Bell Plastics Limited
Bell designs and manufacturers plastic hose mandrels, which are long, high-specification rods used by the manufacturers of hydraulic and other industrial hoses in their own manufacturing processes.
Bell Plastics has focused on the rubber hose industry ever since the company was founded over 30 years ago and as a consequence has deep understanding and expertise within this field.
Bell Plastics has a dedicated laboratory where it is able to test customers’ products and then offer technical solutions to overcome hose production problems.
The range of advice can vary from helping new and existing customers select and switch to a new type of mandrel, through to advising how to improve performance and life of the mandrel.
Bell Plastics focuses on mandrels made from various types of plastic, but primarily nylon, using a proprietary highly automated extrusion process which results in superior mandrel properties and performance. Bell uses a unique, specially-designed production technology that guarantees very low dimensional variability and a complete absence of internal voids or holes in its mandrels. These defects are frequently present in lower-quality competing mandrels produced by conventional extrusion processes, and can lead to defects and inconsistencies in the customer’s finished hose.
To cope with increasing demand, Bell Plastics expanded its facilities in August 2017 through taking on additional factory space and by adding new extrusion lines to increase capacity by 33% during 16-17. Further extrusion lines have now also been added in 2017 which have increased capacity by another 20%.
The customers for Bell Plastics’ mandrel and film products range from large multi-national rubber products companies to local/regional hose producers. All of its mandrel and film products are exported, predominantly to the USA, continental Europe, South Asia and the Far East.
Hose mandrels are long, high-specification rods around which reinforced industrial rubber hoses are formed. Examples of such mandrel-made hoses include hydraulic hoses, high-pressure water hoses, air-conditioning hoses and power steering hoses.
The mandrel determines the critical internal diameter of the hose, and supports the rubber of the hose as its steel wire or fabric reinforcements are applied during production. Once the rubber hose has been formed and vulcanized, the mandrel is removed by high pressure water, and is re-used, typically for 10-20 cycles.
Dimensions of Bell mandrels vary from 3mm to 50mm in diameter, and up to 2km in length supplied in coils or on drums.
Bell Plastics make mandrels from nylon, polyproylene, thermoplastic elastomers and TPX to its customers’ individual requirements.
Bell Plastics produces a range of mandrel lubricants, which have been developed specifically for hose production.
Mandrel lubricants are applied to flexible mandrels to improve mandrel ejection, to minimise ejection time and reduce water pressure so eliminating tube damage and mandrel damage.
Bell Plastics Ltd produces only water based mandrel lubricant eliminating risk of flammable solvents and environmental damage.
Bell Plastics produces protective films for abrasion and chemical resistance.
The two types of film Bell Plastics manufacturers, XLPE (cross-linkable polyethylene) and UHMWPE (ultra-high molecular weight polyethylene), are used as chemically-resistant inner linings and abrasion-resistant outer coverings of industrial hoses. Typical applications include the internal lining of chemical transfer hoses, e.g. tanker discharge hoses.
Both films are highly abrasion-resistant and have low friction properties and are therefore also used by Bell Plastics’ customers to make wear-resistant coverings on industrial and high-pressure hoses, such as mining hoses and hydraulic hoses on diggers and earth-moving equipment.
Bell’s other products include:
- Safetytread, a business specialised in manufacturing anti-slip stair treads, inserts and nosings for use in commercial and public buildings
- Coating of wire and wire rope with a variety of plastics materials.
- Exceptional quality of nylon mandrels used for spiral reinforced and large diameter braided hose
- Leading range of technical solutions for hose mandrels
- Technical service for hose manufacturers with mandrel needs
- Bell Plastics’ production equipment is designed and built by Bell Plastics to its own specifications, providing a substantial barrier to entry for would-be competitors seeking to make mandrels of equivalent quality
Benefits of nylon mandrel
Mandrels can be made of steel, rubber, polypropylene (PP) and nylon, as well as other materials. The type of mandrel material used has a significant impact on the hose manufacturer’s production process, which is designed to suit the flexibility and other characteristics of the mandrel material. This results in difficulties for hose producers to switch between mandrel materials.
Bell Plastics is a leader in the production of nylon mandrels, which have several benefits over other types of mandrel.
- They are more flexible than metal and PP mandrels, giving the hose producer greater production efficiencies
- They can typically be re-used more times than PP and rubber mandrels and are easier to join together into long defect-free production lengths
- They are easier to extract from the hose
- They can be re-used more times than PP and rubber mandrels
These characteristics all help to reduce hose-makers costs and make nylon the mandrel of choice.
The market for industrial rubber hose is growing approximately in line with GDP in the relevant markets. Bell estimates that there are approximately 300 hose plants worldwide of which approximately half use some form of mandrel for hose formation. The estimated total mandrel market size is +£20m.
There are no other significant specialist producers of nylon mandrel supplying the hose industry. The key competition comes from in-house production of mandrels, from the rubber hose manufacturers or from local, non-specialist producers making plastic mandrel as part of a wide range of other extrusions.
The type of mandrel material used has a significant impact on the hose manufacturer’s production process – this results in barriers to switching mandrel type and provider.