mode.

If the project includes both main ducts and branch ducts: prioritize the KT-986 combined robot and flexible shaft modes.

If duct configuration is special or dimensions are close to equipment limits: provide on-site dimensions and photos first for equipment adaptability confirmation.

6. Which Customers Are Suited to the KT-956-D and KT-986?

If the customer’s business is mainly concentrated in metro and rail transit small ducts, the KT-956-D is more targeted. If the customer undertakes central air conditioning duct projects in commercial buildings, hotels, hospitals, and large public buildings, the KT-986 combined structure is more worthy of attention.

7. What Technical Information Should Be Confirmed Before Purchasing the KT-956-D or KT-986?

To avoid problems such as inability to enter the duct or inability of the flexible shaft to reach the target position after procurement, prepare the following information before purchase.

1. Duct dimensions
Provide inner diameter, inner width, and inner height. Do not provide only external dimensions or nominal dimensions on drawings.

2. Duct type
Confirm whether it is a round duct, rectangular duct, flat duct, horizontal duct, or vertical duct.

3. Access opening dimensions
Check whether the robot can pass through the access opening. In particular, verify the KT-956-D robot body dimensions against the entry dimensions.

4. Internal duct structure
Provide information on bends, dampers, reinforcing ribs, supports, and transition locations.

5. Cleaning scope
Clarify whether the project is mainly small-diameter ducts or includes substantial main duct and branch duct workloads.

6. Cleaning method and documentation requirements
Confirm whether simultaneous vacuuming, real-time camera monitoring, video recording, photo capture, and construction documentation are required.

For ducts with special structures or dimensions close to equipment limits, on-site adaptability assessment should be conducted before determining the equipment.

8. Frequently Asked Questions (FAQ)

1. Which model has a larger applicable duct diameter, KT-956-D or KT-986?
The KT-956-D is applicable to 150–350 mm. The KT-986 has an overall applicable range of 100–800 mm, with the robot mode covering 250–800 mm and the flexible shaft mode covering 100–800 mm.

2. Can the KT-986 robot enter a 100 mm duct?
No. The KT-986’s 100–800 mm is the overall applicable range. The 100–800 mm corresponds to the flexible shaft mode. The robot mode applicable range is 250–800 mm.

3. Can the KT-956-D clean flat ducts?
Yes. The KT-956-D is mainly designed for small-diameter and flat ducts, with an applicable range of 150–350 mm and a flat duct width requirement of ≥190 mm. Actual clear height, entry dimensions, and internal obstacles still need to be verified.

4. Do both the KT-956-D and KT-986 have vacuuming functions?
Both machines use a combination of brushing and vacuuming. The KT-956-D is equipped with a 20 L vacuum cleaner. The KT-986 uses a 2400W vacuum system with maximum airflow of approximately 2000 m³/h.

5. Why does the KT-986 include both robot and flexible shaft?
Because central air conditioning main ducts and branch ducts have different structures. The robot is suitable for main ducts meeting entry and travel conditions, while the flexible shaft is suitable for some branch ducts and small-diameter duct sections that require deep cleaning from the access opening. Combining the two methods helps cover different duct sections within the same project.

6. Can the KT-956-D completely replace the KT-986?
No. The KT-956-D focuses on robotic cleaning of small-diameter and flat ducts. The KT-986 is designed for comprehensive main duct and branch duct cleaning. The working methods and project positioning of the two machines are different.

7. Can on-site information be provided before purchase to confirm equipment suitability?
Yes. It is recommended to provide duct inner diameter, width, height, access opening dimensions, site photos, and duct structure information. Technical personnel can assist in determining whether the equipment is suitable and which accessories need to be configured.

9. Conclusion: Confirm Duct Structure First, Then Determine Robot or Combined Cleaning Equipment

The KT-956-D Crawler-Type Metro Duct Cleaning Robot and the KT-986 Combined Central Air Conditioning Duct Cleaning Machine are designed for different engineering application requirements.

The KT-956-D uses a compact crawler structure, mechanical brushing, dual cameras, and simultaneous vacuuming, focusing on cleaning metro, high-speed railway, and other small-diameter flat ducts.

The KT-986 combines main duct robotic cleaning with branch duct flexible shaft cleaning, covering central air conditioning ducts of different dimensions and configurations through two working modes.

During procurement, it is recommended to first clarify the project type, duct internal clear dimensions, duct configuration, and construction requirements, then determine the equipment model. For ducts with overlapping dimensions or special structures, actual passage conditions and equipment configuration should be used as the basis.

Anhui Kuaitong Pipeline Cleaning Technology Co., Ltd.

Anhui Kuaitong Pipeline Cleaning Technology Co., Ltd., established in 2009, is a technology-oriented enterprise specializing in the R&D, manufacturing, and sales of pipeline cleaning, unclogging, and inspection equipment. The company is a National High-Tech Enterprise, a Technology-Based SME, a Training Base of the China Industrial Cleaning Association, and an Anhui Province Specialized and Sophisticated Enterprise. It has provided solutions to more than 23,000 domestic and international enterprises.

The company continuously develops cleaning, unclogging, and inspection equipment for central air conditioning air and water systems, industrial pipelines, boilers and heat exchange equipment, municipal pipelines, and other application scenarios, providing equipment and technical support for professional cleaning service providers, engineering companies, and industrial enterprises.

Website: www.kuaitonggroup.com
Technical Consultation (Phone/WhatsApp/WeChat): +86 18226181287

This document is compiled by the technical team of Anhui Kuaitong Pipeline Cleaning Technology Co., Ltd.