RTP pipe specifications describe three things: what the liner is made of, what carries the pressure, and what protects the pipe from the outside world. A reinforced thermoplastic pipe specification sheet then ties those layer choices to a size, a pressure rating, a temperature basis and a spool length. This guide explains how to read reinforced thermoplastic pipe specifications layer by layer, which questions to ask about each material choice against your pressure, temperature and medium, and which fields a datasheet has to fill in before two offers can be compared.
It is a reading guide, not a selection guide. Whether RTP belongs on a given line at all is covered in RTP Pipe Selection: When Reinforced Thermoplastic Pipe Fits Gathering Service (RFQ Fields). Here RTP is already on the shortlist and the task is to read, or write, the specification.
How to read an RTP spec sheet
Start with what the product page gives you and what it deliberately leaves to the datasheet. The CNPS Reinforced Thermoplastic Pipe (RTP) page describes RTP as a flexible composite line pipe with a thermoplastic liner, a reinforcement layer and a protective jacket. It states that capability depends on the exact liner, reinforcement, cover, end fittings, size and qualification, and that the word “RTP” does not by itself prove a pressure, temperature, chemical-compatibility or API rating. The label names a construction family; the values belong to one configuration.
| Spec-sheet field | What the CNPS product page states | What the datasheet must add |
|---|---|---|
| Construction | Thermoplastic liner, load-bearing reinforcement, outer protective cover; extra layers or tapes possible | The offered cross-section, layer by layer |
| Liner | A thermoplastic liner that contains the fluid | Polymer grade and its compatibility and permeation limits for your medium |
| Reinforcement | May use polymer fibres, glass, aramid, steel or another qualified construction | The reinforcement actually offered for each size and pressure class |
| Cover / jacket | Protects the reinforcement in manufacture, transport, installation and service | Material and the exposures it is qualified for |
| Pressure and temperature | No single headline rating; ask for the qualified pressure-temperature relationship | Rated pressure at the design temperature for each size |
| Bend radius, reel, length | Must be planned; confirmed from the product data | Minimum bend radius, reel dimensions and length per reel for each size |
Any value the product page does not state, such as wall thickness, liner grade, bend radius or the rating of a given diameter, comes from the manufacturer datasheet per size. If a value is missing from an offer, ask for it rather than borrowing a figure from another size or another supplier.
Liner: medium and temperature compatibility questions
The liner is the only layer that touches the fluid, so the RTP material question starts here. HDPE is a common liner polymer; other liner polymers exist across the industry, and each grade has its own chemical and temperature limits. Read the liner entry on a spec sheet against four questions:
- Medium. Is the liner grade stated as compatible with the full fluid: water chemistry, hydrocarbons, CO₂, H₂S where present, solids and every chemical you dose or use for cleaning?
- Temperature. At what fluid temperature does the liner keep the stated rating? Thermoplastics lose strength and gain permeability as temperature rises, so the liner often sets the temperature basis for the whole pipe.
- Gas and permeation. If the line carries gas or a gas fraction, does the datasheet state permeation considerations and any limits on fast depressurisation?
- Change control. Is the liner grade fixed for the order, or can it change between quotation and manufacture? A change of liner polymer can change the qualification basis.
A liner named only by a family term, with no grade and no compatibility statement for your medium, is incomplete.
Reinforcement options: polymer fibre, glass, aramid and steel
The reinforcement carries pressure and the other mechanical loads. The CNPS product page lists polymer fibres, glass, aramid, steel or another qualified construction. The page does not say which reinforcement goes with which pressure class, and neither should a guide. That pairing is set by the manufacturer’s qualification for each size, so ask the same questions of every option:
| Reinforcement | Ask the datasheet to state |
|---|---|
| Polymer fibre | Fibre type, rated pressure per size at the design temperature, and the long-term and cyclic test basis behind it |
| Glass fibre | Rated pressure per size, the temperature basis, and any limits from the medium or from water exposure if the cover is damaged |
| Aramid | Rated pressure per size, the temperature basis, and the bend radius and handling limits that go with it |
| Steel wire or strip | Rated pressure per size, corrosion protection of the steel layer, and how the cover keeps it isolated from external water |
Two offers with the same diameter but different reinforcement are different products. Compare them on the qualified pressure-temperature envelope for your size, not on the reinforcement name. What “qualified” means under API Specification 15S is covered in API 15S RTP: What the Spec Covers, What a Certificate Proves, and How to Ask for It in an RFQ.
Outer jacket: UV, abrasion, burial and trenchless pulls
The jacket, also called the cover, protects the reinforcement during manufacture, transport, installation and service. Its spec-sheet entry should match the route, not a generic default:
- Surface-laid lines: ask whether the jacket is stated for long-term UV exposure and the ambient temperature range on site.
- Buried lines: ask for the backfill and trench conditions the jacket and pipe are rated for, and the damage criteria for scratches found at installation.
- Trenchless pulls and conduits: ask for the allowable pull force, abrasion behaviour and any requirement for a sleeve or conduit liner.
A damaged jacket can expose the reinforcement, so the spec sheet should state repair or acceptance criteria, not only the material.
Size, pressure and temperature: why the size-specific rating governs
Questions about RTP pressure usually look for one number; a spec sheet rarely works that way. A headline figure is a family envelope, often the best case across sizes at a stated reference temperature. The rating that governs your line is the rated pressure for your diameter at your design temperature, with your reinforcement, from the manufacturer datasheet per size.
The CNPS product page asks for the qualified pressure-temperature relationship rather than a single headline rating, and ratings are issued per size, so read three things together:
- Diameter: the internal diameter, or the hydraulic performance you need, and the nominal size the datasheet uses.
- Pressure basis: the rated pressure for that size, and whether it covers surge, cycling and vacuum or only steady operation.
- Temperature basis: the minimum and maximum temperatures at which that rating applies, for the fluid and for the ambient conditions.
The pipe body is not the whole pressure system: the end fitting can cap the system rating below the pipe body.
Spool length, reel and logistics fields
RTP is delivered on reels or in coils, so length is a specification field, not only a logistics detail. The CNPS product page notes that long reel lengths reduce field joints but that reel dimensions, transport limits, minimum bend radius, pull forces and termination work must be planned. On the spec sheet, look for:
- length per reel or coil for each size, and the number of reels for the route;
- reel dimensions and loaded weight against road, bridge and site-access limits;
- minimum bend radius for storage, payout and installed condition;
- storage conditions and any limits on time in sunlight or cold before installation;
- the payout equipment and handling attachments the method statement assumes.
How the reel decision compares with TCP and API 17J flexible pipe is covered in RTP vs TCP vs API 17J Flexible Pipe: Which Spoolable Line Fits Your Flowline.
RTP spec fields to request with an enquiry
To get spec sheets you can compare, ask every supplier to return the same construction fields for each size. This list covers the pipe-body specification only; the line-by-line enquiry for a gathering system is in the RTP selection guide linked above.
| Field | What to ask for | Why ask |
|---|---|---|
| Cross-section | Every layer of the offered construction, including tapes | Offers with the same name can differ layer by layer. |
| Liner | Polymer grade; compatibility and permeation statement for your medium | The liner alone touches the fluid and often sets the temperature limit. |
| Reinforcement | Type for each size and pressure class | A different reinforcement makes a different product, even at the same size. |
| Jacket | Material; UV, abrasion, burial and pull exposures covered | A damaged jacket can expose the reinforcement on your route. |
| Rating | Rated pressure per size at the design temperature; cyclic and surge basis | A pressure rating cannot be compared without its temperature and loading basis. |
| Temperature | Minimum and maximum fluid and ambient temperatures for that rating | The same pipe carries a lower rating as temperature rises. |
| Geometry | Internal diameter, wall build-up and minimum bend radius per size | Bore sets hydraulics and bend radius sets handling and routing. |
| Supply | Length per reel, reel dimensions and weight, storage limits | Reel size decides transport, site access and the number of field joints. |
| Evidence | Qualification reference covering the exact configuration offered | A qualification only counts if it covers the exact configuration offered. |
CNPS supplies API 15S certified RTP. Ask for the certificate copies with the offer and check which sizes and configurations they cover against the fields above.
FAQ
What do RTP pipe specifications include?
The liner polymer, the reinforcement type, the jacket material, the size and wall build-up, the rated pressure at a stated temperature, the minimum bend radius and the length per reel, each tied to one configuration.
Which RTP material is best?
None is best in general. The liner has to suit the medium and temperature, the reinforcement has to carry the rated pressure for your size, and the jacket has to suit the route. Compare offers for the same duty.
Does the reinforcement type decide the pressure rating?
It is one input. The rated pressure also depends on the diameter, the layer build-up, the temperature and the qualification of that exact configuration, so take it from the manufacturer datasheet per size.
Why does the CNPS product page not list one pressure rating?
Because a single headline figure cannot cover every size, temperature and medium. The page asks for the qualified pressure-temperature relationship of the configuration offered, which is what you should compare.
Is “reinforced thermoplastic pipe RTP” the same as TCP?
No. TCP terminology and bonding architecture vary by manufacturer, so read the defined construction and qualification rather than the label. The RTP vs TCP vs API 17J page linked above compares them.
Where do I check the API 15S side of a specification?
On the API 15S RTP page linked above, which explains what the specification covers and what a certificate proves. Keep this page for reading the construction fields.
If you have an RTP specification to check against your pressure, temperature and medium, Talk to an Engineer with the fields above. Send the medium, the design pressure and temperature, the sizes and lengths, the route conditions and the evidence you expect, and we will review which configuration fits.
