PFM Screen's Seamed Press Felt is an on-machine seamable papermaking press felt that can be threaded through the press section and closed on the machine — eliminating the need to lift a full-width felt overhead by crane. Available with pin seam or spiral seam construction, in single, double, or multi-layer base structures suited to any press type from plain roll to shoe press.
Description
PFM Screen's Seamed Press Felt is an on-machine seamable papermaking press felt designed for press positions where endless felt installation is impractical, unsafe, or too time-consuming. Unlike an endless felt — which must be lifted over the full width of the machine and threaded in a single piece — a seamed felt can be fed into the press section as a flat strip and its ends joined on the machine via a pintle-wire seam. This approach cuts installation time from hours to minutes, eliminates the need for heavy lifting equipment across the full machine width, and significantly reduces the manpower required for a felt change.
 | How On-Machine Seaming Works 1. The felt is manufactured with seam loops or coils on each end instead of being woven endless. 2. The felt is pulled through the press section as a flat strip while the machine is open. 3. The two ends are brought together, loops interlocked, and a stainless-steel pintle wire inserted to lock the seam closed. 4. The seam is now a continuous loop — the machine can be closed and restarted. |
 Pin Seam The machine-direction yarns of the base are formed into loops at each end of the felt. When the two ends are brought together, the loops interlock and a pintle wire is inserted through all the loops to form a closed seam. Best for: Medium to high-speed machines, most press types. High seam tensile strength, reliable, widely used. |  Spiral Seam Coiled plastic spiral strips are attached to each end of the felt. The spirals from each end mesh together and a pintle wire is inserted through the interlocked spirals to form the seam. Best for: Machines where extremely uniform seam geometry is required, or where very high lateral stability across the seam zone is needed. |
| Property | Endless Press Felt | Seamed Press Felt (This Page) |
|---|---|---|
| Installation method | Crane lifts full width overhead | Thread flat through press, seam on-machine |
| Installation time | 2–8 hours (depending on machine) | 30–60 minutes (seam takes minutes) |
| Crane required | Yes — full machine width | No — thread flat |
| Safety risk | Overhead lift hazard | Much reduced |
| Manpower needed | 4–8 people | 2–3 people |
| Seam mark on paper | No seam mark | None when correctly specified |
| Machine suitability | All machines where crane access possible | All machines, including confined crane-access |
| Felt tensile at seam | Full felt tensile throughout | ≥80% of base felt tensile |
Specify Your Seamed Press Felt — Quote Within 24 Hours Share your press type, machine type, paper grade, machine speed, and felt dimensions. PFM Screen recommends the right seam type, base structure, and GSM, and issues a full specification within one business day. WhatsApp: +86 153 6967 9157Email: polyestermesh@pfmscreen.com |
Feature
PFM Screen's Seamed Press Felt delivers all the dewatering performance of an endless press felt while eliminating the installation complexity, safety risk, and crane dependency of full-width felt change. The on-machine seam is engineered to match the properties of the surrounding felt — with seam tensile strength ≥80% of the base felt, and seam geometry designed to pass through the press and under the paper sheet without leaving any trace mark.
01 Safe, Fast Installation No overhead crane lift required for the main felt. Thread flat through the press section; close the seam on-machine in minutes. Full felt change in 30–60 minutes instead of 2–8 hours. | 02 Excellent Runnability PFM Screen seamed felts run smoothly from startup — the seam zone is engineered to match the felt body in permeability, surface texture, and structural rigidity, producing no disturbance to the paper sheet as the seam passes through the nip. | 03 Good Water Removal The base structure of the seamed felt — single, double, or multi-layer as specified for the press position — delivers the same void volume and drainage performance as its endless equivalent. Seaming does not compromise the dewatering capacity. | 04 Adjustable Void Volume The base structure of the seamed felt can be specified in single-layer, double-layer, or multi-layer construction — allowing void volume, GSM, and permeability to be matched to the press type, NIP load, and paper grade requirements. |
● Pin seam or spiral seam — two seam types available, both with pintle-wire closing mechanism ● Seam tensile ≥80% of base felt — seam does not limit the felt's tensile performance in normal press operation ● Mark-free running when correctly specified — seam geometry and surface engineered to leave no impression on the paper sheet ● Single, double, or multi-layer base — full range of base constructions available in seamed version | ● Virgin or recycled fiber furnish — seamed felts perform equally on virgin and recycled fiber-based paper grades ● Reduced felt change downtime — faster installation means shorter planned downtime windows for press clothing changes ● Reduced manpower requirement — 2–3 people vs 4–8 for endless felt installation ● Fits all major paper machine types — fourdrinier, cylinder, multicylinder, gap former, tissue; all press positions |
≥2500 N/5cm Tensile Base felt tensile strength | ≥80% Seam Tensile Ratio Seam tensile vs base felt tensile | 30–60 Min. Installation vs 2–8 hours for endless felt | Zero Mark Defects When correctly specified for grade & speed |
Application
PFM Screen's Seamed Press Felt is specified when installation logistics, safety requirements, or machine design make endless felt installation impractical. The seamed format is equally applicable to all press types and paper grades — the choice of seam type and base construction allows it to be matched to any press section requirement from plain roll to shoe press.
Restricted crane access The press section is located where overhead crane access is limited, obstructed, or unavailable — making full-width felt lifting impractical or impossible. | Safety programme requirement The mill's safety programme restricts overhead lifts above the machine width, or the insurance requirements favour reduced overhead lift operations. | Reduced downtime target The production target requires the felt change to be completed within 30–60 minutes — achievable with seamed installation but not with endless felt installation. | Reduced manpower The felt change crew has been reduced and the available manpower is insufficient for an endless felt installation — seamed installation requires only 2–3 people. |
| Press / Machine Type | Compatible | Notes |
|---|---|---|
| Plain roll press | ✓ | Single-layer base seamed felt — easiest application; seam passes cleanly through plain roll nip |
| Nip roll press | ✓ | Pin seam or spiral seam; matched to press NIP load |
| Vacuum suction press | ✓ | Double-layer base seamed felt; seam construction must be compatible with vacuum load |
| Groove roll press | ✓ | Pin seam or spiral seam; double-layer base for mark resistance |
| Blind-hole press | ✓ | Double-layer base recommended; seam tensile and geometry confirmed per NIP load |
| Large-diameter roll press | ✓ | Double or multi-layer base seamed felt for extended nip dwell time |
| Cylinder machine press | ✓ | Traditional cylinder machines — seamed felt installation is especially advantageous in tight machine rooms |
| Fourdrinier press section | ✓ | All fourdrinier press positions; seamed format reduces downtime for all scheduled felt changes |
| Shoe press | △ | Contact PFM Screen for confirmation — seam integrity at sustained ≥200 kN/m must be confirmed per application |
≤1000 m/min Max. machine speed | All Grades Virgin or recycled fiber | ≥80% Seam tensile ratio | 2 Types Pin seam or spiral seam |
| Paper Grade | Basis Weight | Base Structure | Seam Type |
|---|---|---|---|
| Tissue / sanitary paper | 8–35 g/m² | Single layer | Pin seam |
| Writing & printing paper | 50–120 g/m² | Single or double layer | Pin seam or spiral seam |
| Newsprint | 40–52 g/m² | Single or double layer | Pin seam |
| Kraft & packaging paper | 60–150 g/m² | Single or double layer | Pin seam |
| Corrugating medium | 80–180 g/m² | Double layer | Pin seam |
| Paper board | 150–400 g/m² | Double or multi-layer | Pin seam or spiral seam |
| Technical / specialty paper | 40–200 g/m² | Single or double layer | Pin seam or spiral seam |
| OEM Brand | Machine Types | Notes on Seamed Felt Fit |
|---|---|---|
| Valmet | OptiPress, SymPress, TissueFlex, ValPress | All press positions — seamed felt supported on all standard Valmet configurations |
| Voith | DuoFormer, NipcoFlex, TF series | All press positions; seam specification confirmed per NIP load |
| Andritz | PrimePress, Gap Former | All press positions; seam type selected per press geometry |
| GL&V / Kadant | Fourdrinier and cylinder machines | All press positions — seamed felt advantageous in older, lower-headroom machine rooms |
| Chinese domestic OEMs | All machine types | Particularly useful on older machines with limited crane access or confined machine rooms |
Specifications
GSM 800–1600 g/m² Depends on base structure (single/double/multi-layer) | Tensile Strength ≥2500 N/5cm Base felt; seam tensile ≥80% of this value | Elongation ≤0.8% Under standard press load conditions |
Seam Types Pin Seam / Spiral Seam Both with stainless-steel pintle wire closing | Air Permeability 25–120 CFM Adjusted per base structure and press type | Max. Machine Speed ≤1000 m/min Contact PFM Screen for higher-speed confirmation |
PFM Screen's Seamed Press Felts are custom-engineered products. Base structure, GSM, seam type, and permeability are all specified per machine and press position. Contact PFM Screen with your machine and press details for a specific model recommendation, full data sheet, and formal quotation within 24 hours.
Q1: What is a seamed press felt and how does it differ from an endless press felt? A seamed press felt (also called an on-machine seamable press felt) is a press felt that is manufactured with seam loops or coils at each end instead of being woven into a continuous loop. To install it, the felt is threaded through the press section while lying flat — no crane lift over the machine width is needed — and the two ends are joined on the machine by inserting a pintle wire through the interlocked loops or spirals. An endless press felt, by contrast, is woven as a continuous loop and must be lifted over the full machine width by crane, then threaded as a loop. The seamed felt offers the same dewatering performance as an endless felt but with installation times of 30–60 minutes versus 2–8 hours and significantly reduced manpower and crane requirements. |
Q2: What types of seams are used in PFM Screen's seamed press felts? PFM Screen's seamed press felts are available with two seam types: pin seam and spiral seam. In a pin seam, the machine-direction yarns of the base fabric are formed into loops at each end of the felt — when the two ends are brought together, the loops interlock, and a stainless-steel pintle wire is inserted through all the loops to close the seam. In a spiral seam, coiled plastic spiral strips are attached to each end of the felt, the spirals from each end are meshed together, and a stainless-steel pintle wire is inserted through the interlocked spirals. Both types use a stainless-steel pintle wire as the closing element, and both can be opened for felt removal by withdrawing the wire. Pin seams are the most widely used. Spiral seams are preferred where very uniform seam geometry or higher lateral stability at the seam zone is required. |
Q3: Does the seam leave a mark on the paper surface? A correctly specified and manufactured seamed press felt leaves no mark on the paper surface. This requires that the seam zone matches the surrounding felt in three key respects: (1) the seam zone thickness must not differ significantly from the base felt caliper, so that the nip pressure does not spike or drop as the seam passes through; (2) the seam zone surface texture — including any batt coverage — must be consistent with the felt body surface; and (3) the permeability of the seam zone must be consistent with the felt body permeability, so there is no step change in drainage as the seam passes. PFM Screen designs the seam and seam-zone construction to meet all three criteria for the specified machine speed, NIP load, and paper grade. If the seam mark is a concern for your application, contact PFM Screen — we can provide reference data for the specific felt design at your operating conditions. |
Q4: How long does it take to install a seamed press felt compared to an endless felt? Installation time for a seamed press felt is typically 30–60 minutes once the old felt has been removed — the main steps are threading the flat felt through the press section and closing the seam by inserting the pintle wire. The entire felt change (including old felt removal) can often be completed in 1–2 hours with a crew of 2–3 people. An endless press felt typically requires 4–8 hours for the same operations, with a crew of 4–8 people and a full-width overhead crane lift that must be coordinated with adjacent area safety requirements. The reduction in downtime and manpower from seamed installation translates directly into production availability gain and lower maintenance cost per felt change. |
Q5: What paper machines and paper grades are seamed press felts suitable for? PFM Screen's seamed press felts are suitable for all paper machine types — fourdrinier machines, cylinder machines, multicylinder machines, gap formers, super-forming machines, and tissue machines — and all press positions from plain roll to vacuum suction and groove presses. They cover paper grades from ≥8 g/m² basis weight, including tissue and sanitary paper, writing and printing papers, newsprint, technical papers, kraft and packaging papers, corrugating medium, paper boards, and high-grade coated boards. The felt is suitable for both virgin and recycled fiber furnish. For shoe press positions (sustained NIP loads ≥200 kN/m), contact PFM Screen to confirm seam suitability for your specific press configuration. |
Q6: What base structures are available for seamed press felts, and how do I select the right one? PFM Screen's seamed press felts are available in single-layer, double-layer, and multi-layer base constructions — the same base structures as their endless felt equivalents. The base structure is selected based on the same criteria as for endless press felts: machine speed, NIP load, press type, paper grade, and target permeability. Single-layer base seamed felts are used for plain roll and nip roll presses at ≤80 kN/m; double-layer base seamed felts are used for vacuum suction, groove, and blind-hole presses at 60–200 kN/m; multi-layer base seamed felts are available for higher NIP positions. The seam type (pin or spiral) is then selected based on the base structure and press geometry. PFM Screen will recommend the correct combination based on your specifications. |
Q7: What are the technical specifications of PFM Screen's seamed press felts? PFM Screen's seamed press felts are manufactured to the following general specifications: GSM 800–1600 g/m² (depending on base structure — single-layer: 800–1200; double-layer: 950–1450; multi-layer: 1350–1600); base felt tensile strength ≥2500 N/5cm; elongation ≤0.8%; seam tensile strength ≥80% of base felt tensile; air permeability 25–120 CFM (adjusted per base structure and press type); maximum machine speed ≤1000 m/min. Available seam types: pin seam and spiral seam, both with stainless-steel pintle wire. These are indicative ranges — each felt is specified to the exact requirements of your press position and paper grade. Contact PFM Screen for a specific data sheet. |
Q8: What is the MOQ and lead time for seamed press felts from PFM Screen? There is no fixed minimum order quantity. PFM Screen accepts orders from a single seamed felt to bulk supply contracts. Standard lead time for custom-engineered seamed press felts is 2–4 weeks after specification confirmation and drawing approval. The pintle wire is supplied with the felt and can also be ordered separately for field replacement. To order, provide: machine make and model, press type and position, felt width (pin-to-pin), felt length, target paper grade, machine speed, NIP load, and preferred seam type (pin or spiral). If you are unsure about seam type or base structure, PFM Screen's technical team will recommend the optimal configuration based on your operating data. Contact via WhatsApp (+86 153 6967 9157) or email (polyestermesh@pfmscreen.com) for a quotation within 24 hours. |
Ready to Order? Get Your Custom Specification & Quote Within 24 Hours Tell us your machine type, press position, felt dimensions, NIP load, machine speed, paper grade, and preferred seam type — PFM Screen will issue a full specification and quotation within one business day. No fixed MOQ. WhatsApp: +86 153 6967 9157Email: polyestermesh@pfmscreen.com |
