ZIMFLEX Publishes Industrial Hose User Manual

The manual is built on the technical data in the company's ZIMFLEX Product Specification Sheet (New Edition) and follows accepted industry practice for industrial hose worldwide.

Important notice This manual is a general technical guidance document. Specific technical data for each product - inside diameter, wall thickness, working pressure, vacuum rating, temperature range, certifications and so on - is governed by the corresponding Product Specification Sheet and the data published on the company website. All figures are approximate values measured at 23 °C and 50 % relative humidity, and will change with actual service conditions. ZIMFLEX reserves the right to revise specifications without prior notice.

1. Key Terms and Technical Parameters

Learning to read a specification sheet is the first step toward getting the selection right. The terms below appear throughout ZIMFLEX product documentation:

Term	Meaning and how to use it
Working pressure	The maximum pressure at which the hose may be used continuously at the stated temperature (23 °C, 50 % RH). As temperature rises, the permissible working pressure falls accordingly.
Burst pressure	The pressure at which the hose fails under short-term laboratory pressurization. It indicates the safety margin only - never treat it as a usable pressure.
Safety factor	The ratio of burst pressure to working pressure (for example, 3:1 for the 201P series). For critical or high-risk duties, choose a higher safety factor.
Vacuum rating	The maximum negative pressure the hose can withstand without collapsing or deforming under vacuum. Vacuum service requires a helical reinforcement such as steel wire or a plastic helix.
Minimum bend radius	The smallest radius at room temperature at which the hose will not kink or suffer a significant loss of pressure capability. Install with a radius larger than this value.
Wall thickness	The thickness of the hose wall. In abrasive material conveying, wall thickness directly determines wear life.
Temperature range	Both the media temperature and the ambient temperature must fall within this range. Short-term peak temperatures may slightly exceed the upper limit (the 903 series, for example, reaches +125 °C briefly), but sustained operation above the limit is not permitted.

Table 1-1 - Common terms and parameter definitions

2. Product Portfolio Overview

2.1 Six Product Families

ZIMFLEX organizes its industrial hose range into six families by application, covering most industrial duties - from abrasive powder conveying, chemicals and oils, and food and pharmaceutical service through to high-temperature fume extraction, antistatic hose and silicone hose.

Product family	Typical materials	Typical applications	Representative models
Abrasive material conveying hose	TPU	Granule and chip conveying, dust and wood-shaving extraction, sand and grit suction, vacuum loading and discharge	901, 903, 905P+, 906H, 909
Chemical, solvent and oil hose	UPE, NBR, EPDM, PVC, PA, TPV	Acid, alkali and solvent suction/discharge, oil transfer, welding and cutting gases, combined water/air service	201P, 202, 206, 207, 208, 937
Hose for food, beverage, pharmaceutical and cosmetic service	Food-grade PVC, PU, TPU, bio-based vinyl	Liquid food, fats and oils, potable water, alcoholic beverages, cosmetics	203, 205, 903F, 905F, 932
Ventilation, fume extraction and high-temperature hose	PVC, PP, TPE, EPDM-coated, nylon fabric	Ventilation and exhaust, fume extraction, automotive exhaust, high-temperature air discharge	501, 502, 950, 952, 953
Antistatic and conductive hose	Conductive PU, PE, PVC	Explosion-hazard areas, dust extraction, ventilation in conductive environments	954PE, 955, 956, 957
Silicone hose	Platinum-cured silicone	High-temperature steam, CIP/SIP cleaning, pharmaceutical, cosmetic and food service	ZS01–ZS14 series

Table 2-1 - Product family overview (see the ZIMFLEX Product Specification Sheet for the complete model list)

2.2 Common Reinforcement Constructions

Two hoses made of the same material can behave very differently. Pressure capability, vacuum resistance and flexibility depend heavily on the reinforcement, so specify material and construction together:

Helical steel wire reinforcement - excellent vacuum resistance; suitable for suction duty. Copper-plated or plastic-coated wire also provides antistatic performance, and the wire at the ends can be grounded.

Plastic helix (rigid helical PVC) reinforcement - lightweight and flexible with good crush resistance; widely used in ventilation, dust extraction and food-grade hose.

Fabric or textile braid reinforcement - higher pressure capability and a firmer hose body. Note, however, that hose reinforced with fiber cord alone can flatten or kink under vacuum or tight bends; avoid it for vacuum suction and discharge.

Dual reinforcement (steel wire plus braided mesh, double steel wire, etc.) - for heavy-duty service where pressure and abrasion resistance are both required, as in the 933 and ZS06.

Unreinforced hose - soft and transparent; limited to low-pressure drainage, ventilation or general transfer, such as the 930 series.

3. Selection Guide

3.1 The Five Selection Factors

Work through the following checklist in order. Miss any one of them and you risk premature hose failure.

(1) Media and chemical compatibility. Choose the tube material to suit the fluid or powder being conveyed: NBR, PU or TPU for oils; UPE or a PE liner for strong acids, alkalis and most solvents; platinum-cured silicone for high-temperature steam and hygienic service. Where chemicals are involved, always check the chemical resistance data for the material. If you cannot confirm compatibility, request a sample for a trial under real operating conditions, or contact ZIMFLEX technical support.

(2) Operating temperature. Both media temperature and ambient temperature must sit inside the hose's temperature range. Rising temperature significantly reduces pressure capability and service life - and when granules are conveyed at high velocity, frictional heat build-up must not be overlooked.

(3) Working pressure and pressure type. Distinguish between positive pressure, negative pressure (vacuum) and pulsating duty. Working pressure must not exceed the published figure, and a safety margin should be built in. Within a single series, the larger the bore, the lower the permissible working pressure - the 932 food-grade wire-reinforced hose, for example, is rated 8.5 bar at 6 mm ID, dropping to 4 bar at 102 mm and just 2 bar at 127 mm. Vacuum duty requires helical steel wire or plastic helix reinforcement, with the vacuum rating checked for each individual bore size.

(4) Bore size and flow rate. Calculate the inside diameter from the process flow rate and an economical flow velocity. Do not simply measure an old hose with calipers and extrapolate - the old hose may have been expanded at the coupling, or swollen overall under internal pressure. Choose the specification that is slightly smaller than, and closest to, the target bore.

(5) Bend radius and installation space. Where space is tight, choose a soft, small-bend-radius product. When conveying powders and granules, increase the bend radius to reduce elbow wear and avoid kinking and flow interruption.

3.2 Selection Notes for Special Operating Conditions

Special condition	Selection guidance
Abrasive media (sand, mineral powder, chips)	Select wall thickness by abrasion severity: 0.4 mm light duty → 0.6–0.9 mm medium duty → 1.2–2.5 mm heavy duty. A fully smooth bore (as in the 905P/906P) reduces material build-up and vortex wear.
Antistatic / explosion-hazard areas	Use only hose that is permanently conductive through the wall (955/956/957 series, surface resistance < 10⁴ Ω) and bond both ends of the steel wire to earth. Products meet TRBS 2153 / TRGS 727, ATEX and ISO 8031.
Food, beverage, pharmaceutical, cosmetic	Use certified food-grade models: FDA and EU 10/2011 compliant for food contact. For potable water, select models certified to KTW and W270 (such as the 931W). Never use industrial-grade hose for food. Where beverages with high alcohol content are conveyed, confirm the material's alcohol resistance.
High-temperature media or environments	Select by upper temperature limit: PU approx. 90 °C (high-temperature grades to 150 °C); TPE approx. 125–135 °C; platinum-cured silicone −40 to +220 °C; EPDM/PP-coated ducting hose up to 200 °C.
Vacuum / suction duty	Helical steel wire or plastic helix reinforcement is mandatory, with the vacuum rating verified per bore size. Textile braid hose collapses under vacuum and must not be used for suction or discharge under vacuum.
High-pressure transfer (cleaning, spraying)	Use dedicated high-pressure hose - 201P (16 bar), 931B40 (40 bar), 931B80 (80 bar) and similar - verified against a safety factor of at least 3:1.

Table 3-1 - Selection guidance for special operating conditions

3.3 Quick Reference: Representative Series

The table below is drawn from representative models in the ZIMFLEX Product Specification Sheet (New Edition) for fast orientation. Consult the relevant specification sheet for full details.

Model	Product name	ID (mm)	Temperature (°C)	Pressure and key features
903	PU hose, 0.6 mm wall, steel wire reinforced, medium abrasion resistance	25–356	−40/+90 (briefly +125)	Vacuum 0.03–0.2 bar; translucent, plasticizer-free and halogen-free
906H	PU hose, 1.5 mm wall, steel wire reinforced, high-temperature	-	150 °C	Heavy-duty abrasion resistance for hot abrasive duty
201P	Solvent-resistant suction/discharge hose, food grade, antistatic option	6.35–101.6	−30/+90	Working pressure 16 bar, safety factor 3:1; UPE liner resists 98 % of chemicals; FDA compliant
206	NBR nitrile rubber hose (extruded)	-	-	20 bar; oil transfer
932	Steel wire reinforced Bio Vinyl clear hose (food grade)	6–127	−10/+60	Working pressure 8.5 → 2 bar (falls as bore increases); FDA and EU 10/2011, mold resistant
903F / 905F	Food-grade PU hose with stainless steel wire reinforcement	-	-	304 stainless wire, EU food-grade certified; antistatic version available (FSS)
ZS03	Platinum-cured silicone hose with 304 stainless steel wire reinforcement	19–102	−40/+220	Translucent, FDA certified, resistant to high-temperature steam, suitable for CIP/SIP
950	Automotive exhaust hose	51–152	+200	EPDM/PP-coated polyester fabric, plastic helix reinforced, vacuum 0.05–0.31 bar
955	Conductive black PU hose (1.0 mm wall)	25–300	−40/+90	Smooth bore, working pressure 0.2–2.4 bar; surface resistance < 10⁴ Ω, ATEX / ISO 8031 compliant
951	Grey PVC dust extraction hose	-	-	Ultra-flexible for dust extraction and ventilation; flame-retardant grade 951FR also available

Table 3-2 - Quick reference for representative series (approximate values at 23 °C / 50 % RH)

3.4 Selection Process

Build the duty list: media name and concentration; temperature (media and ambient); working pressure and pressure type; flow rate and velocity; pipe routing and bend conditions; and any hygienic or explosion-protection regulatory requirements.

Shortlist materials and families by media and temperature (see Tables 2-1 and 3-2).

Check the specification sheet against pressure and bore: confirm that working pressure, vacuum rating and bend radius are all satisfactory at that bore size, and leave a safety margin.

Confirm certification and compliance (FDA, EU 10/2011, KTW/W270, RoHS, etc.).

Determine the connection method and coupling size. Where necessary, request samples and validate them under actual operating conditions.

If any doubt remains, call +86 400 680 7908 and a ZIMFLEX engineer will assist with selection.

4. Installation and Connection

4.1 Cutting

Cut square, holding the blade perpendicular to the hose axis. An angled cut prevents proper sealing and can cause leakage or coupling blow-off.

After cutting steel wire reinforced hose, the wire ends may be sharp. Smooth them with shears or pliers to prevent injury to personnel and damage to the coupling sealing face.

Remove burrs and debris from the cut end so that no foreign material enters the system.

4.2 Couplings and Clamps

Use couplings that match the hose bore. Never use a coupling with scored or corroded surfaces.

When using ZIMFLEX bridge-type hose clamps on corrugated hose, the bridge section must sit over the crest of the corrugation, bearing on the highest point of the reinforcement, while the band seats into the valley. For hose above 25 mm ID, two clamps are recommended for a more secure connection.

Tighten clamps properly. Over-tightening cuts into the wall and can cause rupture; under-tightening leads to leaks and blow-off. Never substitute wire or similar improvised bindings for a proper clamp.

Do not use rigid-pipe quick-connect (push-in) fittings on hose - they can cause the hose to burst.

In hygienic food and pharmaceutical service, use sanitary fittings such as Tri-Clamp (TC), SMS or Type C couplings with matching gaskets.

4.3 Routing and Layout

Keep the actual bend radius larger than the published minimum. Over-bending damages the hose and reduces its pressure capability.

Avoid installing hose under torsional load. Allow enough slack to absorb equipment vibration, thermal expansion and movement.

Keep hose away from heat sources and open flame. Fit protective sleeves where it passes sharp edges or abrasion points, and prevent it from being run over by vehicles or material handling equipment.

When conveying flammable media or dust, the steel wire at both ends of a conductive hose must be reliably grounded.

After installation, pressure-test at approximately 1.25 × working pressure. Confirm there is no leakage and no abnormal deformation before putting the line into service.

5. Storage and Handling

Hose is a polymer product. Poor storage accelerates ageing - surface tackiness, cracking and hardening - and shortens service life even before the hose is ever used. Observe the following:

5.1 Storage Environment

Store indoors in a cool, dry, well-ventilated area. Protect from direct sunlight and rain - UV radiation is the main cause of surface degradation and cracking.

Keep away from ozone sources (electric motors, welding machines and high-voltage equipment generate ozone in operation), sparks and high-temperature heat sources.

Do not store alongside oils, solvents, acids, alkalis or their vapours, which can cause swelling and deterioration.

Avoid temperature extremes; store at room temperature with moderate relative humidity.

5.2 How to Store

Keep hose in its original packaging wherever possible. If coiling is necessary, coil naturally with a coil diameter clearly larger than the hose's minimum bend radius, so that tight coiling does not cause permanent deformation.

Do not hang hose on nails or hooks - localized support stress causes permanent deformation.

Do not stack flat coils too high, to avoid crushing the bottom layers. Never place heavy objects on hose.

Drain and dry hose before storage, and cap the ends to keep out dust, insects and other contamination.

Long lengths stored straight should be kept free of kinks and dead bends.

5.3 Inventory Management

Apply first-in, first-out (FIFO) rotation so hose is not held beyond its intended storage life.

Inspect stored hose regularly - quarterly is recommended. Cracking, tackiness, discoloration or deformation should be assessed and dealt with promptly.

Before using hose that has been in storage for a long time, re-inspect it and, where necessary, pressure-test it before putting it into service.

Keep inbound and outbound records covering batch, storage date and location for traceability.

6. Operation and Maintenance

6.1 Pre-Use Checks

Confirm that the model and specification match the actual duty (media, temperature, pressure, bore, certification).

Inspect the appearance: cracking, deep scoring, bulging, hardening, swelling or twisted deformation.

Check couplings and clamps: couplings free of corrosion and damage; clamps of the correct size and properly tightened; hose fully inserted to the required depth.

For critical duties, pressure-test before use to confirm there is no leakage and no abnormal deformation.

6.2 During Operation

Never exceed the temperature or pressure limits. When operating near the upper temperature limit, reduce working pressure accordingly (temperature–pressure correction data is available from ZIMFLEX on request).

Avoid water hammer and pressure shock. Open and close valves slowly to prevent instantaneous pressure spikes from damaging the hose.

Powder and granule conveying accelerates bore wear. Increase bend radius, control flow velocity, and pay particular attention to elbows and other wear-prone areas. Rotate the hose periodically so that wear is distributed evenly.

Prevent fluid from penetrating between the coupling and the reinforcement layer: ingress into the reinforcement causes deterioration, and in food service it encourages bacterial growth. If ingress is found, take the hose out of service immediately.

Conductive and antistatic hose must remain continuously and reliably grounded at both ends, with the ground resistance tested periodically.

Do not drag hose across the floor when moving it, and protect it from vehicle run-over and sharp objects.

6.3 Periodic Inspection and Retirement Criteria

Hose life depends largely on the nature of the fluid, temperature, flow velocity, the frequency of pressurization and depressurization, and the degree of wear. It cannot be defined by a fixed period, so periodic inspection is essential. ZIMFLEX recommends a visual check before each shift, plus weekly or monthly inspections scheduled according to duty. If any of the following is found, stop using the hose immediately and replace it:

Inspection area	Warning signs	Action
Near the coupling	Local elongation, abnormal bending, leakage, bulging, or reduced insertion depth	Take out of service and replace immediately
Outer surface	Deep scoring, cracking or crazing, water ingress into or exposure of the reinforcement	Take out of service and replace immediately
Inner surface	Lining separation, bulging, or wear exposing the reinforcement (flaking material and reinforcement fragments can contaminate the fluid)	Take out of service and replace immediately
Overall condition	Obvious hardening, swelling, discoloration or abnormal deformation	Take out of service and replace immediately
Connection	Loose or corroded clamps, damage to the coupling sealing face	Re-tighten, or replace the coupling/clamp

Table 6-1 - Periodic inspection and retirement criteria

6.4 Cleaning and Sanitizing

Choose the cleaning method and agent to suit the hose material. Never scrape the bore with wire brushes or other hard tools.

CIP cleaning of food-grade hose: silicone hose can be cleaned by short-term circulation of a 2 %–3 % diluted alkaline solution (such as caustic soda). Be aware that deterioration is markedly faster than with clean water and air, so shorten inspection and replacement intervals accordingly. Higher concentrations accelerate deterioration.

Steam cleaning temperature must not exceed the hose's upper temperature limit. After cleaning, drain thoroughly and dry before storage.

6.5 Service Life and Preventive Replacement

For critical positions in continuous production, or where the safety risk is high, establish a preventive replacement interval based on historical inspection data. Record the installation date, duty and results of every inspection for each hose, so that replacement happens on schedule or at the first sign of a problem - leaving no hidden risk in the line.

7. Safety Warnings

Warning - failure to observe the following prohibitions may result in personal injury or property damage. These apply to all ZIMFLEX industrial hose products.

Do not use hose for fluids outside the range permitted in the specification sheet. Conveying flammable gas, steam, fuel oil or other special media must first be confirmed with ZIMFLEX, and a dedicated product must be selected.

Non-food-grade hose must never be used to convey food, beverages or cosmetics.

Do not use the hose for medical implants, injection or any other application involving contact with the human body.

Hose must not come into direct contact with, or be placed close to, open flame.

Do not use general industrial hose as a load-bearing, lifting or towing component. (Hose designed for vacuum lifters, such as the 601 series, must be used strictly within its rated lifting capacity.)

If a pressurized line behaves abnormally (leakage, bulging), personnel must evacuate the area and depressurize before taking any action. No one may stand within the swing radius of a hose.

Dispose of scrap hose as industrial waste in accordance with local regulations. Do not incinerate - burning may release hazardous gases.

8. Frequently Asked Questions

Q1. I measured the old hose at about 20 mm ID with calipers. Can I just buy 20 mm ID hose? We do not recommend it. The old hose may have been expanded by the coupling, or swollen overall under internal pressure, so measurements often differ from the true specification. Compare against the specification table and choose the size slightly smaller than, and closest to, your target bore. If you are unsure, contact ZIMFLEX to confirm.

Q2. Does a smaller minimum bend radius mean the hose is more flexible? Not necessarily. Minimum bend radius is only one indicator of flexibility; wall thickness, material and reinforcement all affect how the hose feels in the hand. Consider deformation data and physical samples together.

Q3. The hose kinks or flattens in service, changing the flow or stopping it altogether. What should I do? Hose reinforced with fiber cord alone flattens easily under tight bends or vacuum. Switch to a helically reinforced hose with steel wire or a plastic helix - these constructions resist kinking and crushing, and can also be used under vacuum.

Q4. Can silicone hose be cleaned with caustic soda? High-concentration alkali degrades silicone and must not be used. For CIP purposes, a solution diluted to 2 %–3 % may be used briefly, but deterioration is faster than with clean water and air, so inspection and replacement intervals must be shortened.

Q5. How can I extend hose life in abrasive service? Combine the following measures: increase the bend radius and reduce conveying velocity; choose a heavier wall or a fully smooth-bore model; rotate the hose periodically to even out wear; and protect or pre-stock the elbows where wear concentrates.

9. Technical Support

For any technical question regarding selection, installation or operation, contact the ZIMFLEX technical service team at +86 400 680 7908. Services include chemical resistance verification, sample trials, on-site duty analysis and coupling selection.

Supporting documentation: ZIMFLEX Product Specification Sheet (New Edition) - complete parameters for all six families: chemicals/solvents/oils; food/beverage/pharmaceutical/cosmetic; abrasive material conveying; ventilation, fume and high temperature; antistatic and conductive; and silicone hose.

About ZIMFLEX

ZIMFLEX manufactures industrial hose for abrasive material conveying, chemical, solvent and oil transfer, food, beverage, pharmaceutical and cosmetic service, ventilation and high-temperature fume extraction, antistatic and conductive applications, and platinum-cured silicone hose. The company provides technical support covering hose selection, chemical compatibility verification, sample trials and coupling specification.

Contact: +86 400 680 7908